Exergetic Analysis And Optimization Research On The Combined Heating And Cooling System Of Hotel

As the country’s requirements for high-quality development continue to increase,people’s protection of green water and green hills continues to increase,and it also promotes the transformation of China’s energy use mode,and the proportion of clean energy applications represented by natural gas continues to increase.The triple supply system using natural gas as fuel has developed rapidly in China in recent years.This article selects the natural gas triple supply system of a commercial hotel as the research object,introduces the composition and configuration of the triple supply system,uses the Trnsys software to calculate the hotel’s cooling and heating load,electric load,and hot water load;and builds the math of the triple supply system The model analyzes the joint supply system,uses Trnsys software to build the physical model of the system,and analyzes and optimizes the impact of system operating parameters and operating strategies on the efficiency based on the experimental verification of the correct model.Finally,compared with the diesel triple supply system and the traditional central heating + electric cooling mode,a comparative analysis was made from three aspects: energy saving,environmental protection,and economy.The maximum cooling and heating loads of the hotel throughout the year are4420.4kW and 2870.2kW,respectively.The mathematical model of gas internal combustion engine and absorption refrigeration unit is established and analyzed,and the flow diagram is obtained.It is also analyzed that the loss of gas internal combustion engines in winter and summer operating conditions accounts for 38.5%and 34.1% of the combined supply system,respectively.In the lithium bromide absorption refrigeration system,the highest loss component is the high-pressure generator,Accounting for 60.4% of the total loss of the unit;followed by the absorber,accounting for 22.5% of the total loss of the refrigerator.Secondly,the relevant parameters that affect the efficiency of the combined supply system are analyzed,including the system load factor,the power generation efficiency of the gas internal combustion engine,the COP of the lithium bromide absorption refrigeration unit,the thermoelectric ratio,and the ambient temperature.At the operational strategy level,the operation mode of the combined supply system is The influence of electricity setting cold and heat and electricity setting by cold and heat on the system efficiency was also analyzed.According to the system parameters and operation mode,a method for optimizing the output of the system and improving the efficiency of the system is proposed.Compared with the energy supply method of the diesel triple supply system and the traditional central heating + electric refrigeration air conditioner,it is found that in winter and summer operation,the primary energy utilization rate and waste heat recovery rate of the natural gas-driven triple supply system are higher than the diesel-driven combined supply system..Compared with the diesel combined supply system and the traditional coal-fired boiler + electric refrigeration energy supply method,the three have more emission reductions and better environmental protection than the natural gas combined supply system;in terms of economy,the cost of the natural gas combined supply system is annual The value is 1.8 million yuan.The diesel combined supply system and coal-fired boiler + electric refrigeration and air conditioning are 3.936 million yuan and 2.85 million yuan,respectively.Significantly lower than the diesel combined supply system and coal-fired boiler +electric refrigeration air conditioning,the economic advantages are very obvious.