Search results for: aircraft propulsion
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 591

Search results for: aircraft propulsion

171 Solar and Galactic Cosmic Ray Impacts on Ambient Dose Equivalent Considering a Flight Path Statistic Representative to World-Traffic

Authors: G. Hubert, S. Aubry

Abstract:

The earth is constantly bombarded by cosmic rays that can be of either galactic or solar origin. Thus, humans are exposed to high levels of galactic radiation due to altitude aircraft. The typical total ambient dose equivalent for a transatlantic flight is about 50 μSv during quiet solar activity. On the contrary, estimations differ by one order of magnitude for the contribution induced by certain solar particle events. Indeed, during Ground Level Enhancements (GLE) event, the Sun can emit particles of sufficient energy and intensity to raise radiation levels on Earth's surface. Analyses of GLE characteristics occurring since 1942 showed that for the worst of them, the dose level is of the order of 1 mSv and more. The largest of these events was observed on February 1956 for which the ambient dose equivalent rate is in the orders of 10 mSv/hr. The extra dose at aircraft altitudes for a flight during this event might have been about 20 mSv, i.e. comparable with the annual limit for aircrew. The most recent GLE, occurred on September 2017 resulting from an X-class solar flare, and it was measured on the surface of both the Earth and Mars using the Radiation Assessment Detector on the Mars Science Laboratory's Curiosity Rover. Recently, Hubert et al. proposed a GLE model included in a particle transport platform (named ATMORAD) describing the extensive air shower characteristics and allowing to assess the ambient dose equivalent. In this approach, the GCR is based on the Force-Field approximation model. The physical description of the Solar Cosmic Ray (i.e. SCR) considers the primary differential rigidity spectrum and the distribution of primary particles at the top of the atmosphere. ATMORAD allows to determine the spectral fluence rate of secondary particles induced by extensive showers, considering altitude range from ground to 45 km. Ambient dose equivalent can be determined using fluence-to-ambient dose equivalent conversion coefficients. The objective of this paper is to analyze the GCR and SCR impacts on ambient dose equivalent considering a high number statistic of world-flight paths. Flight trajectories are based on the Eurocontrol Demand Data Repository (DDR) and consider realistic flight plan with and without regulations or updated with Radar Data from CFMU (Central Flow Management Unit). The final paper will present exhaustive analyses implying solar impacts on ambient dose equivalent level and will propose detailed analyses considering route and airplane characteristics (departure, arrival, continent, airplane type etc.), and the phasing of the solar event. Preliminary results show an important impact of the flight path, particularly the latitude which drives the cutoff rigidity variations. Moreover, dose values vary drastically during GLE events, on the one hand with the route path (latitude, longitude altitude), on the other hand with the phasing of the solar event. Considering the GLE occurred on 23 February 1956, the average ambient dose equivalent evaluated for a flight Paris - New York is around 1.6 mSv, which is relevant to previous works This point highlights the importance of monitoring these solar events and of developing semi-empirical and particle transport method to obtain a reliable calculation of dose levels.

Keywords: cosmic ray, human dose, solar flare, aviation

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170 Performance of Constant Load Feed Machining for Robotic Drilling

Authors: Youji Miyake

Abstract:

In aircraft assembly, a large number of preparatory holes are required for screw and rivet joints. Currently, many holes are drilled manually because it is difficult to machine the holes using conventional computerized numerical control(CNC) machines. The application of industrial robots to drill the hole has been considered as an alternative to the CNC machines. However, the rigidity of robot arms is so low that vibration is likely to occur during drilling. In this study, it is proposed constant-load feed machining as a method to perform high-precision drilling while minimizing the thrust force, which is considered to be the cause of vibration. In this method, the drill feed is realized by a constant load applied onto the tool so that the thrust force is theoretically kept below the applied load. The performance of the proposed method was experimentally examined through the deep hole drilling of plastic and simultaneous drilling of metal/plastic stack plates. It was confirmed that the deep hole drilling and simultaneous drilling could be performed without generating vibration by controlling the tool feed rate in the appropriate range.

Keywords: constant load feed machining, robotic drilling, deep hole, simultaneous drilling

Procedia PDF Downloads 194
169 Generating Individualized Wildfire Risk Assessments Utilizing Multispectral Imagery and Geospatial Artificial Intelligence

Authors: Gus Calderon, Richard McCreight, Tammy Schwartz

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Forensic analysis of community wildfire destruction in California has shown that reducing or removing flammable vegetation in proximity to buildings and structures is one of the most important wildfire defenses available to homeowners. State laws specify the requirements for homeowners to create and maintain defensible space around all structures. Unfortunately, this decades-long effort had limited success due to noncompliance and minimal enforcement. As a result, vulnerable communities continue to experience escalating human and economic costs along the wildland-urban interface (WUI). Quantifying vegetative fuels at both the community and parcel scale requires detailed imaging from an aircraft with remote sensing technology to reduce uncertainty. FireWatch has been delivering high spatial resolution (5” ground sample distance) wildfire hazard maps annually to the community of Rancho Santa Fe, CA, since 2019. FireWatch uses a multispectral imaging system mounted onboard an aircraft to create georeferenced orthomosaics and spectral vegetation index maps. Using proprietary algorithms, the vegetation type, condition, and proximity to structures are determined for 1,851 properties in the community. Secondary data processing combines object-based classification of vegetative fuels, assisted by machine learning, to prioritize mitigation strategies within the community. The remote sensing data for the 10 sq. mi. community is divided into parcels and sent to all homeowners in the form of defensible space maps and reports. Follow-up aerial surveys are performed annually using repeat station imaging of fixed GPS locations to address changes in defensible space, vegetation fuel cover, and condition over time. These maps and reports have increased wildfire awareness and mitigation efforts from 40% to over 85% among homeowners in Rancho Santa Fe. To assist homeowners fighting increasing insurance premiums and non-renewals, FireWatch has partnered with Black Swan Analytics, LLC, to leverage the multispectral imagery and increase homeowners’ understanding of wildfire risk drivers. For this study, a subsample of 100 parcels was selected to gain a comprehensive understanding of wildfire risk and the elements which can be mitigated. Geospatial data from FireWatch’s defensible space maps was combined with Black Swan’s patented approach using 39 other risk characteristics into a 4score Report. The 4score Report helps property owners understand risk sources and potential mitigation opportunities by assessing four categories of risk: Fuel sources, ignition sources, susceptibility to loss, and hazards to fire protection efforts (FISH). This study has shown that susceptibility to loss is the category residents and property owners must focus their efforts. The 4score Report also provides a tool to measure the impact of homeowner actions on risk levels over time. Resiliency is the only solution to breaking the cycle of community wildfire destruction and it starts with high-quality data and education.

