Research On Automotive Waste Heat Absorption Lithium Bromide Refrigeration System

The automobile air conditioner is the comfort security of modern automobile.However, most of cars are made up by compression type air conditioner, which runs will not only increase the energy consumption of the cars, but also have a big influence on overall dynamic performance. Aiming at above problems, a type of heat absorption lithium bromide refrigeration system is designed, which not only makes full use of the engine cooling water waste heat effectively, but also can save the fuel consumption so that reducing greatly the effect on dynamic performance by automobile air conditioning. The main work is as follows:Firstly, combing with the advantages and disadvantages of the traditional compression and absorption lithium bromide automobile air conditioner, a new kind of heat absorption lithium bromide refrigeration system is proposed to improve the current widespread use of compression automobile air conditioning refrigeration cycle. Through combining with the refrigeration of compression and absorption lithium bromide, not only makes full use of the engine cooling water waste heat effectively, but also overcomes the problem of low efficiency refrigeration of traditional absorption lithium bromide;Secondly, the thermodynamic calculation is made for this waste heat lithium bromide air conditioning system, mainly including the calculation of heat transfer area, medium flowing rate, etc; At the same time, the structure of key components such as generator, condenser and so on are designed. Through designing the generator,the waste heat was took full use by combining with the engine cooling water tank;through designing the condenser, it not only increases the cooling area, but also reduces the occupy area by replacing the single parallel flow heat exchanger with double parallel flow heat exchanger;Thirdly, the simulation of the air side of parallel flow heat exchanger is made.With referencing to the experimental value of pressure dropping and heat transfercoefficient, the influence on the heat transfer performance by the different wind speed.Through doing the orthogonal experiment, an structural parameters optimization of the parallel flow heat exchanger is made, which makes an conclusion that the better structural parameters combination is 25, that is, the spacing of the fin is equal to two millimeters, the length of fin is equal to 30 millimeters, the height of the fin is equal to 9 millimeters, the angle of shutters is equal to 25 degree.Fourthly, aiming at the designing of waste heat absorption lithium bromide refrigeration system, a simple experiment platform has been set up, which verifies the feasibility of the system. At the same time, according to comparing with the traditional compression refrigeration system, it can analyze that the system will decrease the power consumption obviously at the same refrigerating condition.