Abstract: This paper introduces the design of solar water ring heat pump heating system. Utilizing the solar collector system installed on the roof of the center, winter serves as the heat source of the water ring heat pump, and the other three quarters provide domestic hot water to achieve the comprehensive utilization of solar energy throughout the year and improve the thermal efficiency of the solar collector during winter operation. Keywords: solar water ring heat pump heating 1 Overview With the development of economy and continuous improvement of people's living standards, China is facing more and more energy pressure, especially for heating and air-conditioning building energy consumption has become a cause of power shortage in many cities in our country. Earth's fossil fuels - coal, oil, natural gas, etc. will gradually mining depletion, the development of renewable energy including solar energy, wind power, including the task has been very urgent. Therefore, while improving the applied technology of solar thermal utilization, we should actively create the conditions to popularize and apply the existing mature technologies in practical projects so as to accumulate experience and improve, improve and play a role of model and demonstration through practice. Net Elegant Group Entertainment Center is a catering, bathing, entertaining entertainment services integrated, which is characterized by a large amount of hot water, the indoor environment throughout the year demanding high comfort for the heating, air conditioning and hot water supply energy consumption Big. In order to reduce operating costs as much as possible and reduce the burden on owners, we propose a solar water ring heat pump heating program, the use of solar energy for winter heating, spring, summer and autumn supply of domestic hot water, make full-year comprehensive utilization, and improve solar energy The thermal efficiency of the heat collection system in winter has been recognized and adopted by the owners and the preliminary design has now been completed. 2 solar collector system design The effective gain of solar collector system is mainly affected by two factors, one is the thermal performance of the solar collector itself and the other is the total area of ​​the installed solar collector. In the same solar energy resources and climatic conditions, in order to obtain the required heat gain, good thermal performance of solar collectors need to install a small area, you must choose a high efficiency collector, in order to reduce the initial investment, access to maximize the return on investment. In order to meet the requirements of winter heating and three-quarter supply of hot water, the solar collector system should be a closed cycle system, which requires that solar collectors should have higher pressure bearing capacity. Therefore, in order to ensure the efficient, safe and reliable operation of the solar collector system, we adopted the all-glass vacuum tube U-tube solar collector made by Tsinghua Sunshine Group. The utility model is characterized in that a U-shaped copper tube is arranged in the whole glass vacuum tube as a channel of the heat-collecting medium, so that the pressure-bearing capacity of the collector is raised to 1.0Mpa. The solar thermal collector in the international authority Swiss Rapperswil solar thermal testing center for the performance test results to determine the size of solar collectors provided the basis. All-glass vacuum tube U-tube solar collector instantaneous collector efficiency is: η = 0.5608- 0.92 (Tm-Ta) / G · 0.010 (Tm-Ta) 2 / G G - solar irradiance Tm - solar collector average water temperature Ta - ambient temperature Using the instantaneous heat-collection efficiency equation and the meteorological statistic data of 20 years in Beijing, we calculated the annual maximum temperature in summer and summer under extreme conditions (January, July, Irradiance) and general conditions (January, July, the total hourly average irradiance) under the solar collector heat collection efficiency, and the cumulative daily calorie per unit area, that is, the unit area of ​​the solar collector Nissan Hot water. The results of a comprehensive analysis, and with reference to solar water heater business experience in the past, according to the maximum hour hot water consumption, to determine the basic requirements of the total solar collector area. To determine the solar collector area more accurate method, should be on the solar hot water system thermal performance testing, thermal performance test results obtained based on the use of standard annual solar irradiance and the average ambient temperature , Calculated annual solar heat per unit area per day, that is, the daily unit area of ​​?? solar hot water. The "15" national science and technology research project in charge of air-conditioning will develop calculation software that can predict the annual thermal performance of solar water heating system. After the project was completed in the end of 2004, it will provide a convenient calculation tool for the design of solar thermal system. 2.2 solar collector system design The solar hot water generated by the solar collector system of this project is used as heating source of water ring heat pump in winter and used for domestic hot water supply in spring, summer and autumn. In this way, the solar energy can be comprehensively utilized throughout the year and the thermal efficiency of the solar heat collecting system during winter operation can be improved because the water temperature required by the water ring heat pump is lower. According to the building conditions, the solar collector system consists of two subsystems, with solar collector areas of 160 m2 and 260 m2 respectively, with a total area of ​​420 m2. Generally, the annual solar collector inclination for hot water supply should be equal to the local latitude. The latitude of Beijing is 40 degrees. However, this project is more conducive to winter heat collection and will increase the installation inclination to 45 degrees. In winter, the solar elevation angle Low, collector inclination increases, the solar collector surface of the incident angle of direct radiation decreases, the corresponding increase in solar radiation. According to the summer conditions to determine the size of the solar hot water tank, hot water tank for each sub-system volume of 15m3, the total volume of 30m3. Solar collector