Keywords: defensible space, geospatial data, multispectral imaging, Rancho Santa Fe, susceptibility to loss, wildfire risk.

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168 A New Computational Tool for Noise Prediction of Rotating Surfaces (FACT)

Authors: Ana Vieira, Fernando Lau, João Pedro Mortágua, Luís Cruz, Rui Santos

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The air transport impact on environment is more than ever a limitative obstacle to the aeronautical industry continuous growth. Over the last decades, considerable effort has been carried out in order to obtain quieter aircraft solutions, whether by changing the original design or investigating more silent maneuvers. The noise propagated by rotating surfaces is one of the most important sources of annoyance, being present in most aerial vehicles. Bearing this is mind, CEIIA developed a new computational chain for noise prediction with in-house software tools to obtain solutions in relatively short time without using excessive computer resources. This work is based on the new acoustic tool, which aims to predict the rotor noise generated during steady and maneuvering flight, making use of the flexibility of the C language and the advantages of GPU programming in terms of velocity. The acoustic tool is based in the Formulation 1A of Farassat, capable of predicting two important types of noise: the loading and thickness noise. The present work describes the most important features of the acoustic tool, presenting its most relevant results and framework analyses for helicopters and UAV quadrotors.

Keywords: rotor noise, acoustic tool, GPU Programming, UAV noise

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167 Load Bearing Capacity and Operational Effectiveness of Single Shear Joints of CFRP Composite Laminate with Spread Tow Thin Plies

Authors: Tabrej Khan, Tamer A. Sebaey, Balbir Singh, M. A. Umarfarooq

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Spread-tow thin-ply-based technology has resulted in the progress of optimized reinforced composite plies with ultra-low thicknesses. There is wide use of composite bolted joints in the aircraft industry for load-bearing structures, and they are regarded as the primary source of stress concentration. The purpose of this study is to look into the bearing strength and structural performance of single shear bolt joint configurations in composite laminates, which are basically a combination of conventional thin-plies and thick-plies in some specific stacking sequence. The placement effect of thin-ply within the configured stack on bearing strength, as well as the potential damages, were investigated. Mechanical tests were used to understand the disfigurement mechanisms of the plies and their reciprocity, as well as to reflect on the single shear bolt joint properties and its load-bearing capacity. The results showed that changing the configuration of laminates by inserting the thin plies inside improved the bearing strength by up to 19%.

Keywords: hybrid composites, delamination, stress concentrations, mechanical testing, single bolt joint, thin-plies

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166 Selecting a Material for an Aircraft Diesel Engine Block

Authors: Ksenia Siadkowska, Tytus Tulwin, Rafał Sochaczewski

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Selecting appropriate materials is presently a complex task as material databases cover tens of thousands of different types of materials. Product designing proceeds in numerous stages and in most of them there are open questions with not only one correct solution but better and worse ones. This paper overviews the Diesel engine body construction materials mentioned in the literature and discusses a certain practical method to select materials for a cylinder head and a Diesel engine block as a prototype. The engine body, depending on its purpose, is most frequently iron or aluminum. If it is important to optimize parts to achieve low weight, aluminum alloys are usually applied, especially in the automotive and aviation industries. In the latter case, weight is even more important so new types of magnesium alloys which are even lighter than aluminum ones are developed and used. However, magnesium alloys are, for example, more flammable and not enough strong so, for safety reasons, this type of material is not used solely in engine bodies. Acknowledgement: This work has been realized in the cooperation with The Construction Office of WSK "PZL-KALISZ" S.A." and is part of Grant Agreement No. POIR.01.02.00-00-0002/15 financed by the Polish National Centre for Research and Development.

Keywords: aluminum alloy, cylinder head, Diesel engine, materials selection

Procedia PDF Downloads 395
165 Elite Child Athletes Are Our Future: Cardiac Adaptation to Monofin Training in Prepubertal Egyptian Athletes

Authors: Magdy Abouzeid, Nancy Abouzeid, Afaf Salem

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Background: The elite child athletes are one who has superior athletic talent. Monofin (a single surface swim fin) swimming already proved to be the most efficient method of swimming for human being. This is a novel descriptive study examining myocardial function indices in prepubertal monofin children. The aim of the present study was to determine the influence of long-term monofin training (LTMT), 36 weeks, 6 times per week, 90 min per unit on Myocardial function adaptation in elite child monofin athletes. Methods: 14 elite monofin children aged 11.95 years (± 1.09 yr) took part for (LTMT). All subjects underwent two-dimension, M-mode, and Doppler echocardiography before and after training to evaluate cardiac dimensions and function; septal and posterior wall thickness. Statistical methods of SPSS, means ± SD and paired t test, % of improvement were used. Findings: There was significant difference (p<0.01) and % improvement for all echocardiography parameter after (LTMT). Inter ventricular septal thickness in diastole and in systole increased by 27.9 % and 42.75 %. Left ventricular end systolic dimension and diastole increased by 16.81 % and 42.7 % respectively. Posterior wall thickness in systole very highly increased by 283.3 % and in diastole increased by 51.78 %. Left ventricular mass in diastole and in systole increased by 44.8 % and 40.1 % respectively. Stroke volume (SV) and resting heart rate (HR) significant changed (sv) 25 %, (HR) 14.7 %. Interpretation: the unique swim fin tool and create propulsion and overcome resistance. Further researches are needed to determine the effects of monofin training on right ventricular in child athletes.

