Applied Mechanics and Materials Vols. 672-674

Abstract: According to the principles of air and heat balance and aiming at air-conditioning load time delay mechanism, the boot time for air-conditioning system operation is controlled to satisfy the demand of air-conditioned environment without wasting energy [1].

Abstract: In the traditional concept, the performance of internal shading system is inferior compared with that of external one. In actual projects, however, external shadings are subject to severe limitations due to the damage of artistic appearance in building design, the high initial investment and the difficult maintenance in the late stage. Besides, in residential buildings the shading measures are single, mainly including external and internal shadings, and the window types are quite similar. Therefore, through theoretical calculation and experimental test in this paper, the feasibility of substituting the internal shading system with high reflectivity for the external one in residential buildings was analyzed. Such replacement can reduce the cost of shading system and maintain the artistic appearance of building facades. Thus, there are few limitations on the appearance design of a building considering the shading performance.

Abstract: Last years much attention is paid to energy efficiency and conservation in organizations. But energy saving at industrial scale starts with heat energy saving, electricity and water in each apartment and every home. The article describes the basic rules of saving heat, electricity and water at home. Also described the means of promoting energy saving and energy efficiency among the population. Special attention is paid to the training of the population and advanced training of specialists at field of energy conservation.

Abstract: Three operating modes of district heating system are introduced and the operating parameters are compared. To find out the most energy-saving one, an experiment is carried out in a cogeneration plant. An operating mode using variable frequency circulating pump for flow control at a constant supply and return water temperature difference is proposed. The conclusion shows that using variable frequency circulating pump is a more energy-saving method.

Abstract: By considering the momentum source term of surface tension and the source term of heat transfer in gas-liquid two phase flow, a computational model based on the VOF was established to discuss the rules of the temperature outside tube in the evaporative air cooler.The result shows that under a wind velocity and spray density, the temperature of water near the wall dropped sharply at first, with wall distance increasing, finally to environmental temperature, and with annular angle increase, the temperature of water film increases. And the higher the wind speed, the higher the water film temperature, but the changes of wind speed has little influence on the temperature within less than 60 º angle. The smaller the spray density, the higher water film temperature.

Abstract: Superconducting Magnetic Energy Storage (SMES) system use conductive coils made of superconductor wire to store energy, its application entirely depends on the design and development of superconducting magnet, as the magnetic storage element, during the operation of the superconducting magnet generates relatively strong magnetic field. In this paper, a 1MJ class single solenoidal SMES with Bi2223/Ag conductor is presented. On the basis of electromagnetic theory, subsequently infers mathematical model of magnetic field distribution by ANSYS finite element analysis software, modeling a two-dimensional electromagnetic analysis of 44 double pancakes to get the magnetic field distribution patterns. The results of the analysis provide a reference for the structural design, optimization of a superconducting magnet and shielding of stray magnetic field.

Abstract: The flows generated by lifting force can be met as in environment as in a number of technical devices. These flows emerge due to volume force which depends on the difference in densities caused by transfer of thermal energy as a result of temperature non-uniformity. Convection flows, which cause heat transfer between surfaces and air, emerge near heated or cooled surfaces. The densities of both liquid and gas depend on temperature. Therefore with the temperature gradient in liquid or gas mass forces are different at different points. This causes motion of gas or liquid which can be defined by direction of the field of mass forces, distribution of temperature in liquid and geometric shape of volume.

Abstract: Energy saving has become a consensus and urgency problems to solve for China and the world. The proposal of Smart Grid based on this. A large number of distributed power penetratione as an important feature of the future smart grid has become an irreversible trend, especially in the distribution network, the economic ,efficiency, and the advantages of the green environmental will be reflected more perfect. A large number of distributed power access also produce many adverse effects on the existing distribution network, that it is difficult to reflect the immediate advantages of distributed power supply. Because of this,plug and play of the distributed power become the hot spot of research in this field. This paper will be another point of view to discuss the distributed power access to the distributed grid side.with plug-and-play architecture.By the research of theoretical origin,the formation of plug-and-play and the expansion in the field of distributed power access distribution network.This paper puts forward the system's point of view to discusses the three models and their own characteristics for the distributed power access to distribution network, hope it will lay theoretical foundation of the Plug and Play technology for the eventual realization these models in the future by the power electronics, communications, control theory,and so on.

Abstract: The technology of application of the liquefied gas for the centralized providing with energy resources of a complex of building remote from network energy resources is considered in this work, the economic-mathematical model of the first approach of the concept of the device of the settlement, allowing to determine the cost of received energy and equipment payback periods is offered.

Abstract: In this paper, a three-dimension model for the vanadium redox flow battery was established to simulate its mass transfer. The distribution of VO₂⁺and VO²⁺ in positive electrode area, the distribution of V²⁺ and V³⁺ in the negative electrode area, and the influences of flow velocity, temperature and the electrolyte concentration on the mass transfer are analyzed. The results show that the mass fraction of VO₂⁺ and V²⁺ decrease while those of VO²⁺and V³⁺increase along the channel direction; the species concentration under the ridge is lower than that under the flow channel. The flow velocity of electrolyte affects the mass distribution at the entrance of the cell, and hardly affects the electrochemical reaction rate; Increase of the temperature accelerates the electrochemical reaction rate; the electrolyte concentration affects both of the mass distribution and the number of ions. The study has great significance both on the optimization of vanadium redox flow battery and its application.