Applied Research On Genetic Algorithm To The Structure Optimization Desihn Of Adjustable Steam Compressor

It’s well known that paper industry is one of the greatest energyguzzlers.The greatest potential of energy saving lies in the drying section. Steamcompressor can increase steam pressure without using the mechanical energydirectly. Because of such advantage, the ejector is widely applied in the dryingsection of paper machine to reduce the energy consumption and has a significantenergy saving effect. Energy-saving effect of the steam compressor can bemeasured by the size of the jet coefficient. So the design of adjustable steamcompressor structure and steam compressor system plays a key role for theperformance of the steam compressor. For a long time, however, the design ofsteam compressor is based on the experience and its optimized design is rarelystudied. This paper tries to use the advantages of genetic algorithm incombinatorial optimization to optimize the structure size of the adjustable steamcompressor design and verify the rationality of the design of genetic algorithmoptimization in computational fluid dynamics software simulation. Finally, theadjustable steam compressor has been applied in the industrial field to testwhether the optimization design is reasonable or not again. The main contents ofthis paper are as follows:(1) Determination of optimization goal. Firstly, the adjustable steamcompressor coefficient models are established by the using of the empiricalformula method, gas dynamic function method and thermodynamic method. Thecharacteristics of the three models are compared. It is concluded that the size ofthe injection coefficient and the key size of the values are closely related. Theother size of the adjustable steam compressor is on the basis of the critical sizedesign. Then establish the relation between adjustable steam compressorperformance injection coefficient and critical dimensions.The other sizes ofadjustable steam compressor are designed based on the basis of the key size.Structure optimization of key size can optimize the steam compressor. (2) Attainment of the best similar geometric parameters is based on geneticalgorithm. Firstly, the principle of genetic algorithm and implementation stepsare introduced；then the parameters and the optimization of conditions of geneticalgorithm are analyzed and set. Through genetic operations of selection,crossover, mutation, it can make a chromosome function to maximum, genecombination of the chromosome is the best similar geometric parameters.(3) Verification of rationality of the genetic algorithm optimization’s resultsbased on CFD simulation software. In this part，the simulation model is built byusing geometric parameters of steam compressor obtained by genetic algorithm,The internal flow pattern of steam compressor can be observed more intuitivelythrough the simulation. Analyse the way to mix and to lose energy in theadjustable steam compressor, and compare the efficiency of adjustable steamcompressor in different conditions.(4) The new steam compressor system design and engineering practice. Thesegment focus on analysis of traditional way of three sections of steam supplydeficiency and point out the advantages and disadvantages of existing steamcompressor system to put forward a kind of steam compressor system remouldmode based on the three sections of gas supply. The new type of steamcompressor system is an economic reform scheme for small and medium sizedpaper industry to achieve the purpose of energy saving. The final purpose of anydesign is to serve the practice, the steam compressor optimized by geneticalgorithm is used in this system, and it can achieve the purpose of energy saving.Once again proves that the correctness and rationality of using genetic algorithmto optimize the structure of adjustable steam compressor.