Keywords: prepubertal, monofin training, heart athlete's, elite child athlete, echocardiography

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164 Numerical Investigations on the Coanda Effect

Authors: Florin Frunzulica, Alexandru Dumitrache, Octavian Preotu

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The Coanda effect consists of the tendency of a jet to remain attached to a sufficiently long/large convex surface. Flows deflected by a curved surface have caused great interest during last fifty years a major interest in the study of this phenomenon is caused by the possibility of using this effect to aircraft with short take-off and landing, for thrust vectoring. It is also used in applications involving mixing two of more fluids, noise attenuation, ventilation, etc. The paper proposes the numerical study of an aerodynamic configuration that can passively amplify the Coanda effect. On a wing flaps with predetermined configuration, a channel is applied between two particular zones, a low-pressure one and a high-pressure another one, respectively. The secondary flow through this channel yields a gap between the jet and the convex surface, maintaining the jet attached on a longer distance. The section altering-based active control of the secondary flow through the channel controls the attachment of the jet to the surface and automatically controls the deviation angle of the jet. The numerical simulations have been performed in Ansys Fluent for a series of wing flaps-channel configurations with varying jet velocity. The numerical results are in good agreement with experimental results.

Keywords: blowing jet, CFD, Coanda effect, circulation control

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163 Integrated Gas Turbine Performance Diagnostics and Condition Monitoring Using Adaptive GPA

Authors: Yi-Guang Li, Suresh Sampath

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Gas turbine performance degrades over time, and the degradation is greatly affected by environmental, ambient, and operating conditions. The engines may degrade slowly under favorable conditions and result in a waste of engine life if a scheduled maintenance scheme is followed. They may also degrade fast and fail before a scheduled overhaul if the conditions are unfavorable, resulting in serious secondary damage, loss of engine availability, and increased maintenance costs. To overcome these problems, gas turbine owners are gradually moving from scheduled maintenance to condition-based maintenance, where condition monitoring is one of the key supporting technologies. This paper presents an integrated adaptive GPA diagnostics and performance monitoring system developed at Cranfield University for gas turbine gas path condition monitoring. It has the capability to predict the performance degradation of major gas path components of gas turbine engines, such as compressors, combustors, and turbines, using gas path measurement data. It is also able to predict engine key performance parameters for condition monitoring, such as turbine entry temperature that cannot be directly measured. The developed technology has been implemented into digital twin computer Software, Pythia, to support the condition monitoring of gas turbine engines. The capabilities of the integrated GPA condition monitoring system are demonstrated in three test cases using a model gas turbine engine similar to the GE aero-derivative LM2500 engine widely used in power generation and marine propulsion. It shows that when the compressor of the model engine degrades, the Adaptive GPA is able to predict the degradation and the changing engine performance accurately using gas path measurements. Such a presented technology and software are generic, can be applied to different types of gas turbine engines, and provide crucial engine health and performance parameters to support condition monitoring and condition-based maintenance.

Keywords: gas turbine, adaptive GPA, performance, diagnostics, condition monitoring

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162 Determinants of Service Quality on Thai Passengers’ Repeated Purchase of Domestic Flight Service with Thai Airways International

Authors: Nattapong Techarattanased

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This research paper aimed to identify determinants of airline service quality on passengers’ repeated purchase of service. The population of this study was Thai passengers flying domestic flights with Thai Airways, making a total of 300 samples. These 300 samples participated in this research by answering a collection of questions by means of a questionnaire. An analysis of means score and multiple regression revealed that perceived service quality for tangible elements, reliability, responsiveness, assurance and empathy had determined repeated purchase of flight service of the passengers at a high level. Moreover, reliability and responsiveness factors could predict the passengers’ repeated purchase of flight service at the percentage of 30.6. The findings gave a signal that Thai Airways may consider a development of route network and fleet strategy as well as an establishment of aircraft and seat qualification to meet passengers’ needs and requirements. Passengers’ level of satisfaction could also be maximized by offering service value through various kinds of special deals and programs, whereas value- added pricing strategy should be considered in order to differentiate from and beat other leading airline competitors.

Keywords: repeated purchase, service quality, domestic flight, Thai Airways

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161 Tactical Urbanism and Sustainability: Tactical Experiences in the Promotion of Active Transportation

Authors: Aline Fernandes Barata, Adriana Sansão Fontes

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The overvaluation of the use of automobile has detrimentally affected the importance of pedestrians within the city and consequently its public spaces. As a way of treating contemporary urban paradigms, Tactical Urbanism aims to recover and activate spaces through fast and easily-applied actions that demonstrate the possibility of large-scale and long-term changes in cities. Tactical interventions have represented an important practice of redefining public spaces and urban mobility. The concept of Active Transportation coheres with the idea of sustainable urban mobility, characterizing the means of transportation through human propulsion, such as walking and cycling. This paper aims to debate the potential of Tactical Urbanism in promoting Active Transportation by revealing opportunities of transformation in the urban space of contemporary cities through initiatives that promote the protection and valorization of the presence of pedestrians and cyclists in cities, and that subvert the importance of motorized vehicles. In this paper, we present the character of these actions in two different ways: when they are used as tests for permanent interventions and when they have pre-defined start and end periods. Using recent initiatives to illustrate, we aim to discuss the role of small-scale actions in promoting and incentivizing a more active, healthy, sustainable and responsive urban way of life, presenting how some of them have developed through public policies. For that, we will present some examples of tactical actions that illustrate the encouragement of Active Transportation and trials to balance the urban opportunities for pedestrians and cyclists. These include temporary closure of streets, the creation of new alternatives and more comfortable areas for walking and cycling, and the subversion of uses in public spaces where the usage of cars are predominant.

