Search results for: heat flux measurement

Authors: Jay P. Sipani, Riki H. Patel, Trushit Upadhyaya

Abstract:

Today there is a demand to monitor environmental factors almost in all research institutes and industries and even for domestic uses. The analog data measurement requires manual effort to note readings, and there may be a possibility of human error. Such type of systems fails to provide and store precise values of parameters with high accuracy. Analog systems are having drawback of storage/memory. Therefore, there is a requirement of a smart system which is fully automated, accurate and capable enough to monitor all the environmental parameters with utmost possible accuracy. Besides, it should be cost-effective as well as portable too. This paper represents the Wireless Sensor (WS) data communication using DHT11, Arduino, SIM900A GSM module, a mobile device and Liquid Crystal Display (LCD). Experimental setup includes the heating arrangement of DHT11 and transmission of its data using Arduino and SIM900A GSM shield. The mobile device receives the data using Arduino, GSM shield and displays it on LCD too. Heating arrangement is used to heat and cool the temperature sensor to study its characteristics.

Keywords: wireless communication, Arduino, DHT11, LCD, SIM900A GSM module, mobile phone SMS

Procedia PDF Downloads 282

Authors: Jihane Saad, Thomas Lendormi, Caroline Le Marechal, Anne-marie Pourcher, Céline Druilhe, Jean-louis Lanoiselle

Abstract:

Agricultural anaerobic digestion consists in the conversion of animal slurry and manure into biogas and digestate. They need, however, to be treated at 70 ºC during 60 min before anaerobic digestion according to the European regulation (EC n°1069/2009 & EU n°142/2011). The impact of such heat treatment on the outcome of bacteria has been poorly studied up to now. Moreover, a recent study¹ has shown that enterococci and clostridia are still detected despite the application of such thermal treatment, questioning the relevance of this approach for the hygienisation of digestate. The aim of this study is to establish the heat inactivation kinetics of two species of enterococci (Enterococcus faecalis and Enterococcus faecium) and two species of clostridia (Clostridioides difficile and Clostridium novyi as a non-toxic model for Clostridium botulinum of group III). A pure culture of each strain was prepared in a specific sterile medium at concentration of 10⁴ – 10⁷ MPN / mL (Most Probable number), depending on the bacterial species. Bacterial suspensions were then filled in sterilized capillary tubes and placed in a water or oil bath at desired temperature for a specific period of time. Each bacterial suspension was enumerated using a MPN approach, and tests were repeated three times for each temperature/time couple. The inactivation kinetics of the four indicator bacteria is described using the Weibull model and the classical Bigelow model of first-order kinetics. The Weibull model takes biological variation, with respect to thermal inactivation, into account and is basically a statistical model of distribution of inactivation times as the classical first-order approach is a special case of the Weibull model. The heat treatment at 70 ºC / 60 min contributes to a reduction greater than 5 log10 for E. faecium and E. faecalis. However, it results only in a reduction of about 0.7 log10 for C. difficile and an increase of 0.5 log10 for C. novyi. Application of treatments at higher temperatures is required to reach a reduction greater or equal to 3 log10 for C. novyi (such as 30 min / 100 ºC, 13 min / 105 ºC, 3 min / 110 ºC, and 1 min / 115 ºC), raising the question of the relevance of the application of heat treatment at 70 ºC / 60 min for these spore-forming bacteria. To conclude, the heat treatment (70 ºC / 60 min) defined by the European regulation is sufficient to inactivate non-sporulating bacteria. Higher temperatures (> 100 ºC) are required as far as spore-forming bacteria concerns to reach a 3 log10 reduction (sporicidal activity).

Keywords: heat treatment, enterococci, clostridia, inactivation kinetics

Procedia PDF Downloads 113

Authors: Pranjal Johri, Misbah Ul-Islam

Abstract:

Power Transformers are one of the most critical and failure prone entities in an electrical power system. It is an established practice that each design of a power transformer has to undergo numerous type tests for design validation and routine tests are performed on each and every power transformer before dispatch from manufacturer’s works. Different countries follow different standards for testing the transformers. Most common and widely followed standard for Power Transformers is IEC 60076 series. Though these standards put up a strict testing requirements for power transformers, however, few aspects of transformer characteristics and guaranteed parameters can be ensured by some additional tests. Based on certain observations during routine test of a transformer and analyzing the data of a large fleet of transformers, three propositions have been discussed and put forward to be included in test schedules and standards. The observations in the routine test raised questions on design flux density of transformer. In order to ensure that flux density in any part of the core & yoke does not exceed 1.9 tesla at 1.1 pu as well, following propositions need to be followed during testing:  From the data studied, it was evident that generally NLC at 1.1 pu is apporx. 3 times of No Load Current at 1 pu voltage.  During testing the power factor at 1.1 pu excitation, it must be comparable to calculated values from the Cold Rolled Grain Oriented steel material curves, including building factor.  A limit of 3 % to be extended for higher than rated voltages on difference in Vavg and Vrms, during no load testing.  Extended over excitation test to be done in case above propositions are observed to be violated during testing.

