Design And Operation Optimization Of Multi-source Complementary Heating System Based On Air Source Heat Pump In Tibetan Area Of Western Sichuan

Tibetan area of western Sichuan is a cold and cold area with building heating needs,but the area has not been classified as a building heating area for a long time,and there is a lack of optimal design and operation methods that can be used to guide the heating of local residential buildings.Restricted by the economic development level of the Tibetan area of western Sichuan,restricted by topography and terrain in the Hengduan Mountains,high mountains and deep valleys,the traditional central heating technology is difficult to apply,resulting in the heating problem in the region has not been effectively resolved.The Tibetan area of western Sichuan has abundant water energy resources and abundant hydropower.It is suitable for the use of electric heat pumps as the heat source for heat supply.Combining local geography,weather,resources and other factors,the air source heat pump is a feasible way to solve the heating problem in the Tibetan area of western Sichuan.Air source heat pump heating is currently the main application form of clean heating in rural areas.The unit has high energy efficiency and a wide range of equipment capacity.It is suitable for large,medium and small scale heating systems.However,the system is unstable when the air source heat pump is operated alone.Combined with the abundant renewable energy resources such as solar energy,biomass energy and geothermal energy in the Tibetan area of western Sichuan,the establishment of a multi-source complementary heating system mainly based on air source heat pumps and assisted by a variety of renewable energy sources can improve the stability and energy efficiency of the system,Economy and environmental protection,is an effective way to solve the problem of heating in the region.Due to the complex terrain and volatile climate in the Tibetan area of western Sichuan,there are few meteorological parameters available in the local area,and regional division is needed to support the design of multi-source complementary heating system based on air source heat pumps（MSCHS-ASHP）in various regions.The selection of the heat source type of the MSCHS-ASHP,the matching of equipment capacity and the setting of operating parameters directly determine whether the system is economically feasible.At this stage,the Tibetan area of western Sichuan urgently needs a set of optimized design and operation methods suitable for the heating of local residential buildings.In order to solve the above problems,this study divides the building heating climate zone in Tibetan area of western Sichuan,and establishes and solves the optimization model of the energy form,equipment capacity and operating parameters of the MSCHS-ASHP.The recommended design indexes and system performance parameters of each building climate zone were obtained.The specific work content is as follows:First,combined with the heating demand of Tibetan area of western Sichuan,using weather data files,the HDD15 of 66 cities in and around Tibetan area of western Sichuan was calculated,which was used as the classification index of k-means clustering algorithm to divide Tibetan area of western Sichuan into four Building heating climate zones,and obtained the zoning map of residential building heating climate zone in Tibetan area of western Sichuan on the ArcGIS platform.Secondly,the heating model of the air source heat pump multi-source complementary heating system was compiled on the MATLAB platform,with the system life cycle cost（LCC）as the objective,and the cuckoo optimization algorithm was used to perform the model under the condition that the service life was 15 years.Optimized the solution,obtained the best energy form,equipment capacity and operating parameters of the heating system of the typical two-story buildings in rural areas,the four-story buildings in towns and the ten-story buildings in urban areas in the four zones of the building heating climate zone.The recommended design index for the rated input power of the unit air source heat pump in the heating climate zone of each building is obtained.The results show that for rural,township and urban residential buildings,the heat sources in the air source heat pump multi-source complementary heating system have good matching and good system stability.Finally,using the coal-fired boilers heating system（CBHS）as a comparison,we established the life cycle cost（LCC）,seasonal energy coefficient（SCOP）,operating cycle equivalent CO₂ emissions（CO₂-eq）and cumulative power consumption during heating season(W_ele)as an evaluation index evaluation system,and analyzed the performance of the MSCHS-ASHP.The results show that except for the economics of the MSCHS-ASHP in each building type in the areaⅠand the CBHS are almost the same,the economic,energy efficiency and environmental protection benefits are The MSCHS-ASHP is superior to the CBHS.In terms of cumulative power consumption during the heating season of the system,rural buildings are the largest,all of which are higher than 30kWh/（m²·a）except Zone I,with the highest value appearing in Zone IV,reaching 87.53kWh/（m²·a）;urban Buildings are second,of which only the average power consumption in the heating seasons in zones III and IV is greater than 15 kWh/（m²·a）;the townships have the smallest buildings,and the cumulative power consumption in the heating seasons in zones I,II,and III are less than 15 kWh/（m²·a）.The use of a MSCHS-ASHP in the Tibetan area of western Sichuan can greatly improve the heating stability of the system and ensure the stability of the indoor temperature.This study proposes an optimized design method for the MSCHS-ASHP.This method can realize the economical design and operation of the system,and can improve the heating stability,energy efficiency and environmental protection of the system.Provide a set of optimized design and operation methods for the heating of residential buildings in the Tibetan area of western Sichuan,and provide new ideas for solving local heating problems.