Keywords: tactical urbanism, active transportation, sustainable mobility, non-motorized means

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160 An Experimental Study on the Temperature Reduction of Exhaust Gas at a Snorkeling of Submarine

Authors: Seok-Tae Yoon, Jae-Yeong Choi, Gyu-Mok Jeon, Yong-Jin Cho, Jong-Chun Park

Abstract:

Conventional submarines obtain propulsive force by using an electric propulsion system consisting of a diesel generator, battery, motor, and propeller. In the underwater, the submarine uses the electric power stored in the battery. After that, when a certain amount of electric power is consumed, the submarine floats near the sea water surface and recharges the electric power by using the diesel generator. The voyage carried out while charging the power is called a snorkel, and the high-temperature exhaust gas from the diesel generator forms a heat distribution on the sea water surface. The heat distribution is detected by weapon system equipped with thermo-detector and that is the main cause of reducing the survivability of the submarine. In this paper, an experimental study was carried out to establish optimal operating conditions of a submarine for reduction of infrared signature radiated from the sea water surface. For this, a hot gas generating system and a round acrylic water tank with adjustable water level were made. The control variables of the experiment were set as the mass flow rate, the temperature difference between the water and the hot gas in the water tank, and the water level difference between the air outlet and the water surface. The experimental instrumentation used a thermocouple of T-type to measure the released air temperature on the surface of the water, and a thermography system to measure the thermal energy distribution on the water surface. As a result of the experiment study, we analyzed the correlation between the final released temperature of the exhaust pipe exit in a submarine and the depth of the snorkel, and presented reasonable operating conditions for the infrared signature reduction of submarine.

Keywords: experiment study, flow rate, infrared signature, snorkeling, thermography

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159 Design and Fabrication of Pulse Detonation Engine Based on Numerical Simulation

Authors: Vishal Shetty, Pranjal Khasnis, Saptarshi Mandal

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This work explores the design and fabrication of a fundamental pulse detonation engine (PDE) prototype on the basis of pressure and temperature pulse obtained from numerical simulation of the same. PDE is an advanced propulsion system that utilizes detonation waves for thrust generation. PDEs use a fuel-air mixture ignited to create a supersonic detonation wave, resulting in rapid energy release, high pressures, and high temperatures. The operational cycle includes fuel injection, ignition, detonation, exhaust of combustion products, and purging of the chamber for the next cycle. This work presents details of the core operating principles of a PDE, highlighting its potential advantages over traditional jet engines that rely on continuous combustion. The design focuses on a straightforward, valve-controlled system for fuel and oxidizer injection into a detonation tube. The detonation was initiated using an electronically controlled spark plug or similar high-energy ignition source. Following the detonation, a purge valve was employed to expel the combusted gases and prepare the tube for the next cycle. Key considerations for the design include material selection for the detonation tube to withstand the high temperatures and pressures generated during detonation. Fabrication techniques prioritized readily available machining methods to create a functional prototype. This work detailed the testing procedures for verifying the functionality of the PDE prototype. Emphasis was given to the measurement of thrust generation and capturing of pressure data within the detonation tube. The numerical analysis presents performance evaluation and potential areas for future design optimization.

Keywords: pulse detonation engine, ignition, detonation, combustion

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158 Computational Fluid Dynamics Model of Various Types of Rocket Engine Nozzles

Authors: Konrad Pietrykowski, Michal Bialy, Pawel Karpinski, Radoslaw Maczka

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The nozzle is an element of the rocket engine in which the conversion of the potential energy of gases generated during combustion into the kinetic energy of the gas stream takes place. The design parameters of the nozzle have a decisive influence on the ballistic characteristics of the engine. Designing a nozzle assembly is, therefore, one of the most responsible stages in developing a rocket engine design. The paper presents the results of the simulation of three types of rocket propulsion nozzles. Calculations were made using CFD (Computational Fluid Dynamics) in ANSYS Fluent software. The next types of nozzles differ in shape. The analysis was made of a conical nozzle, a bell type nozzle with a conical supersonic part and a bell type nozzle. Calculation results are presented in the form of pressure, velocity and kinetic energy distributions of turbulence in the longitudinal section. The courses of these values along the nozzles are also presented. The results show that the cone nozzle generates strong turbulence in the critical section. Which negatively affect the flow of the working medium. In the case of a bell nozzle, the transformation of the wall caused the elimination of flow disturbances in the critical section. This reduces the probability of waves forming before or after the trailing edge. The most sophisticated construction is the bell type nozzle. It allows you to maximize performance without adding extra weight. The bell type nozzle can be used as a starter and auxiliary engine nozzle due to its advantages. The project/research was financed in the framework of the project Lublin University of Technology-Regional Excellence Initiative, funded by the Polish Ministry of Science and Higher Education (contract no. 030/RID/2018/19).