Keywords: power transfoemrs, no load current, DGA, power factor

Procedia PDF Downloads 104

Authors: Vedansh More, Lalatendu Bal, Ronak Panchal, Atharva Kulkarni

Abstract:

The project aims at developing a cost-effective test bench capable of testing and validating the complete powertrain package of an electric vehicle. Emrax 228 high voltage synchronous motor was selected as the prime mover for study. A tandem type dynamometer comprising of two loading methods; inertial, using standard inertia rollers and absorptive, using a separately excited DC generator with resistive coils was developed. The absorptive loading of the prime mover was achieved by implementing a converter circuit through which duty of the input field voltage level was controlled. This control was efficacious in changing the magnetic flux and hence the generated voltage which was ultimately dropped across resistive coils assembled in a load bank with all parallel configuration. The prime mover and loading elements were connected via a chain drive with a 2:1 reduction ratio which allows flexibility in placement of components and a relaxed rating of the DC generator. The development will aid in determination of essential characteristics like torque-RPM, power-RPM, torque factor, RPM factor, heat loads of devices and battery pack state of charge efficiency but also provides a significant financial advantage over existing versions of dynamometers with its cost-effective solution.

Keywords: absorptive load, chain drive, chordal action, DC generator, dynamometer, electric vehicle, inertia rollers, load bank, powertrain, pulse width modulation, reduction ratio, road load, testbench

Procedia PDF Downloads 232

Authors: Tayyab Hassan, Talha Rehman, Qasim Abdul Aziz, Ahmad Salman

Abstract:

The constant monitoring of blood glucose level is necessary for maintaining health of patients and to alert medical specialists to take preemptive measures before the onset of any complication as a result of diabetes. The current clinical monitoring of blood glucose uses invasive methods repeatedly which are uncomfortable and may result in infections in diabetic patients. Several attempts have been made to develop non-invasive techniques for blood glucose measurement. In this regard, the existing methods are not reliable and are less accurate. Other approaches claiming high accuracy have not been tested on extended dataset, and thus, results are not statistically significant. It is a well-known fact that acetone concentration in breath has a direct relation with blood glucose level. In this paper, we have developed the first of its kind, reliable and high accuracy breath analyzer for non-invasive blood glucose measurement. The acetone concentration in breath was measured using MQ 138 sensor in the samples collected from local hospitals in Pakistan involving one hundred patients. The blood glucose levels of these patients are determined using conventional invasive clinical method. We propose a linear regression classifier that is trained to map breath acetone level to the collected blood glucose level achieving high accuracy.

Keywords: blood glucose level, breath acetone concentration, diabetes, linear regression

Procedia PDF Downloads 172

Authors: Yassine Jadi, Lin Jie

Abstract:

In order to serve the society in an electronic manner, many developing countries have launched tremendous e-government projects. The strategies of development and implementation e-government system have reached different levels, and to ensure consistency of development, the governments need to evaluate e-government performance. The United nation has design e-government development ranking index (EGDI) that rely on three indexes, Online service index (OSI), Telecommunication Infrastructure index (TII), and human capital index( HCI) which are not reflecting the interaction between a government and their citizens. Based on data envelopment analyses (DEA) technique, we are using E-participating index (EPI) as an output of government effort to evaluate the performance of e-government system. Therefore, the ranking index can be achieved in efficiency manner.

Keywords: e-government, DEA, efficiency measurement, EGDI

Procedia PDF Downloads 376

Authors: Chalermporn Jindapeng

Abstract:

The main objective of the study of the suitable operating conditions of hot water generators combined with central air package units: a case study of Tipco Building Group was to analyze the suitable operating conditions and energy-related costs in each operating condition of hot water generators combined with central air package units which resulted in water-cooled packages. Thermal energy from vapor form refrigerants at high pressures and temperatures was exchanged with thermal energy of the water in the swimming pool that required suitable temperature control for users with the use of plate heat exchangers before refrigerants could enter the condenser in its function to change the status of vapor form refrigerants at high pressures and temperatures to liquid form at high pressures and temperatures. Thus, if this was used to replace heat pumps it could reduce the electrical energy that was used to make hot water and reduce the cost of the electrical energy of air package units including the increased efficacy of air package units. Of the analyses of the suitable operating conditions by means of the study of the elements involved with actual measurements from the system that had been installed at the Tipco Building Group hot water generators were combined with air package units which resulted in water-cooled packages with a cooling capacity of 75 tonnes. Plate heat exchangers were used in the transfer of thermal energy from refrigerants to one set of water with a heat exchanger area of 1.5 m² which was used to increase the temperature of swimming pool water that has a capacity of 240 m³. From experimental results, it was discovered after continuous temperature measurements in the swimming pool every 15 minutes that swimming pool water temperature increased by 0.78 ⁰C 0.75 ⁰C 0.74 ⁰C and 0.71 ⁰C. The rates of flow of hot water through the heat exchangers were equal to 14, 16, 18 and 20 litres per minute respectively where the swimming pool water temperature was at a constant value and when the rate of flow of hot water increased this caused hot water temperatures to decrease and the coefficient of performance of the air package units to increase from 5.9 to 6.3, 6.7, 6.9 and 7.6 while the rates of flow of hot water were equal to 14, 16, 18 and 20 litres per minute, respectively. As for the cooling systems, there were no changes and the system cooling functions were normal as the cooling systems were able to continuously transfer incoming heat for the swimming pool water which resulted in a constant pressure in the cooling system that allowed its cooling functions to work normally.

