Study On Structure Design And Heat Transfer Performance Of The Corrugated Spiral Plate Heat Exchanger

Heat exchange equipment is one of the main means to realize energy utilization.The structure of the heat exchanger has an important influence on the heat transfer performance.The fluid motion direction of the ordinary spiral plate heat exchanger is parallel to the wall surface,and the heat transfer capacity can be further improved.There are a large number of fixed distance columns and spoiler columns welded between the heat transfer plates,and the stress concentration occurs at the welding position.Based on the advantages of the corrugated tube heat exchanger heat exchanger,a spiral plate heat exchanger with corrugated structure is designed according to the national and industry standards.By changing the structure and shape of the heat exchanger plate,the transition of the spiral plate heat exchanger from parallel to vertical flow is realized,the thickness of the boundary layer is compressed,and the heat transfer capacity is improved.The influence of corrugated plate structure on the heat transfer performance and resistance of spiral plate heat exchanger and the effect of corrugated structure on improving local stress were studied by numerical simulation.The comparative analysis of the numerical simulation results and the empirical formula summarized in the experiment shows that: according to the turbulence model,algorithm and boundary condition settings adopted in this paper,the maximum error between the simulation results and the experimental values is 3.72%,which can meet the engineering design requirements.Analyzing the numerical simulation results,when the Reynolds number is35839,the comprehensive evaluation coefficient of the corrugated spiral plate heat exchanger is 1.2 times that of the ordinary spiral plate heat exchanger,which is better than the ordinary spiral plate heat exchanger.The corrugation geometric parameters of wave distance L,wave height h and corrugation radius r were analyzed by the one-factor controlled variable method to study their effects on the performance of the spiral plate heat exchanger.The results show that when the Reynolds number is in the range of 12799～52000,the comprehensive performance of the corrugated spiral plate heat exchanger is better than that of the ordinary spiral plate heat exchanger,and when the Reynolds number is about 34000,the comprehensive evaluation coefficient of the heat exchanger reaches the maximum value.By comparing the comprehensive evaluation coefficients,these three groups of structural parameters are determined as the research objects,respectively,the wave distance L is 68 mm,75 mm and 125 mm,the wave height h is 3.5 mm,4.5 mm and 6.5 mm,and the corrugation radius r is 14.3 mm,17.5 mm and 40.0 mm.The three-factor and three-level orthogonal test method was used to compare the influence of the three factors on the comprehensive evaluation coefficient.When the Reynolds number is 33279,when the corrugation height is 3.5 mm,the corrugation pitch is 68.0 mm and the corrugation radius is 14.3 mm,the comprehensive performance is 1.494 times that of the ordinary spiral plate heat exchanger.Based on the Static Structural module in ANSYS to analyze the stress of the outermost heat exchange element of the corrugated spiral plate heat exchanger under optimal parameters,the results show that the stress at the distance column is reduced by 24.05%,which can improve the stress distribution state.The experimental results show that the greatest influence on the comprehensive performance is the corrugated plate wave height,followed by the wave distance,and the corrugated radius has the least influence.When the Reynolds number is 12799～63999,the wave height is processed dimensionlessly.The Levenberg-Marquardtde method is used to fit the criterion relation between Nusselt number and H/h.Compared with the general formula of design manual and the correlation su mmarized by experiment,the coefficient and index are the same order of magnitude,which verifies the rationality of the criterion relation.