Keywords: computational fluid dynamics, nozzle, rocket engine, supersonic flow

Procedia PDF Downloads 158
157 Evaluation of Possible Application of Cold Energy in Liquefied Natural Gas Complexes

Authors: А. I. Dovgyalo, S. O. Nekrasova, D. V. Sarmin, A. A. Shimanov, D. A. Uglanov

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Usually liquefied natural gas (LNG) gasification is performed due to atmospheric heat. In order to produce a liquefied gas a sufficient amount of energy is to be consumed (about 1 kW∙h for 1 kg of LNG). This study offers a number of solutions, allowing using a cold energy of LNG. In this paper it is evaluated the application turbines installed behind the evaporator in LNG complex due to its work additional energy can be obtained and then converted into electricity. At the LNG consumption of G=1000kg/h the expansion work capacity of about 10 kW can be reached. Herewith-open Rankine cycle is realized, where a low capacity cryo-pump (about 500W) performs its normal function, providing the cycle pressure. Additionally discussed an application of Stirling engine within the LNG complex also gives a possibility to realize cold energy. Considering the fact, that efficiency coefficient of Stirling engine reaches 50 %, LNG consumption of G=1000 kg/h may result in getting a capacity of about 142 kW of such a thermal machine. The capacity of the pump, required to compensate pressure losses when LNG passes through the hydraulic channel, will make 500 W. Apart from the above-mentioned converters, it can be proposed to use thermoelectric generating packages (TGP), which are widely used now. At present, the modern thermoelectric generator line provides availability of electric capacity with coefficient of efficiency up to 15%. In the proposed complex, it is suggested to install the thermoelectric generator on the evaporator surface is such a way, that the cold end is contacted with the evaporator’s surface, and the hot one – with the atmosphere. At the LNG consumption of G=1000 kgг/h and specified coefficient of efficiency the capacity of the heat flow Qh will make about 32 kW. The derivable net electric power will be P=4,2 kW, and the number of packages will amount to about 104 pieces. The carried out calculations demonstrate the research perceptiveness in this field of propulsion plant development, as well as allow realizing the energy saving potential with the use of liquefied natural gas and other cryogenics technologies.

Keywords: cold energy, gasification, liquefied natural gas, electricity

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156 Comparison Analysis on the Safety Culture between the Executives and the Operators: Case Study in the Aircraft Manufacturer in Taiwan

Authors: Wen-Chen Hwang, Yu-Hsi Yuan

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According to the estimation made by researchers of safety and hygiene, 80% to 90% of workplace accidents in enterprises could be attributed to human factors. Nevertheless, human factors are not the only cause for accidents; instead, happening of accidents is also closely associated with the safety culture of the organization. Therefore, the most effective way of reducing accident rate would be to improve the social and the organizational factors that influence organization’s safety performance. Overview the present study is to understand the current level of safety culture in manufacturing enterprises. A tool for evaluating safety culture matching the needs and characteristics of manufacturing enterprises was developed by reviewing literature of safety culture, and taking the special backgrounds of the case enterprises into consideration. Expert validity was also implied for developing the questionnaire. Moreover, safety culture assessment was conducted through the practical investigation of the case enterprises. Total 505 samples were involved, 53 were executives and 452 were operators. The result of this study in comparison of the safety culture level between the executives and the operators was reached the significant level in 8 dimensions: Safety Commitment, Safety System, Safety Training, Safety Involvement, Reward and Motivation, Communication and Reporting, Leadership and Supervision, Learning and Changing. In general, the overall safety culture were executive level higher than operators level (M: 74.98 > 69.08; t=2.87; p < 0.01).

Keywords: questionnaire survey, safety culture, t-test, media studies

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155 A Fuzzy TOPSIS Based Model for Safety Risk Assessment of Operational Flight Data

Authors: N. Borjalilu, P. Rabiei, A. Enjoo

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Flight Data Monitoring (FDM) program assists an operator in aviation industries to identify, quantify, assess and address operational safety risks, in order to improve safety of flight operations. FDM is a powerful tool for an aircraft operator integrated into the operator’s Safety Management System (SMS), allowing to detect, confirm, and assess safety issues and to check the effectiveness of corrective actions, associated with human errors. This article proposes a model for safety risk assessment level of flight data in a different aspect of event focus based on fuzzy set values. It permits to evaluate the operational safety level from the point of view of flight activities. The main advantages of this method are proposed qualitative safety analysis of flight data. This research applies the opinions of the aviation experts through a number of questionnaires Related to flight data in four categories of occurrence that can take place during an accident or an incident such as: Runway Excursions (RE), Controlled Flight Into Terrain (CFIT), Mid-Air Collision (MAC), Loss of Control in Flight (LOC-I). By weighting each one (by F-TOPSIS) and applying it to the number of risks of the event, the safety risk of each related events can be obtained.

Keywords: F-topsis, fuzzy set, flight data monitoring (FDM), flight safety

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154 The 5G Communication Technology Radiation Impact on Human Health and Airports Safety

Authors: Ashraf Aly

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The aim of this study is to examine the impact of 5G communication technology radiation on human health and airport safety. The term 5G refers to the fifth generation of wireless mobile technology. The 5G wireless technology will increase the number of high-frequency-powered base stations and other devices and browsing and download speeds, as well as improve the network connectivity and play a big part in improving the performance of integrated applications, such as self-driving cars, medical devices, and robotics. 4G was the latest embedded version of mobile networking technology called 4G, and 5G is the new version of wireless technology. 5G networks have more features than 4G networks, such as lower latency, higher capacity, and increased bandwidth compared to 4G. 5G network improvements over 4G will have big impacts on how people live, business, and work all over the world. But neither 4G nor 5G have been tested for safety and show harmful effects from this wireless radiation. This paper presents biological factors on the effects of 5G radiation on human health. 5G services use C-band radio frequencies; these frequencies are close to those used by radio altimeters, which represent important equipment for airport and aircraft safety. The aviation industry, telecommunications companies, and their regulators have been discussing and weighing these interference concerns for years.