Keywords: central air package units, heat exchange, hot water generators, swimming pool

Procedia PDF Downloads 258

Authors: Bahareh Najafian Ashrafi, Hossein Zeidabadinejad, Mehdi Ashjaee

Abstract:

The temperature field is a key factor of flame heat transfer rate and therefore should be measured accurately. In this study, the Mach-Zehnder Interferometry method is applied to measure the temperature field of premixed air/landfill gas (LFG60:60% CH4+40% CO2) laminar flame. The three-dimensional flame of cylindrical slot burner can assume to be two-dimensional due to the high aspect ratio (L/W=10) of the rectangular slot. So, the method converts two-dimensional flame to closed isothermal curves called fringes and the outer fringes temperature is measured by thermocouples. The experiments are carried out for Reynolds numbers and equivalence ratios ranging from 100 to 400 and 1.0 to 1.4, respectively. Results show that by increasing the equivalence ratio or Reynolds number, the flame height increases. The maximum flame temperature decreases by increasing the equivalence ratio but does not change considerably by changing the Reynolds number.

Keywords: landfill gas, Mach-Zehender interferometry, premix flame, slot burner, temperature filed

Procedia PDF Downloads 150

Authors: Caitlin Bailey, Marian Frattarola Saulino, Beth Steinberg

Abstract:

Today, virtually all programs offered to people with intellectual and developmental disabilities tout themselves as person-centered, community-based and inclusive, yet there is a vast range in type and quality of services that use these similar descriptors. The issue is exacerbated by the fields’ measurement practices around quality, inclusion, independent living, choice and person-centered outcomes. For instance, community inclusion for people with disabilities is often measured by the number of times person steps into his or her community. These measurement approaches set standards for quality too low so that agencies supporting group home residents to go bowling every week can report the same outcomes as an agency that supports one person to join a book club that includes people based on their literary interests rather than disability labels. Ultimately, lack of delineation in measurement contributes to the confusion between face value “quality” and true quality services and supports for many people with disabilities and their families. This exploratory study adopts alternative approaches to quality measurement including co-production methods and systems theoretical framework in order to identify the factors that 1) lead to high-quality supports and, 2) differentiate high-quality services. Project researchers have partnered with community practitioners who are all committed to providing quality services and supports but vary in the degree to which they are actually able to provide them. The study includes two parts; first, an online survey distributed to more than 500 agencies that have demonstrated commitment to providing high-quality services; and second, four in-depth case studies with agencies in three United States and Israel providing a variety of supports to children and adults with disabilities. Results from both the survey and in-depth case studies were thematically analyzed and coded. Results show that there are specific factors that differentiate service quality; however meaningful quality measurement practices also require that researchers explore the contextual factors that contribute to quality. These not only include direct services and interactions, but also characteristics of service users, their environments as well as organizations providing services, such as management and funding structures, culture and leadership. Findings from this study challenge researchers, policy makers and practitioners to examine existing quality service standards and measurements and to adopt alternate methodologies and solutions to differentiate and scale up evidence-based quality practices so that all people with disabilities have access to services that support them to live, work, and enjoy where and with whom they choose.

Keywords: co-production, inclusion, independent living, quality measurement, quality supports

Procedia PDF Downloads 399

Authors: Ararat Khachatryan, Davit Mirzoyan

Abstract:

In sub micrometer technology, the aging phenomenon starts to have a significant impact on the reliability of integrated circuits by bringing performance degradation. For that reason, it is important to have a capability to evaluate the aging effects accurately. This paper presents an accurate aging measurement approach based on phase-locked loop (PLL) and voltage-controlled oscillator (VCO) circuit. The architecture is rejecting the circuit self-aging effect from the characteristics of PLL, which is generating the frequency without any aging phenomena affects. The aging monitor is implemented in low power 32 nm CMOS technology, and occupies a pretty small area. Aging simulation results show that the proposed aging measurement circuit improves accuracy by about 2.8% at high temperature and 19.6% at high voltage.

Keywords: aging effect, HCI, NBTI, nanoscale

Procedia PDF Downloads 359

Authors: Vito Telesca, Giuseppina A. Giorgio

Abstract:

The earth system is subject to a wide range of human activities that have changed the ecosystem more rapidly and extensively in the last five decades. These global changes have a large impact on human health. The relationship between extreme weather events and mortality are widely documented in different studies. In particular, a number of studies have investigated the relationship between climatological variations and the cardiovascular and respiratory system. The researchers have become interested in the evaluation of the effect of environmental variations on the occurrence of different diseases (such as infarction, ischemic heart disease, asthma, respiratory problems, etc.) and mortality. Among changes in weather conditions, the heat waves have been used for investigating the association between weather conditions and cardiovascular events and cerebrovascular, using thermal indices, which combine air temperature, relative humidity, and wind speed. The effects of heat waves on human health are mainly found in the urban areas and they are aggravated by the presence of atmospheric pollution. The consequences of these changes for human health are of growing concern. In particular, meteorological conditions are one of the environmental aspects because cardiovascular diseases are more common among the elderly population, and such people are more sensitive to weather changes. In addition, heat waves, or extreme heat events, are predicted to increase in frequency, intensity, and duration with climate change. In this context, are very important public health and climate change connections increasingly being recognized by the medical research, because these might help in informing the public at large. Policy experts claim that a growing awareness of the relationships of public health and climate change could be a key in breaking through political logjams impeding action on mitigation and adaptation. The aims of this study are to investigate about the importance of interactions between weather variables and your effects on human health, focusing on Italy. Also highlighting the need to define strategies and practical actions of monitoring, adaptation and mitigation of the phenomenon.

