Performance Check Of Offset Fin Heat Exchanger

Plate-fin heat exchangers due to compact,high heat transfer efficiency,has been widely used in petrochemical,energy,power,metallurgy,refrigeration and other industries.Plate-fin heat exchanger performance depends on heat transfer and flow characteristics of the fin surface.Dislocation fins are called high performance fin,commonly used to enhance heat transfer applications.Hot and cold heat transfer fluid rely mainly on the fins complete.Heat transfer and flow characteristics of the fin surface is usually expressed by the heat factor j and friction factor f.Therefore,to accurately grasp the heat transfer and flow characteristics of the fin surface is basic research plate-fin heat exchanger performance.In this paper,heat transfer factor and friction factor calculation methods in the literature were reviewed and summarized.Then verified the five kinds of heat transfer and friction factor formula applicability on the condition of gas and liquid experimental data.The results showed that the experimental data to the working fluid is gas obtained by the calculation formula does not apply to the working fluid is liquid friction factor and heat transfer fin factor.Same to the experimental data to the working fluid is liquid obtained by the calculation formula.On this basis,the establishment of a working fluid for the calculation model of gases and liquids under conditions of heat transfer factor and friction factor by reference.Selection of the least squares method,genetic algorithm and quasi-Newton method in the model coefficients were fitted.The results show that the accuracy of the least square method is best when fitted to the dislocation of heat transfer factor and friction factor.Fitting calculation formula to predict the working fluid is gas,the maximum error of heat transfer factor of new18.21%,the average error was 12.46%,the maximum error of the friction factor of 18.03%,with an average error of 9.44%.Prediction working fluid is liquid,the maximum error of heat transfer factor of new 18.92%,with an average error of 6.24%,the maximum error of the friction factor of 13.51%,the average error is 4.7%.Through the study of the heat exchanger method of checking,fitting formula of heat transfer factor and friction factor based on a mathematical model of dislocation check the plate heat exchanger fin.Then using C ++ language,developed the program interface,and the preparation of the verification software.Selection of experimental data in the literature,tocheck the accuracy of the software under different working fluids were verified.The results show that school-core software can be used under various conditions,both hot and cold sides of the fluid displacement performance computing plate heat exchanger fins and checking software when checking the performance of the heat exchanger,the maximum outlet temperature error of 9.48%,the maximum error is 9.59% drop.The project meets the requirements for the heat exchanger...