Keywords: wireless communication, radiofrequency, Electromagnetic field, environmental issues

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153 Minimizing Ship’S Breakdown Maintenance Due to Rope Entangled In Propeller With “Si Kuman” On Mooring Boat PSC I in Surabaya

Authors: Jogi Prayogo, Dwi Qaqa Prasetyatama, Rahmad Dwi Afandi, Kunto Arief Prasetyo, Viorel Herniza Leksono

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PT. Pertamina Trans Kontinental managed a fleet of 364 ships in 2018 - 2020. In that period, there were 8 incidents of ship damage, causing breakdown maintenance on 6 ships belonging to PT Pertamina Trans Kontinental throughout Indonesia's operational areas due to ropes entangled in propellers. The company's losses that were caused by the fouled propellers amounted to 306.35 Million Rupiah. Of the 8 incidents, Mooring Boat PSC I was taken as a pilot project for further analysis considering the location of the ship which is in Surabaya and Mooring Boat PSC I has experienced 2 incidents of rope entanglement that caused the company's losses due to the largest Breakdown Maintenance amounted to 200.99 Million Rupiah. After analyzing the rope entanglement in the ship's propeller based on the data of Mooring Boat PSC I related to the location of propellers that are often fouled in the conventional propulsion system, it was found that there is a suitable location for the implementation of SI KUMAN tool that serves to cut ropes to prevent the occurrence of rope entangled in ship propellers. The determination of SI KUMAN tool is based on the strength of the ship's material to be installed and a suitable design to prevent the occurrence of ropes being entangled in propellers. After the installation of the "SI KUMAN" tool and monitoring carried out for 1 year period (August 2020 - August 2021), it was found that SI KUMAN tool can eliminate the risk of fouled propeller incidents which previously occurred twice in one year so that the company's loss amounted to 200.99 Million Rupiah can be eliminated and SI KUMAN tool can still operate optimally.

Keywords: breakdown maintenance, mooring boat, fleet, fouled propeller, rope entangled, cut

Procedia PDF Downloads 181
152 Energy Efficient Autonomous Lower Limb Exoskeleton for Human Motion Enhancement

Authors: Nazim Mir-Nasiri, Hudyjaya Siswoyo Jo

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The paper describes conceptual design, control strategies, and partial simulation for a new fully autonomous lower limb wearable exoskeleton system for human motion enhancement that can support its weight and increase strength and endurance. Various problems still remain to be solved where the most important is the creation of a power and cost efficient system that will allow an exoskeleton to operate for extended period without batteries being frequently recharged. The designed exoskeleton is enabling to decouple the weight/mass carrying function of the system from the forward motion function which reduces the power and size of propulsion motors and thus the overall weight, cost of the system. The decoupling takes place by blocking the motion at knee joint by placing passive air cylinder across the joint. The cylinder is actuated when the knee angle has reached the minimum allowed value to bend. The value of the minimum bending angle depends on usual walk style of the subject. The mechanism of the exoskeleton features a seat to rest the subject’s body weight at the moment of blocking the knee joint motion. The mechanical structure of each leg has six degrees of freedom: four at the hip, one at the knee, and one at the ankle. Exoskeleton legs are attached to subject legs by using flexible cuffs. The operation of all actuators depends on the amount of pressure felt by the feet pressure sensors and knee angle sensor. The sensor readings depend on actual posture of the subject and can be classified in three distinct cases: subject stands on one leg, subject stands still on both legs and subject stands on both legs but transit its weight from one leg to other. This exoskeleton is power efficient because electrical motors are smaller in size and did not participate in supporting the weight like in all other existing exoskeleton designs.

Keywords: energy efficient system, exoskeleton, motion enhancement, robotics

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151 Development of Transparent Nano-Structured Super-Hydrophobic Coating on Glass and Evaluation of Anti-Dust Properties

Authors: Abhilasha Mishra, Neha Bhatt

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Super-hydrophobicity is an effect in which a surface roughness and chemical composition are combined to produce unusual water and dust repellent surface. The super-hydrophobic surface is widely used in many applications such as windshields of the automobile, aircraft, lens, solar cells, roofing, boat hull, paints, etc. Four coating solutions were prepared by varying compositions of 1,1,1,3,3,3 hexametyldisilazane (HDMS) and tetraethylorthosilicate (TEOS) sol. These solutions were coated on glass slides by a spin coating method and etched at a high temperature ranging 250 -350 oC. All the coatings were studied for its different properties like water repellent, anti-dust, and transparency and contact angle measurements. Stability of coatings was also studied with respect to temperature, external environment, and pH. It was found that all coatings impart a significant super-hydrophobicity on a glass surface with contact angle ranging from 156o to 162o and have good stability in the external environment. The results of the different coatings were observed and compared with each other. On increasing layers of coatings the super-hydrophobicity and anti-dust properties increases but after 3 coatings the transparency of coating starts decreasing.

Keywords: super-hydrophobic, contact angle, coating, anti-dust

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150 A Robust and Adaptive Unscented Kalman Filter for the Air Fine Alignment of the Strapdown Inertial Navigation System/GPS

Authors: Jian Shi, Baoguo Yu, Haonan Jia, Meng Liu, Ping Huang

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Adapting to the flexibility of war, a large number of guided weapons launch from aircraft. Therefore, the inertial navigation system loaded in the weapon needs to undergo an alignment process in the air. This article proposes the following methods to the problem of inaccurate modeling of the system under large misalignment angles, the accuracy reduction of filtering caused by outliers, and the noise changes in GPS signals: first, considering the large misalignment errors of Strapdown Inertial Navigation System (SINS)/GPS, a more accurate model is made rather than to make a small-angle approximation, and the Unscented Kalman Filter (UKF) algorithms are used to estimate the state; then, taking into account the impact of GPS noise changes on the fine alignment algorithm, the innovation adaptive filtering algorithm is introduced to estimate the GPS’s noise in real-time; at the same time, in order to improve the anti-interference ability of the air fine alignment algorithm, a robust filtering algorithm based on outlier detection is combined with the air fine alignment algorithm to improve the robustness of the algorithm. The algorithm can improve the alignment accuracy and robustness under interference conditions, which is verified by simulation.