Keywords: climate change, illness, Italy, temperature, weather

Procedia PDF Downloads 247

Authors: Tahany W. Sadak

Abstract:

Presented work discusses research results concerning the effect of the heat treatment process. Thermal fatigue which expresses repeated heating and cooling processes affect the ductility or the brittleness of the material. In this research, 70 specimens of copper (1.5 mm thickness, 85 mm length, 32 mm width) are subjected to thermal fatigue at different conditions. Heating temperatures T_h are 100, 300 and 500 °C. Number of repeated cycles N is from 1 to 100. Heating time t_h =600 Sec, and Cooling time; t_C= 900 Sec.  Results are evaluated and then compared to each other and to that of specimens without subjected to thermal fatigue.

Keywords: copper, thermal analysis, heat treatment, hardness, thermal fatigue

Procedia PDF Downloads 434

Authors: Ahmed A. Alghamdi

Abstract:

Single-walled carbon nanotubes (SWCNTs) are an outstanding material for applications in thermoelectric power generation, nanoelectronics, electrochemical energy storage, photovoltaics, and light emission. They are ultra-lightweight and possess electrical as well as thermal conductivity, flexibility, and mechanical strength. SWCNT is applicable in water treatment, brine desalination, removal of heavy metal ions associated with pollutants, and oil-water separation. Carbon nanotube (CNT) is believed to tackle the trade-off issue between permeability, selectivity, and fouling issues in membrane filtration applications. Studying these CNT structures, as well as their interconnection in nanotechnology, assists in finding the precise position to be placed for water desalination. Reverse osmosis (RO) has been used globally for desalination, resulting in purified water. Thin film composite (TFC) membranes were utilized in the RO process for desalination. The sheet thickness increases the salt rejection and decreases the water flux when CNT is utilized as a support layer to this membrane. Thus, through a temperature-induced phase separation technique (TIPS), axially aligned SWCNT (AASWCNT) is fabricated, and its use enhances the salt rejection and water flux at short reaction times with a modified procedure. An evaluation was conducted and analogized with prior works in the literature, which exhibited that the prepared TFC membrane showed a better outcome.

Keywords: single-walled carbon nanotubes, thin film composite, axially aligned swcnt, temperature induced phase separation technique, reverse osmosis

Procedia PDF Downloads 51

Authors: Roslinda Nazar, Amin Noor, Khamisah Jafar, Ioan Pop

Abstract:

In this paper, the steady laminar three-dimensional boundary layer flow and heat transfer of a copper (Cu)-water nanofluid in the vicinity of a permeable shrinking flat surface in an otherwise quiescent fluid is studied. The nanofluid mathematical model in which the effect of the nanoparticle volume fraction is taken into account is considered. The governing nonlinear partial differential equations are transformed into a system of nonlinear ordinary differential equations using a similarity transformation which is then solved numerically using the function bvp4c from Matlab. Dual solutions (upper and lower branch solutions) are found for the similarity boundary layer equations for a certain range of the suction parameter. A stability analysis has been performed to show which branch solutions are stable and physically realizable. The numerical results for the skin friction coefficient and the local Nusselt number as well as the velocity and temperature profiles are obtained, presented and discussed in detail for a range of various governing parameters.

Keywords: heat transfer, nanofluid, shrinking surface, stability analysis, three-dimensional flow

Procedia PDF Downloads 287

Authors: R. O’Reilly Meehan, D. B. Murray

Abstract:

In many practical situations, bubbles are dispersed in a liquid phase. Understanding these complex bubbly flows is therefore a key issue for applications such as shell and tube heat exchangers, mineral flotation and oxidation in water treatment. Although a large body of work exists for bubbles rising in an unbounded medium, that of bubbles rising in constricted geometries has received less attention. The particular case of a bubble sliding underneath an inclined surface is common to two-phase flow systems. The current study intends to expand this knowledge by performing experiments to quantify the streamwise flow structures associated with a single sliding air bubble under an inclined surface in quiescent water. This is achieved by means of two-dimensional, two-component particle image velocimetry (PIV), performed with a continuous wave laser and high-speed camera. PIV vorticity fields obtained in a plane perpendicular to the sliding surface show that there is significant bulk fluid motion away from the surface. The associated momentum of the bubble means that this wake motion persists for a significant time before viscous dissipation. The magnitude and direction of the flow structures in the streamwise measurement plane are found to depend on the point on its path through which the bubble enters the plane. This entry point, represented by a phase angle, affects the nature and strength of the vortical structures. This study reconstructs the vorticity field in the wake of the bubble, converting the field at different instances in time to slices of a large-scale wake structure. This is, in essence, Taylor’s ”frozen turbulence” hypothesis. Applying this to the vorticity fields provides a pseudo three-dimensional representation from 2-D data, allowing for a more intuitive understanding of the bubble wake. This study provides insights into the complex dynamics of a situation common to many engineering applications, particularly shell and tube heat exchangers in the nucleate boiling regime.

