| The western Sichuan region belongs to the cold region in China’s thermal engineering division,and there is a large demand for heating in winter.However,most areas in western Sichuan are still using traditional combustion or electric heating.This traditional heating method has disadvantages such as high energy consumption,low safety and poor environmental protection.Under the background of national leading clean energy heating,air source heat pump heating technology has been developed rapidly.The traditional split type hot air air source heat pump indoor unit has been widely used in China for many years,but the indoor unit has thermal comfort problems under the condition of hot air heating,such as hot temperature distribution and cold indoor temperature distribution.On the other hand,there are relatively few researches on indoor temperature distribution,indoor comfort and energy consumption when split type hot air air source heat pump is directly used in western Sichuan.To this end,use "Thirteen.Five national key research projects,the Tibetan plateau area,northwest and use of renewable energy heating air conditioning technology " as the platform,set up a demonstration project in western sichuan kangding city,according to a new type hot air source heat pump was measured and the theoretical analysis.Taking the new type terminal unit in residential building and the traditional wallmounted terminal unit in dormitory of Chongqing University as the research objects,the experimental tests under different operating conditions were carried out.The measured data were used as calculation conditions to carry out CFD simulation calculation,and the calculation results of different working conditions were obtained.The experimental results are compared with the simulation results.The results show that the error between the experimental results and the simulation results is less than 10%,and the two calculation models are reliable.Then the model of the traditional wall-mounted terminal is applied to the room of the demonstration project to simulate the air distribution under the same boundary conditions.The indoor air distribution formed by two kinds of end-heating systems was evaluated by using two comprehensive indexes of "temperature and velocity nonuniformity coefficient","PMV and ADPI".The results show that in the experimental conditions,the temperature non-uniformity coefficient is between 0.08～0.12,with a value of more than 56%,while in the traditional terminal heating,the indoor temperature nonuniformity coefficient is between 0.3～0.4,with a value of only about 33%.Therefore,the indoor temperature distribution is more uniform when the demonstration end unit is heating,and more measuring points meet the comfort requirements.The energy utilization coefficient was used to make the economic evaluation.The results show that the energy utilization coefficient of the demonstration terminal in heating is more than 1,while the energy utilization coefficient of the traditional terminal heating is less than 1,and the energy utilization ratio of the demonstration terminal unit is higher.When the demonstration end heating is adopted,the indoor air distribution at different set temperatures is evaluated by using the above evaluation indexes.The results show that the optimal conditions are when the thermal resistance of clothing is 1.32 clo,the metabolic rate is 1met,and the set temperature is 18℃.The energy consumption tests were carried out on the units of the demonstration project under different working conditions,and the hourly COP of the units during the experimental period was calculated.SPSS software is combined with experimental data to fit the theoretical calculation formula of COP under different operating conditions of the unit,and another set of experimental data is used to verify that the difference between the COP calculated by the prediction model and the actual operation COP of the unit is less than 5%,which verifies the reliability of the calculation formula of COP.The monitoring data of two heating seasons are analyzed,and the actual running time of the unit(compressor running time)corresponding to different set temperatures is counted,and the relationship between the actual running time of the unit and the indoor set temperature is given.It provides a basis for energy consumption prediction of similar projects.The annual energy consumption difference between electric heating and air source heat pump heating under different operating modes is compared.The results are as follows: when operating modes 1,2 and 3,the operating cost of air source heat pump heating is 1119.44,689.423 and 1125.4 yuan less than that of electric heating in the whole heating season,respectively;The operating energy consumption and cost differences of different setting temperatures in air source heat pump heating were compared.The results show that when the indoor setting temperature is 16,17,18 and 20℃,the power consumption per unit area in heating season of operation mode 1 is 31.73,33.79,37.69 and 48.31 k Wh/m~2,and the power consumption per unit area of operation mode 2 is 21.09,22.33,25.43 and 30.57 k Wh/m~2,respectively.The power consumption per unit area of operation mode 3 is 33.04,35.16,42.03 and 50.34 k Wh/m~2 respectively.It can be concluded that when the indoor setting temperature is between 16 ℃ and 20℃,the power consumption per unit area in the heating season changes as a quadratic function with the indoor setting temperature.The conclusions of this paper can provide suggestions and theoretical basis for the promotion of air source heat pump heating technology in western Sichuan,reasonable choice of hot air heating terminal and reasonable use. |
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