Keywords: air alignment, fine alignment, inertial navigation system, integrated navigation system, UKF

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149 Simulation and Experimental Research on Pocketing Operation for Toolpath Optimization in CNC Milling

Authors: Rakesh Prajapati, Purvik Patel, Avadhoot Rajurkar

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Nowadays, manufacturing industries augment their production lines with modern machining centers backed by CAM software. Several attempts are being made to cut down the programming time for machining complex geometries. Special programs/software have been developed to generate the digital numerical data and to prepare NC programs by using suitable post-processors for different machines. By selecting the tools and manufacturing process then applying tool paths and NC program are generated. More and more complex mechanical parts that earlier were being cast and assembled/manufactured by other processes are now being machined. Majority of these parts require lots of pocketing operations and find their applications in die and mold, turbo machinery, aircraft, nuclear, defense etc. Pocketing operations involve removal of large quantity of material from the metal surface. The modeling of warm cast and clamping a piece of food processing parts which the used of Pro-E and MasterCAM® software. Pocketing operation has been specifically chosen for toolpath optimization. Then after apply Pocketing toolpath, Multi Tool Selection and Reduce Air Time give the results of software simulation time and experimental machining time.

Keywords: toolpath, part program, optimization, pocket

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148 Impact of COVID-19 Pandemic in the European Air Transport Command during 2020-2021

Authors: Martin Gascón Hove, Ralph Vermeltfoort, Alessandro Fiorini, Erwan Dulaurent, Henning von Perbandt

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Introduction: The outbreak of the COVID-19 pandemic has completely changed the global health situation, with more than 400 million cases published and over 5 million deaths. European Air Transport Command (EATC) is integrated by seven nations, and among its capabilities is that of aeromedical evacuation (AM). Material and methods: Impact of novel coronavirus was analysed based on the number and characteristics of patients and executed missions within EATC and, particularly by Spain, during the biennium 2020-2021. Results: One thousand sixty patients were transported in 186 missions. Neither death nor disease contagion was reported during AM performances. Military cases transferred were 986, mostly routine priority (91,4%), and 74 were civilians, who were transported in 17 missions, and 81,1% of which were categorized as urgent. Niger led the list of original countries, with 191 evacuated patients. 76,1% of requests came from Italy and Germany. Airbus A310 was the most used aircraft (32,2%). Germany transported 222 patients of another nationality, while Spain executed eight missions and repatriated 68 cases, 58 of which were from Mali. Conclusions: COVID-19 has led to a surged number of evacuated patients inside EATC, which has proven to be a safe and effective means of transportation, even in critical cases. Spain has gained prominence since its annexation in 2015.

Keywords: COVID-19, SARS-CoV-2, pandemic, aviation, Spain

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147 Examining the Challenges Faced by Passengers Using Arik Air for International and Domestic Travel

Authors: Mahmud Hafsat Hussaini, Eldah Ephraim Eldah, Bata Zoakah Amina

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This research work was aimed at examining the challenges faced by passengers using Arik air for domestic and international travels. Passengers do complain of delay flights, theft and rude behavior by Arik staff while on transit or in the process of travelling using the aircraft. Being the national carrier in Nigeria these behaviors have tarnished the image of the airline and makes travel experience to be challenging. Hundred survey questionnaires were administered to travellers who have used the airline for domestic and international flights. Findings show that the staff of the airline do lack customer care skills and are sometimes rude to customers. The airline does have different agents that book for international flights who delays confirming bookings even after payment. The website of the airline is mostly down and makes bookings difficult. Other findings related to the study are a delay of domestic flights within Nigeria. Passengers are sometimes kept for 8 hours in the airport due to delay of flights. The study, therefore, recommends that flight schedule should be adhered to and staff should be trained to meet of with passengers demand. The security of guest luggage at the airport should be put in place to avoid theft. An effective booking platform should be accessible to passengers for easy booking.

Keywords: examining, challenges, domestic, international, travels

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146 Impact of Large Scale Solar Power Plant on Airports and Aviation

Authors: Munirah Stapah Salleh, Ahmad Rosly Abbas, Sazalina Zakaria, Nur Iffika Ruslan, Nurfaziera Rahim

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One of the areas that require a massive amount of energy is the airport. Hence, several airports have increased their reliance on renewable energy, specifically solar photovoltaic (PV) systems, to solve the issue. The interest regarding the installations of airport-based solar farms caught much attention. This, at the same time, helps to minimize the reliance on conventional energy sources that are fossil-based. However, many concerns were raised on the solar PV systems, especially on the effect of potential glare occurrence to the pilots during their flies. This paper will be discussing both the positive and negative impact of the large scale solar power plant on airports and aviation. Installing the large scale solar have negative impacts on airport and aviation, such as physical collision hazards, potential interference, or voltage problems with aircraft navigational and surveillance equipment as well as potential glare. On the positive side, it helps to lower environmental footprint, acquiring less energy from the utility provider, which are traditionally highly relying on other energy sources that have larger effects on the environment, and, last but not least, reduce the power supply uncertainty.