Keywords: bubbly flow, particle image velocimetry, two-phase flow, wake structures

Procedia PDF Downloads 377

Authors: Keltoum Chahour, Mickael Binois

Abstract:

Due to a lack of standardization during the invasive fractional flow reserve (FFR) procedure, the index is subject to many sources of uncertainties. In this paper, we investigate -through simulation- the effect of the (FFR) device position and configuration on the obtained value of the (FFR) fraction. For this purpose, we use computational fluid dynamics (CFD) in a 3D domain corresponding to a diseased arterial portion. The (FFR) pressure captor is introduced inside it with a given length and coefficient of bending to capture the (FFR) value. To get over the computational limitations, basically, the time of the simulation is about 2h 15min for one (FFR) value; we generate a Gaussian Process (GP) model for (FFR) prediction. The (GP) model indicates good accuracy and demonstrates the effective error in the measurement created by the random configuration of the pressure captor.

Keywords: fractional flow reserve, Gaussian processes, computational fluid dynamics, drift

Procedia PDF Downloads 134

Authors: Valeriya Tyo, Serikbolat Yessengabulov

Abstract:

Regions with extreme climate conditions such as Astana city require energy saving measures to increase the energy performance of buildings which are responsible for more than 40% of total energy consumption. Identification of optimal building geometry is one of the key factors to be considered. The architectural form of a building has the impact on space heating and cooling energy use, however, the interrelationship between the geometry and resultant energy use is not always readily apparent. This paper presents a comparative case study of two prototypical buildings with compact building shape to assess its impact on energy performance.

Keywords: building geometry, energy efficiency, heat gain, heat loss

Procedia PDF Downloads 499

Authors: Sudhir Kumar, V. R. Sinha

Abstract:

Water in oil topical microemulsions of 5-FU were developed and optimized using face centered central composite design. Topical w/o microemulsion of 5-FU were prepared using sorbitan monooleate (Span 80), polysorbate 80 (Tween 80), with different oils such as oleic acid (OA), triacetin (TA), and isopropyl myristate (IPM). The ternary phase diagrams designated the microemulsion region and face centered central composite design helped in determining the effects of selected variables viz. type of oil, smix ratio and water concentration on responses like drug content, globule size and viscosity of microemulsions. The CCD design exhibited that the factors have statistically significant effects (p<0.01) on the selected responses. The actual responses showed excellent agreement with the predicted values as suggested by the CCD with lower residual standard error. Similarly, the optimized values were found within the range as predicted by the model. Furthermore, other characteristics of microemulsions like pH, conductivity were investigated. For the optimized microemulsion batch, ex-vivo skin flux, skin irritation and retention studies were performed and compared with marketed 5-FU formulation. In ex vivo skin permeation studies, higher skin retention of drug and minimal flux was achieved for optimized microemulsion batch then the marketed cream. Results confirmed the actual responses to be in agreement with predicted ones with least residual standard errors. Controlled release of drug was achieved for the optimized batch with higher skin retention of 5-FU, which can further be utilized for the treatment of many dermatological disorders.

Keywords: 5-FU, central composite design, microemulsion, ternanry phase diagram

Procedia PDF Downloads 479

Authors: David Edgar

Abstract:

To understand how the brain’s subconscious and conscious functions, we must conquer the physics of Unity, which leads to duality’s algorithm. Where the subconscious (bottom-up) and conscious (top-down) processes function together to produce and consume intelligence, we use terms like ‘time is relative,’ but we really do understand the meaning. In the brain, there are different processes and, therefore, different observers. These different processes experience time at different rates. A sensory system such as the eyes cycles measurement around 33 milliseconds, the conscious process of the frontal lobe cycles at 300 milliseconds, and the subconscious process of the thalamus cycle at 5 milliseconds. Three different observers experience time differently. To bridge observers, the thalamus, which is the fastest of the processes, maintains a synchronous state and entangles the different components of the brain’s physical process. The entanglements form a synchronous cohesion between the brain components allowing them to share the same state and execute in the same measurement cycle. The thalamus uses the shared state to control the firing sequence of the brain’s linear subconscious process. Sharing state also allows the brain to cheat on the amount of sensory data that must be exchanged between components. Only unpredictable motion is transferred through the synchronous state because predictable motion already exists in the shared framework. The brain’s synchronous subconscious process is entirely based on energy conservation, where prediction regulates energy usage. So, the eyes every 33 milliseconds dump their sensory data into the thalamus every day. The thalamus is going to perform a motion measurement to identify the unpredictable motion in the sensory data. Here is the trick. The thalamus conducts its measurement based on the original observation time of the sensory system (33 ms), not its own process time (5 ms). This creates a data payload of synchronous motion that preserves the original sensory observation. Basically, a frozen moment in time (Flat 4D). The single moment in time can then be processed through the single state maintained by the synchronous process. Other processes, such as consciousness (300 ms), can interface with the synchronous state to generate awareness of that moment. Now, synchronous data traveling through a separate faster synchronous process creates a theoretical time tunnel where observation time is tunneled through the synchronous process and is reproduced on the other side in the original time-relativity. The synchronous process eliminates time dilation by simply removing itself from the equation so that its own process time does not alter the experience. To the original observer, the measurement appears to be instantaneous, but in the thalamus, a linear subconscious process generating sensory perception and thought production is being executed. It is all just occurring in the time available because other observation times are slower than thalamic measurement time. For life to exist in the physical universe requires a linear measurement process, it just hides by operating at a faster time relativity. What’s interesting is time dilation is not the problem; it’s the solution. Einstein said there was no universal time.

