| Sichuan and Tibet are severely cold or cold regions and require heating in winter.In order to take into account the heating demand and environmental protection,the air source pump heating system has become a popular choice due to its high efficiency and environmental protection.This paper takes the air source heat pump heating system of an office building in a typical city in the Tibet area of Sichuan(Kangding City)as the research object.Through theoretical analysis,experimental testing,and TRNSYS simulation calculations,the operation performance of the air source heat pump heating system in Tibet is improved and improved.The operation control strategy has been studied,and the research work and results have important engineering practical value.First of all,this paper sorts out and analyzes the outdoor meteorological parameters of Kangding City,and lays the foundation of meteorological data for the analysis of the measured data of the heating system operation and the proposal of the system operation regulation strategy.In order to study the heating characteristics of the air source heat pump heating system in Tibet,Sichuan,this article carried out the "24 hours continuous heating,18:00 to 8:00 the next day,night heating" on the air source heat pump direct heating system of an office building in Kangding,Sichuan.,9:00～18:00 "Day heating" experimental operation test of three heating conditions,and at the same time analyzed the factors affecting the performance of the system.According to the analysis and analysis of the experimental test data: 1)The operating efficiency of the air source heat pump direct heating system in the Sichuan-Tibet District(Kangding City)is not ideal,and the energy efficiency of the system test operation is low;2)The impact of the air source heat pump direct heating system in the Sichuan-Tibet District The main influencing factors are outdoor ambient temperature,relative air humidity and unit load rate.Next,this paper conducts a fitting analysis on the change law of low-temperature air source heat pump heating capacity and coefficient of performance COP with outdoor ambient temperature,unit inlet water temperature,etc.,and obtains that the heating capacity and coefficient of performance COP of the low-temperature air source heat pump unit are at a relatively high level.Outdoor temperature range(6℃～15℃),unit inlet water temperature range(35℃～45℃).At the same time,this paper uses the mathematical expressions of the defrosting loss coefficient and outdoor ambient temperature and relative humidity to calculate the average defrosting loss coefficient of Kangding in the heating season as 0.15.Based on the measured data of the heating system and the performance analysis of the heat pump,this paper aims to improve the overall performance of the air source heat pump heating system,and proposes the "air source heat pump-hot water storage tank" heating system,and determines that the "outdoor temperature control is the main,storage Operational control strategy supplemented by hot water temperature and time control.Finally,this article uses Des T energy consumption simulation software to establish hourly load analysis models of the three functional buildings for the three functional buildings of Kangding City,"Class A residential,Class B residential,and office",and calculates and calculates the corresponding heating load.Characteristic analysis;based on the heating load characteristic analysis,this paper carried out the design of the air source heat pump direct heating system and the "air source heat pump-hot water storage tank" heating system;based on the "air source heat pump-hot water storage tank" heating system operation program The paper uses TRNSYS software to establish the air source heat pump direct heating system and the "air source heat pump-hot water storage tank" heating system simulation models,and carry out the analysis and determination of the best "critical outdoor temperature of heat storage and release".Comparison and optimization analysis of operating energy consumption and system energy efficiency.The calculation and analysis results show that: 1)Compared with the air source heat pump direct heating system,the "air source heat pump-hot water storage tank" heating system has better energy-saving effects in residential buildings(or buildings with continuous heating demand for 24 hours).The effect of energy saving in office buildings(or buildings that only require daytime winter heating)is not obvious;2)The “air source heat pumphot water storage tank” heating system adopts “outdoor temperature control as the main,and hot water temperature and time control as a supplement” According to the operation control strategy of Class A residential buildings,the best critical heat storage outdoor temperature is 6.12℃,and the best heat release critical outdoor temperature is 3.9℃.The heating system performance can be increased by 12.6%;in the B residential buildings,the best The critical outdoor temperature of heat storage is 8.38℃,and the critical outdoor temperature of best heat release is 2.13℃.The operating performance of the heating system can be improved by 15.7%;in office buildings,the critical outdoor temperature of heat storage is 6.19℃,and the forced heat release time is 14:00～ At 18:00,the operating performance of the heating system can be increased by 3.8%.Synthesizing the research results of this paper has important reference value and guiding significance for the design and operation control of air source heat pump heating system in Tibet. |
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