Keywords: solar photovoltaic systems, large scale solar, airport, glare effects

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145 Radio Regulation Development and Radio Spectrum Analysis of Earth Station in Motion Service

Authors: Fei Peng, Jun Yuan, Chen Fan, Fan Jiang, Qian Sun, Yudi Liu

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Although Earth Station in Motion (ESIM) services are widely used and there is a huge market demand around the world, International Telecommunication Union (ITU) does not have unified conclusion for the use of ESIM yet. ESIM are Mobile Satellite Services (MSS) due to its mobile-based attributes, while multiple administrations want to use ESIM in Fixed Satellite Service (FSS). However, Radio Regulations (RR) have strict distinction between MSS and FSS. In this case, ITU has been very controversial because this kind of application will violate the RR Article and the conflict will bring risks to the global deployment. Thus, this paper illustrates the development of rules, regulations, standards concerning ESIM and the radio spectrum usage of ESIM in different regions around the world. Firstly, the basic rules, standard and definition of ITU’s Radiocommunication Sector (ITU-R) is introduced. Secondly, the World Radiocommunication Conference (WRC) agenda item on radio spectrum allocation for ESIM, e.g. in C/Ku/Ka band, is introduced and multi-view on the radio spectrum allocation is elaborated, especially on 19.7-20.2 GHz & 29.5-30.0 GHz. Then, some ITU-R Recommendations and Reports are analyzed on the specific technique to enable these ESIM to communicate with Geostationary Earth Orbit Satellite (GSO) space stations in the FSS without causing interference at levels in excess of that caused by conventional FSS earth stations. Meanwhile, the opposite opinion on not allocating EISM service in FSS frequency band is also elaborated. Finally, based on the ESIM’s future application, the ITU-R standards development trend is forecasted. In conclusion, using radio spectrum resource in an equitable, rational and efficient manner is the basic guideline of ITU. Although it is not a good approach to obstruct the revise of RR when there is a large demand for radio spectrum resource in satellite industry, still the propulsion and global demand of the whole industry may face difficulties on the unclear application in modify rules of RR.

Keywords: earth station in motion, ITU standards, radio regulations, radio spectrum, satellite communication

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144 Lamb Waves Propagation in Elastic-Viscoelastic Three-Layer Adhesive Joints

Authors: Pezhman Taghipour Birgani, Mehdi Shekarzadeh

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In this paper, the propagation of lamb waves in three-layer joints is investigated using global matrix method. Theoretical boundary value problem in three-layer adhesive joints with perfect bond and traction free boundary conditions on their outer surfaces is solved to find a combination of frequencies and modes with the lowest attenuation. The characteristic equation is derived by applying continuity and boundary conditions in three-layer joints using global matrix method. Attenuation and phase velocity dispersion curves are obtained with numerical solution of this equation by a computer code for a three-layer joint, including an aluminum repair patch bonded to the aircraft aluminum skin by a layer of viscoelastic epoxy adhesive. To validate the numerical solution results of the characteristic equation, wave structure curves are plotted for a special mode in two different frequencies in the adhesive joint. The purpose of present paper is to find a combination of frequencies and modes with minimum attenuation in high and low frequencies. These frequencies and modes are recognizable by transducers in inspections with Lamb waves because of low attenuation level.

Keywords: three-layer adhesive joints, viscoelastic, lamb waves, global matrix method

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143 Methane Production from Biomedical Waste (Blood)

Authors: Fatima M. Kabbashi, Abdalla M. Abdalla, Hussam K. Hamad, Elias S. Hassan

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This study investigates the production of renewable energy (biogas) from biomedical hazard waste (blood) and eco-friendly disposal. Biogas is produced by the bacterial anaerobic digestion of biomaterial (blood). During digestion process bacterial feeding result in breaking down chemical bonds of the biomaterial and changing its features, by the end of the digestion (biogas production) the remains become manure as known. That has led to the economic and eco-friendly disposal of hazard biomedical waste (blood). The samples (Whole blood, Red blood cells 'RBCs', Blood platelet and Fresh Frozen Plasma ‘FFP’) are collected and measured in terms of carbon to nitrogen C/N ratio and total solid, then filled in connected flasks (three flasks) using water displacement method. The results of trails showed that the platelet and FFP failed to produce flammable gas, but via a gas analyzer, it showed the presence of the following gases: CO, HC, CO₂, and NOX. Otherwise, the blood and RBCs produced flammable gases: Methane-nitrous CH₃NO (99.45%), which has a blue color flame and carbon dioxide CO₂ (0.55%), which has red/yellow color flame. Methane-nitrous is sometimes used as fuel for rockets, some aircraft and racing cars.

Keywords: renewable energy, biogas, biomedical waste, blood, anaerobic digestion, eco-friendly disposal

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142 An Innovation and Development System for a New Hybrid Composite Technology in Aerospace Industry

Authors: M. Fette, J. P. Wulfsberg, A. Herrmann, R. H. Ladstaetter

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Present and future lightweight design represents an important key to successful implementation of energy-saving, fuel-efficient and environmentally friendly means of transport in the aerospace and automotive industry. In this context the use of carbon fibre reinforced plastics (CFRP) which are distinguished by their outstanding mechanical properties at relatively low weight, promise significant improvements. Due to the reduction of the total mass, with the resulting lowered fuel or energy consumption and CO2 emissions during the operational phase, commercial aircraft and future vehicles will increasingly be made of CFRP. An auspicious technology for the efficient and economic production of high performance thermoset composites and hybrid structures for future lightweight applications is the combination of carbon fibre sheet moulding compound (SMC), tailored continuous carbon fibre reinforcements and metallic components in a one-shot pressing and curing process. This paper deals with a new hybrid composite technology for aerospace industries, which was developed with the help of a universal innovation and development system. This system supports the management of idea generation, the methodical development of innovative technologies and the achievement of the industrial readiness of these technologies.

Keywords: development system, hybrid composite, innovation system, prepreg, sheet moulding compound

Procedia PDF Downloads 340