Keywords: neural synchronization, natural intelligence, 99.95% IoT data transmission savings, artificial subconscious intelligence (ASI)

Procedia PDF Downloads 126

Authors: G .D. B. N. Kulasaooriya, H. B. S. Ariyarathne, I. Abeygunawardene, A. A. J. Rafarathne, B. V. Perera

Abstract:

Elephant is the largest resident of the wild and has small surface to volume ratio as well as less number of sweat glands which cause challenges to the thermoregulation of this mammal. However, this megaherbivore has adopted specialised meachanisms to maintain its thermal balance through behavioral adaptations, ear flapping and well anastomosed arterioles and venules of the ear. Nevertheless, little is known on the involvement of the skin in the process of thermoregulation. The present study was undertaken to monitor the water evaporation rate from the skin of unrestrained wild elephant calves throughout the day and to understand its importance in the thermoregulation. Seven baby elephants housed in the elephant transit home, Udawalawe were used. Ambient temparature, relative humidity (RH) and radiation heat load was monitored throughout the day of the study period. Similarly, surface temparature of the skin was taken at six points including lateral ear pinna, lateral body and the rump during the same period. The skin water evaporation was also measured from the same sites using cobolt chloride method. The surface are of the skin was determined by assigning geometrical shapes to each body part. The results showed that the ambient temperature gradually increased with the day reaching maximum around 3.00 pm. The relative humidity was lowest early in the morning. The radiation heat load did not show any significant change in the study period. The skin temperature was different among lateral ear pinna, lateral body and the rump where the highest temperature was on the rump and the lowest on the lateral ear pinna. The skin temperature gradually increase with increasing ambient temperature but there was not a strong correlation (R2 =53.53) between these two. The skin temperature had strong correlation with RH (p<0.05 R2 =70.84% ) but a significant relationship was not considered since the radiation heat load was not varying in large scale. The skin evaporative water loss had a weak negative correlation with ambient temperature (correlation coefficient= -0.01) whereas strong positive correlation with RH (correlation coefficient= 25.275 ) and no corelation with radiation heat load. It also appeared that skin water loss increases as the skin temperature increased. In the present study, it was observed that on average, skin of the baby elephant looses 403 g/m2/h of water. Based on these observations it can be concluded that a large volume of water is evaporated from the skin of baby elephants and evaporative heat loss may be contributing significantly to the thermoregulation. However, further investigation on the influence of environmental factors on evaporative heat loss has to be conducted to understand the thermoregulatory mechanisms of the baby elephant.

Keywords: thermoregulation, behavioral adaptations, evaporation, elephant

Procedia PDF Downloads 378

Authors: M. Venegas, M. De Vega, N. García-Hernando

Abstract:

Absorption cooling chillers have received growing attention over the past few decades as they allow the use of low-grade heat to produce the cooling effect. The combination of this technology with solar thermal energy in the summer period can reduce the electricity consumption peak due to air-conditioning. One of the main components, the absorber, is designed for simultaneous heat and mass transfer. Usually, shell and tubes heat exchangers are used, which are large and heavy. Cooling water from a cooling tower is conventionally used to extract the heat released during the absorption and condensation processes. These are clear inconvenient for the generalization of the absorption technology use, limiting its benefits in the contribution to the reduction in CO2 emissions, particularly for the H2O-LiBr solution which can work with low heat temperature sources as provided by solar panels. In the present work a promising new technology is under study, consisting in the use of membrane contactors in adiabatic microchannel mass exchangers. The configuration here proposed consists in one or several modules (depending on the cooling capacity of the chiller) that contain two vapour channels, separated from the solution by adjacent microporous membranes. The solution is confined in rectangular microchannels. A plastic or synthetic wall separates the solution channels between them. The solution entering the absorber is previously subcooled using ambient air. In this way, the need for a cooling tower is avoided. A model of the configuration proposed is developed based on mass and energy balances and some correlations were selected to predict the heat and mass transfer coefficients. The concentration and temperatures along the channels cannot be explicitly determined from the set of equations obtained. For this reason, the equations were implemented in a computer code using Engineering Equation Solver software, EES™. With the aim of minimizing the absorber volume to reduce the size of absorption cooling chillers, the ratio between the cooling power of the chiller and the absorber volume (R) is calculated. Its variation is shown along the solution channels, allowing its optimization for selected operating conditions. For the case considered the solution channel length is recommended to be lower than 3 cm. Maximum values of R obtained in this work are higher than the ones found in optimized horizontal falling film absorbers using the same solution. Results obtained also show the variation of R and the chiller efficiency (COP) for different ambient temperatures and desorption temperatures typically obtained using flat plate solar collectors. The configuration proposed of adiabatic membrane-based absorber using ambient air to subcool the solution is a good technology to reduce the size of the absorption chillers, allowing the use of low temperature solar heat and avoiding the need for cooling towers.

