Dong Chen

Abstracts

3 Investigation of Heat Transfer Mechanism Inside Shell and Tube Latent Heat Thermal Energy Storage Systems

Authors: Dong Chen, Saeid Seddegh, Xiaolin Wang, Alan D. Henderson, Oliver Oims

Abstract:

The main objective of this research is to study the heat transfer processes and phase change behaviour of a phase change material (PCM) in shell and tube latent heat thermal energy storage (LHTES) systems. The thermal behaviour in a vertical and horizontal shell-and-tube heat energy storage system using a pure thermal conduction model and a combined conduction-convection heat transfer model is compared in this paper. The model is first validated using published experimental data available in literature and then used to study the temperature variation, solid-liquid interface, phase distribution, total melting and solidification time during melting and solidification processes of PCMs. The simulated results show that the combined convection and conduction model can better describe the energy transfer in PCMs during melting process. In contrast, heat transfer by conduction is more significant during the solidification process since the two models show little difference. Also, it was concluded that during the charging process for the horizontal orientation, convective heat transfer has a strong effect on melting of the upper part of the solid PCM and is less significant during melting of the lower half of the solid PCM. However, in the vertical orientation, convective heat transfer is the same active during the entire charging process. In the solidification process, the thermal behavior does not show any difference between horizontal and vertical systems.

Keywords: Melting, Solidification, natural convection, shell and tube heat exchanger, phase change material, latent heat thermal energy storage

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2 Research on the Evolutionary Character of Capital in Rural Areas and Counter-Measure of Planning

Authors: Dong Chen, Han Song, Tingting Wei

Abstract:

The combination of capital and rural areas in China has shown its great significance in promoting urban-rural integration and new-style urbanization, enhancing regional capacity for sustainable rural development and optimizing human settlement environment. The purpose of this study is to find capital operation mechanism in rural area and rural planning guidance in China. Based on case studies in Chinese rural areas, two types of capital operation mechanism in rural areas are summed up: intervention in the field of agriculture promoting the upgrading and innovation of agricultural industry chain, intervention in rural life and leisure areas updating rural connotation and form. In the light of experiences in Japan and Taiwan, it is proposed that government's norms and guidance, rural investment intensity and rural self-organization are three important factors for capital to drive rural development. It is also found that the unique land tenure and rural governance tradition are two important factors effecting the combination of capital and rural regions in China, which requires full attention in rational policy-making and rural planning. It comes to a conclusion as four directions of the overall reform of the rural planning: targeting at enhancing the viability of rural and sustainable capacity, encouraging differences in investment incentives and planning policies, providing land usage in the rural areas with planning support and reforming the village system. Directional guidance is also made for different types of capital investments, suggesting that capital should be rooted in agriculture and rural land to benefit farmers and update human settlements.

Keywords: capital, rural areas, Rural Planning, rural governance

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1 Research on Characteristics and Inventory Planning Counter-Measure of Mature Industrial Zones in the Background of China's New Normal

Authors: Dong Chen, Han Song, Tingting Wei

Abstract:

Industrial zones have made significant contributions to the economic development of Chinese urban areas for decades. In the background of China's New Normal, numbers of mature industrial zones are stepping into a new stage of inventory development instead of increment development. The aim of this study is to discover new characteristics and problems and corresponding inventory planning guidance of mature industrial zones. A case of Yangzhou Hi-Tech Industrial Development Zone is reported in this study. Based on a historical analysis and data analysis of land-use, it is found that land-use of the zone is near saturation and signs of land updating have begun to appear. It is observed that the zone is facing problems including disorder of land development, low economic productivity and single function. Through the data of economic output, tax contribution, industrial category, industry life cycle and environmental influence, a comprehensive assessment based on two dimensions, economic benefits and industrial matchup, is made upon every parcel in the zone. According to the assessment, the zone is divided into spatial units of the update with specific planning guidance. It comes to a conclusion as four directions of inventory planning guidance in mature industrial zones: moving industries with poor economic benefit and negative environmental influence, adding urban function and new industrial function to the zone, optimizing the function of important space, and restricting the mass layout of the real estate industry to provide space for industrial upgrading.

Keywords: Inventory Planning, land-use, China's new normal, mature industrial zones

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