operating medium for antifreeze, to solve winter frost problems. Therefore, the use of indirect heating closed system, heat collecting medium through the plate heat exchanger to heat the water tank, circulating pump on the system back to the pipeline set pressure expansion tank. System schematic diagram shown in Figure 1. Solar hot water tank solar collector system and solar hot water supply system phase contact. Each solar collector system set 2 sets of solar collector circulation pump, one with a prepared, a total of four sets of solar collector circulation pump; solar hot water supply system set up two solar hot water supply pumps, one with a prepared. Two manual shut-off valves are provided on the loop of the solar hot water supply system to switch the water supply functions in winter and the other three seasons. Valve 1 is turned on in winter and closed in the other three quarters. The solar hot water is supplied to the water ring heat pump circuit. Valve 2 is closed in winter , The other three quarters open, hot water supply solar hot water loop. In order to achieve solar hot water supply in winter hot water, in the other three quarters as a water ring heat pump hot water heat source function transformation. Conventional heat source for domestic hot water supply and winter heating is gas boiler, domestic hot water system adopts positive displacement heat exchanger, and heating system adopts plate heat exchanger. In order to make full use of the solar heat, the solar hot water in the spring, summer and autumn is the water supply of the positive displacement heat exchanger, and is changed to tap water supply only in winter. Therefore, in the volumetric heat exchanger water supply pipeline also set up two manual shut-off valve for winter and the other three seasons of water supply function switch, the valve 1 open in winter, the other three seasons closed, tap water to the positive displacement heat exchanger water; Valve 2 closed in the winter, the other three quarters open, the solar water to the positive displacement heat exchanger water. As the entertainment center of hot water usage varies greatly with the size of the passenger flow, in order to prevent long-term water consumption is small and cause solar water heating system, the water temperature is too high, or even vaporization phenomenon in the system of each row of collector tubes On the road are set automatic deflation valve to ensure the safety of the system. In order to prevent hot water in the plate heat exchanger fouling, each plate heat exchanger on the import pipeline need to install an electronic descaling instrument. In order to fully tap the energy-saving benefits, the selected gas-fired boiler should have good self-control function, and can automatically adjust the heating output of the boiler according to the change of the solar hot water supply temperature of the positive displacement heat exchanger and the plate heat exchanger so as to really save energy. 3 solar heating system operation control Solar collector system uses temperature control loop in the solar hot water tank and each solar collector subsystem are set temperature sensors, solar collector system when the water temperature T1 higher than the hot water tank When the water temperature T2, the collector circulation pump starts, collector system operation, through the solar collector heated hot water into the hot water tank. When the solar collector system water temperature T1 is lower than the heat storage tank water temperature T2, the heat collection circulating pump is closed and the heat collecting system is stopped to prevent the cold water with the temperature lower than T2 from entering the water tank, so as to avoid nighttime and overcast, rainy and snowy days The unnecessary heat loss. Solar hot water tank is the direct use of tap water, set in the tank level controller, through the high and low water level signal to control the water supply pipe on the solenoid valve, the water tank level dropped to the set low water level, the solenoid valve open Replenishment; Replenishment to reach the set high water level, the solenoid valve closed to stop water. In the spring, summer and autumn quarters, even if there is no solar hot water, the volumetric heat exchanger tap water replenishment through the solar hot water tank to be supplemented. Spring, summer and autumn solar hot water supply pumps in accordance with the volumetric heat exchangers control the way to start and stop the water, the need for replenishment, the signal control of solar hot water pump start, stop pumping water. In winter, the volumetric heat exchanger is replenished by tap water. When the water is replenished, the solenoid valve on the signal control tap water line is turned on and the solenoid valve is closed after the water is full. In winter operation, the solar hot water heats the hot water of the water ring heat pump through the plate heat exchanger, and the water temperature of the solar hot water tank may be lower than that of the water ring heat pump at night when the solar heat supply in the cloudy, rainy and snowy days is insufficient. Air conditioning system heating backwater temperature. Therefore, the solar hot water supply pump start and stop, should be based on the solar hot water tank temperature to control. Otherwise, the heating and water return can not only get the heat from the heat exchanger, but may lose heat, causing the temperature of the heating and return water to continue to decrease. The temperature control of water tank for start and stop of the water pump is closely related to the design temperature of the water return heat pump. The design temperature of the water return heat pump in the project is 22 ℃. Therefore, the control of the operation of the solar hot water pump is: When the water temperature of the solar hot water tank is lower than 25 ° C, the water supply pump stops, and when the water temperature of the solar hot water tank reaches 30 ° C, the water supply pump is restarted; thus, the heating water return is always obtained through the heat exchanger. references: Cpu Server,Cpu Cooler Parts,Gpu Aluminum Cooling Plate,Copper Heat Sink Suzhou Wint Electric Co., Ltd , https://www.wintocool.com
2.1 The total area of ​​solar collector to determine
Figure 1: Solar collector system diagram
(1) Wang Changgui. Zheng Ruicheng. The application of new energy in buildings. Beijing: China Electric Power Press, 2003