Keywords: adiabatic absorption, air-cooled, membrane, solar thermal energy

Procedia PDF Downloads 285

Authors: Brahim Fersadou, Henda Kahalerras

Abstract:

This work deals with the problem of MHD mixed convection in a completely porous and differentially heated vertical channel. The model of Darcy-Brinkman-Forchheimer with the Boussinesq approximation is adopted and the governing equations are solved by the finite volume method. The effects of magnetic field and buoyancy force intensities are given by the Hartmann and Richardson numbers respectively, as well as the Joule heating represented by Eckert number on the velocity and temperature fields, are examined. The main results show an augmentation of heat transfer rate with the decrease of Darcy number and the increase of Ri and Ha when Joule heating is neglected.

Keywords: heat sources, magnetic field, mixed convection, porous channel

Procedia PDF Downloads 377

Authors: Amira Zrelli, Tahar Ezzeddine

Abstract:

Measurement and monitoring of temperature, humidity and strain variation are very requested in great fields and areas such as structural health monitoring (SHM) systems. Currently, the use of fiber Bragg grating sensors (FBGS) is very recommended in SHM systems due to the specifications of these sensors. In this paper, we present the theory of Bragg sensor, therefore we try to measure the efficient variation of strain, temperature and humidity (SV, ST, SH) using Bragg sensor. Thus, we can deduce the fundamental relation between these parameters and the wavelength of Bragg sensor.

Keywords: Fiber Bragg Grating Sensors (FBGS), strain, temperature, humidity, structural health monitoring (SHM)

Procedia PDF Downloads 316

Authors: Kira Toxopeus, Kamran Siddiqui

Abstract:

Channel flows are common in a wide range of engineering applications. In some types of channel flows, particularly the ones involving chemical or biological processes, the control of the flow temperature is crucial to maintain the optimal conditions for the chemical reaction or to control the growth of biological species. This often becomes an issue when the flow experiences temperature fluctuations due to external conditions. While active heating and cooling could regulate the channel temperature, it may not be feasible logistically or economically and is also regarded as a non-sustainable option. Thermal energy storage utilizing phase change material (PCM) could provide the required thermal regulation sustainably by storing the excess heat from the channel and releasing it back as required, thus regulating the channel temperature within a range in the proximity of the PCM melting temperature. However, in designing such systems, the configuration of the PCM storage within the channel is critical as it could influence the channel flow dynamics, which would, in turn, affect the heat exchange between the channel fluid and the PCM. The present research is focused on the investigation of the flow dynamical behavior in the channel during heat transfer from the channel flow to the PCM thermal energy storage. Offset vertical columns in a narrow channel were used that contained the PCM. Two different column shapes, square and circular, were considered. Water was used as the channel fluid that entered the channel at a temperature higher than that of the PCM melting temperature. Hence, as the water was passing through the channel, the heat was being transferred from the water to the PCM, causing the PCM to store the heat through a phase transition from solid to liquid. Particle image velocimetry (PIV) was used to measure the two-dimensional velocity field of the channel flow as it flows between the PCM columns. Thermocouples were also attached to the PCM columns to measure the PCM temperature at three different heights. Three different water flow rates (0.5, 0.75 and 1.2 liters/min) were considered. At each flow rate, experiments were conducted at three different inlet water temperatures (28ᵒC, 33ᵒC and 38ᵒC). The results show that the flow rate and the inlet temperature influenced the flow behavior inside the channel.

Keywords: channel flow, phase change material, thermal energy storage, thermal regulation

Procedia PDF Downloads 140

Authors: Cleyton S. Stampa

Abstract:

This paper addresses the perspectives of using low melting point metals (LMPMs) as phase change materials (PCMs) in latent thermal energy storage (LTES) units, through a numerical approach. This is a new class of PCMs that has been one of the most prospective alternatives to be considered in LTES, due to these materials present high thermal conductivity and elevated heat of fusion, per unit volume. The chosen type of LTES consists of several horizontal parallel slabs filled with PCM. The heat transfer fluid (HTF) circulates through the channel formed between each two consecutive slabs on a laminar regime through forced convection. The study deals with the LTES charging process (heat-storing) by using pure gallium as PCM, and it considers heat conduction in the solid phase during melting driven by natural convection in the melt. The transient heat transfer problem is analyzed in one arbitrary slab under the influence of the HTF. The mathematical model to simulate the isothermal phase change is based on a volume-averaged enthalpy method, which is successfully verified by comparing its predictions with experimental data from works available in the pertinent literature. Regarding the convective heat transfer problem in the HTF, it is assumed that the flow is thermally developing, whereas the velocity profile is already fully developed. The study aims to learn about the effect of the solid subcooling in the melting rate through comparisons with the melting process of the solid in which it starts to melt from its fusion temperature. In order to best understand this effect in a metallic compound, as it is the case of pure gallium, the study also evaluates under the same conditions established for the gallium, the melting process of commercial paraffin wax (organic compound) and of the calcium chloride hexahydrate (CaCl₂ 6H₂O-inorganic compound). In the present work, it is adopted the best options that have been established by several researchers in their parametric studies with respect to this type of LTES, which lead to high values of thermal efficiency. To do so, concerning with the geometric aspects, one considers a gap of the channel formed by two consecutive slabs, thickness and length of the slab. About the HTF, one considers the type of fluid, the mass flow rate, and inlet temperature.

