Multi-objective Optimization Of Spiral Plate Heat Exchanger Based On Flow And Heat Transfer Characteristics

The heat exchanger is widely used in many fields,and the proportion of design and construction cost is relatively large.The optimal design of the heat exchanger can improve the performance while reducing the cost.This kind of research has a very important meaning in the practical application of the project.Spiral plate heat exchangers also have a wide range of uses in production,but pepole are more likely to rely on experience in optimization design which is not extensive and in-depth in theoretical research,and it’s often unable to meet specific needs or can not meet more design requirements,so in practice,most of the enterprises more likely to make the application of mature technology,the design method is relatively perfect plate fin heat exchanger and shell and tube heat exchanger.In order to improve the shortcomings of the spiral plate heat exchanger in the optimization design,this paper uses the minimum entropy production principle,based on the genetic algorithm to finish its multi-objective optimization.In the optimization of the spiral plate heat exchanger,the first consideration is the problem of the objective function.The selection of the objective function is very important for the optimization and the applicability of the result.This paper chooses the dimensionless entropy output as the objective function.The geometrical parameters of the heat exchanger are the design variables.The heat transfer capacity and the allowable pressure drop and the heat exchanger design standard are the constraint condition.These conditions are the limiting factors of the whole optimization design of the heat exchanger.In this paper,the entropy production caused by the pressure drop and the entropy produced by heat transfer are the objective function.The entropy production caused the pressure drop and the heat transfer entropy are described in this paper.The two objective functions are used as the multiobjective function.The results show that,whether the flow entropy is a single target optimization or a temperature entropy production,the results show that the flow entropy and the heat entropy production are the single target.The optimization of the target,the heat transfer area and the pressure drop are larger than those of the multi-objective optimization results,and the cost of the construction and the operating cost are higher than the multi-objective optimization results.In order to study the actual operation effect of the spiral plate heat exchanger designed by multi-objective optimization design and to study the parameters of the performance of the spiral plate heat exchanger,this paper establishes the mathematical model of flow and heat transfer inside the spiral plate heat exchanger.The distribution of the pressure field and the variation of the temperature field are mainly studied.The results are also obtained by numerical simulation.The heat transfer performance of the heat exchanger is studied by using the fluent simulation.Finally,the fluid flow in the internal flow path of the heat exchanger is obtained.The flow velocity of the hot and cold fluid in the furnace,the flow direction and the heat exchanger structure parameters on the performance of the heat exchanger.The simulation results directly reflect the relationship between the relevant design parameters and the operating parameters and the performance of the heat exchanger.And optimization played a very good guiding role.