Fuzzy Comprehensive Evaluation And Optimization Analysis For Natural Gas Driven Vuilleumier Cycle Heat Pump

Heating Ventilating and Air Conditioning energy consumption is the main energy consumption of buildings. Because COP of the electric drive is high, it becomes the main form of the building air conditioning. With the requirements of living environment increase, electric power consumption increase gradually and make the harmful for the ozone depletion and greenhouse effect. The natural gas as a clean energy can reverse environmental pollution rapidly. If combine the natural gas and the heat pump to reduce ozone depletion and alleviate global warming will have the important meaning. Therefore this paper does fuzzy comprehensive evaluation and optimization analysis for natural gas driven Vuilleumier cycle heat pump. To achieve the purpose of heating and refrigeration, the natural gas driven Vuilleumier cycle heat pump use the flue gas heat to heat the high temperature cavity and use the natural medium to complete the cycle. Taking a villa in Beijing as object, based on the load calculation and combined with experience formula to design the structural type for all components of the VM cycle heat pump.The heat source temperature, room temperature heat source and low temperature heat source are950K,328K and273K respectively. The ideal VM cycle heat pump COP is3.25. If we consider the shuttle loss, pumping loss, regenerator loss, flow resistance losses and other losses, the actual VM cycle heat pump COP is1.93. And the proportion of the regenerator loss is the largest in all kinds of the energy losses. To improve the performance of the cycle, the finite time thermodynamic analysis of quantization VM cycle shows that:should adopt the big frequency ratio gas as the medium.And for this system, adopting the fuzzy comprehensive evaluation of performance of the natural gas driven VM cycle heat pump has been discussed from five aspects: technology, economy, safety, maintainability and environmental protection. Obtains following conclusion:its environmental protection outstanding, the safety and maintainability are better, technology is medium level, but economy is bad. To optimize the system, we explore the solar energy and biomass energy as the drive and heat exchanger structure parameters and working medium to the influence of the cycle.