Keywords: flat slab, heat storing, pure metal, solid subcooling

Procedia PDF Downloads 141

Authors: Tzu-Ping Lin, Shing-Ru Yang

Abstract:

Climate change has a significant impact on human living environment, while the traditional settlement may suffer extreme thermal stress due to its specific building type and living behavior. This study selected Lutaoyang, which is the largest settlement in mountainous areas of Tainan County, for the investigation area. The microclimate parameters, such as air temperature, relative humidity, wind speed, and mean radiant temperature. The micro climate parameters were also simulated by the ENVI-met model. The results showed the banyan tree area providing good thermal comfort condition due to the shading. On the contrary, the courtyard (traditionally for the crops drying) surrounded by low rise building and consisted of artificial pavement contributing heat stress especially in summer noon. In the climate change simulations, the courtyard will become very hot and are not suitable for residents activities. These analytical results will shed light on the sustainability related to thermal environment in traditional settlements and develop adaptive measure towards sustainable development under the climate change challenges.

Keywords: thermal environment, traditional settlement, ENVI-met, Taiwan

Procedia PDF Downloads 479

Authors: Sih-Li Chen, Chih-Hao Chen, Chi-Tong Chan

Abstract:

Poor ventilation and high carbon dioxide (CO2) concentrations lead to the formation of sick buildings. This problem cannot simply be resolved by introducing fresh air from outdoor environments because this creates extra loads on indoor air-conditioning systems. Desiccants are widely used in air conditioning systems in tropical and subtropical regions with high humidity to reduce the latent heat load from fresh air. Desiccants are usually used as a packed-bed type, which is low cost, to combine with air-conditioning systems. Nevertheless, the pressure drop of a packed bed is too high, and the heat of adsorption caused by the adsorption process lets the temperature of the outlet air increase, bringing about an extra heat load, so the high pressure drop and the increased temperature of the outlet air are energy consumption sources needing to be resolved. For this reason, the gas-solid fluidised beds that have high heat and mass transfer rates, uniform properties and low pressure drops are very suitable for use in air-conditioning systems.This study experimentally investigates the performance of silica gel fluidized bed device which applying to an air conditioning system. In the experiments, commercial silica gel particles were filled in the two beds and to form a fixed packed bed and a fluidized bed. The results indicated that compared to the fixed packed bed device, the total adsorption and desorption by amounts of fluidized bed for 40 minutes increased 20.6% and 19.9% respectively when the bed height was 10 cm and superficial velocity was set to 2 m/s. In addition, under this condition, the pressure drop and outlet air temperature raise were reduced by 36.0% and 30.0%. Given the above results, application of the silica gel fluidized bed to air conditioning systems has great energy-saving potential.

Keywords: fluidized bed, packed bed, silica gel, adsorption, desorption, pressure drop

Procedia PDF Downloads 536

Authors: Basavaraj Vadavadagi, Satishkumar Shekhawat

Abstract:

Interstitial free steels posses better formability and have many applications in automotive industries. Forming limit diagrams (FLDs) indicate the formability of materials which can be determined by experimental and finite element (FE) simulations. FLDs were determined experimentally by LDH test, utilizing optical strain measurement system for measuring the strains in different width specimens and by FE simulations in Interstitial Free (IF) and Interstitial Free High Strength (IFHS) steels. In this study, the experimental and FE simulated FLDs are compared and also the stress based FLDs were investigated.

Keywords: forming limit diagram, limiting dome height, optical strain measurement, interstitial

Procedia PDF Downloads 232

Authors: Madina Alimova, Margulan Ibraimov, Ayan Tileu

Abstract:

The paper describes methods for obtaining porous structures with the properties of a silicon-based memristor and explains the electrical properties of porous silicon films. Based on the results, there is a positive shift in the current-voltage characteristics (CVC) after each measurement, i.e., electrical properties depend not only on the applied voltage but also on the previous state. After 3 minutes of rest, the film returns to its original state (reset). The method for obtaining a porous silicon nanofilm with the properties of a memristor is simple and does not require additional effort. Based on the measurement results, the typical memristive behavior of the porous silicon nanofilm is analyzed.

Keywords: porous silicon, current-voltage characteristics, memristor, nanofilms

Procedia PDF Downloads 130

Authors: Ahmad Hashim, Zarizi Ab Rahman

Abstract:

Measurement of body composition via a field method has the most popular instruments which are used to estimate the percentage of body fat. Among the instruments used are the Body Mass Index, Bio Impedance Analysis and Skinfold Test. All three of these instruments do not involve high costs, do not require high technical skills, are mobile, save time, and are suitable for use in large populations. Because all three instruments can estimate the percentage of body fat, but it is important to identify the most appropriate instruments and have high reliability. Hence, this study was conducted to determine the reliability and convergent validity of the instruments. A total of 40 students, males and females aged between 13 and 14 years participated in this study. The study found that the test retest and Pearson correlation coefficient of reliability for the three instruments is very high, r = .99. While the inter class reliability also are at high level with r = .99 for Body Mass Index and Bio Impedance Analysis, r = .96 for Skin fold test. Intra class reliability coefficient for these three instruments is too high for Body Mass Index r = .99, Bio Impedance Analysis r = .97, and Skin fold Test r = .90. However, Standard Error of Measurement value for all three instruments indicates the Body Mass Index is the most appropriate instrument with a mean value of .000672 compared with other instruments. The findings show that the Body Mass Index is an instrument which is the most accurate and reliable in estimating body fat percentage for the population studied.

Keywords: reliability, validity, body mass index, bio impedance analysis and skinfold test

Procedia PDF Downloads 336