Design Optimization Of β-type Stirling Free Piston Booster Pump

At present,for the reverse osmosis water desalination project in China,the pumps used mostly depend on imports and need to consume a lot of electricity,which increases the cost of water desalination.At the same time,this kind of pump has the problems of complex structure,large volume and large noise.In order to solve the above problems,this paper proposes and designs a new booster pump structure for reverse osmosis desalination,and analyzes its working characteristics.First of all,this paper describes the principle of reverse osmosis desalination in detail.After understanding the specific working environment and principle of booster pump,the structural schematic diagram of new booster pump is designed.The new structure adopts the coupling form of Stirling free piston engine and reciprocating piston pump to obtain Stirling free piston booster pump.Secondly,the design and calculation of Stirling free piston engine are carried out according to the initial rated power and drainage pressure.The structural design and calculation of Stirling type free piston are used as the prototype to obtain the structural dimensions and parameters of scavenge volume,heater,regenerator,cooler,distribution piston and power piston.The thermodynamic model of Stirling free piston booster pump power system is established by using practical isothermal model.The results of volume change,pressure change,output power and efficiency of each cavity in the power system are obtained,and the influencing factors of power and efficiency are studied.Thirdly,according to Navier Stokes equation,Euler equation and Bernoulli equation,the output system of Stirling free piston booster pump is modeled,and the results of liquid flow rate,flow rate,pressure,power and efficiency in the process of suction and drainage are obtained.The comparison results show that all parameters meet the requirements of expected values.Finally,genetic algorithm is used to optimize the parameters of the power system of Stirling free piston booster pump,taking the output power as the optimization objective.The results show that the output power is significantly increased by optimizing the four cycle parameters of temperature ratio,scavenging volume ratio,useless volume ratio and piston phase angle.In order to reduce the instantaneous pulsation,the output structure of three cylinder pump and the optimization method of connection and arrangement of Stirling free piston engine are used to reduce the pulsation.The analysis results show that the flow pulsation is greatly reduced.