Guohui Feng

Study on Thermal Storage Performance of Phase Change Heat Storage Type Air Conditioning Cooling Reservoir in Civil Air Defense Engineering

The heat storage capacity of the existing air conditioning cooling reservoir is not enough due to the increase in equipment and personnel. The problem of insufficient heat storage capacity can be solved by using phase change energy storage technology. In this paper, the model experiment of air conditioning cooling water reservoir is established. Different number of phase change heat storage modules (PCHSMs) of 0, 104, 208, 312, 412, 512, and 614 are separately put into the reservoir, and then the heat storage capacity of the reservoir is tested. The test results indicate that it takes 17.37 h for the outlet water temperature of the reservoir to rise from 19° to 37° with 0 PCHSM, then the heat storage capacity of the reservoir increases as the number of PCHSMs increases. Comparing with the 0 PCHSM, the heat storage capacity of the reservoir increased 42.25 % with 614 PCHSMs. The heat storage capacity of reservoir can be obviously improved by using of PCHSMs. Therefore, the phase change heat storage type air conditioning cooling reservoir (PCACCR) is a meaningful way to guide reconstruction of existing reservoirs and construction of new reservoirs.

Macro-Encapsulated PCM Cylinder Module Based on Paraffin and Float Stones

Organic phase change material (PCM) with macro-encapsulation is attractive in energy storage applications as it has relatively low cost. This study focuses on using PET plastic pipes to encapsulate paraffin and using low-cost float stones to increase the thermal conductivity of PCM modules as they have a special structure of high porosity. Float stones were immersed in the liquid PCM and an ultrasonic welding method used to prevent leakage of the PET plastic pipes. Scanning electron microscopy (SEM) was used to discover the appearance of the composite PCM. The thermal performance of the PCM cylinder module was analyzed through experimental tests of a constant-temperature water bath and numerical simulations. The result indicates that this PCM Ccylinder module is superior in thermal energy storage compared with the reference module even though fewer PCM was contained and the latent heat loss is considerable. The pipe diameter is an important parameter when using this kind of PCM cylinder module in water tanks.

Survey of Window-Opening Behavior of Severe Cold Area in Winter and Relevant Energy Consumption Analysis

In severe cold area with district heating, residents generally rely on window-opening behavior to improve indoor air quality, while heat loss becomes serious due to great temperature difference of inside and outside. Firstly, this paper acquired the basic information of Shenyang residential window-opening behavior though means of questionnaire. The second step is a comprehensive analysis using tracer gas measurement, computational fluid dynamics, and empirical models to acquire air change rate for typical rooms under conditions including window-opening custom and meteorological parameters. Based on all that, ventilation mass of a family apartment is predicted, and furthermore, we determined the ratio of the energy consumption to window-opening behavior in the coldest month. The research shows that most residents in Shenyang pay attention to indoor air quality and has window-opening behavior for certain time, and the present residential ventilation strategy is not only energy unfriendly but also unhealthy. This study provides important fundamental information for further ventilation strategy optimization in serve cold zone in China.

Analysis on the ground water heat pump technology

Ground source heat pump technology is a new energy technique. Its attractive advantages of high efficiency, environmental friendliness and energy conservation had made itself favored by people. But there exist some problems in the application as well, such as heat Penetration, wells blockage, subsidence of ground and so on, these problems seriously hindered the application of ground source heat pump system. This paper has made a brief analysis on the advantage and disadvantages of ground water heat pump.

Design and Analysis on a Kind of Compound Renewable Energy System for Heating

This paper aims to optimizing the conjunctive use of sewage source heat pump technology and solar hot water heating technology and improving the drawbacks when they are, respectively, applied. By adopting key technologies such as cooperation technology of sewage source heat pump technology and solar hot water heating technology, efficient phase change technology, scientific operation strategies, continuous automatic control of each equipment and others, the system realizes the efficient operation of sewage source heat pump units and solar hot water heating system, storage and delay of energy, full utilization of peak and valley time price policy which enables the system to gain the best heating effect and efficient operation of each equipment. We conduct a test and statistical analysis on the indoor comfort parameter, electricity, and water consumption of major equipments and the performance change of equipments at operation time for the system, and continuously optimize design conception for providing significant reference and guidance to the future field of renewable energy, finally completing the transition from nonrenewable energy to renewable energy.

Analysis of Microbiology Test of Air-Conditioning System in Severe Cold Area

Central air-conditioning system of Liaoning Provincial Museum has been taken as the target to study microbiology contamination since it is a typical public building. Three AHUs that conduct with different functional areas were considered as testing object in the museum, including constant temperature and humidity AHU B1, B2, and B3. Using microbiological method, six levels of impingement air microorganism sampler, fluorescent optical microscope, high-pressure steam sterilization pot, thermostatic incubator, thermostatic oven, biochemical incubator, and testing instruments are selected to test dust and air, which contain microbial organisms in the AHUs. Results show that the average product dust of the museum is 12.36 g/m2; the dust contains bacterial concentration in the microbiological is 85.2 × 104 cfu/m2, the air contains bacterial concentration in the microbiological is 568.19 cfu/m3, and the fungus concentration is 938.37 cfu/m3; the advantage strains in microbiologic is gram-positive bacterium; advantage strains in fungus is penicillium, aspergillums, branch spore mold.