Composite Corrugated Plate Heat Exchanger, Heat Transfer And Pressure

As a thermal power mechanical apparatus, plate heat exchangers have been widely used in the fields of energy transport processes for its perfect performance. The deeper researches on plate heat exchanger are necessary for enlarging its range of application. Compared with tube and shell heat exchangers, plate heat exchangers have such advantages as high effectiveness, compactness and easy cleaned, also have disadvantages, such as low allowable sustaining pressure and big pressure drop. Aiming at the primary disadvantage of big pressure drop that exists in traditional chevron-type plate heat exchangers, compound corrugation plate heat exchangers are proposed.First of all, the compound corrugation plate with geometry parameter comprised of corrugation inclination angel 45 °, the transversal corrugation space 30 mm , the transversal corrugation height 1.5mm, the longitudinal corrugation space 16mm and the longitudinal corrugation height 1.5 mm was selected to establish physical model consistent with experimental condition. Unstructured grid, laminar flow or RNG k- ε turbulence model were used in numerical calculation. Three-dimensional velocity field of compound corrugation plate heat exchangers, the heat transfer criterion equation and friction coefficient relation in different Renault number scopes. In order to confirm the accuracy of results from numerical calculation, water -water and the water - oil heat transfer stage were establish and the heat transfer experiment of water -water and the water - oil were carried out. Through the contrast, we discovered that the results from numerical calculation and experiment approach and the change of Nu number is consistent with that of Re number. The approach illuminates that it is a feasible way to investigate the performance of compound corrugation plate heat exchanger by numerical calculation.In order to investigate heat transfer and flow resistance of compound corrugation plate further, compound corrugation plate of every geometry parameters in range of corrugation inclination angel from 15° to 75°, the transversal corrugation space from 16mm to 50 mm , the transversal corrugation height from 0.5 mm to 2.5 mm, the longitudinal corrugation space from 8mm to 32mm and the longitudinal corrugation height from 0.5 mm to 2.5 mm is chosen to be calculated by numerical calculation. Finally the law that geometry parameters of compound corrugation plate influence heat transfer and flow resistance is obtained. It is as follows: with increasing of corrugation inclination angel β, both heat transfer rate and flow resistance increase as well, but integrated performance of plate heat exchangers displays better with a smaller corrugation inclination angel β; the change of transversal corrugation height has some certain influence on heat transfer but nearly no influence on flow resistance; the change of transversal corrugation space has tiny influence on heat transfer, but too big or too small transversal corrugation space will lead to a bigger friction coefficient; the reduce of longitudinal corrugation space will strength heat transfer in a certain extent and synchronously augment friction coefficient; the change of longitudinal corrugation height obviously influences both heat transfer and augment friction coefficient. Through plentiful numerical calculation, that corrugation inclination angel, longitudinal corrugation space and longitudinal corrugation height have a remarkable influence on both heat transfer and friction coefficient are discovered. After summarizing these major factors, the heat transfer criterion equation and friction coefficient equation in the Reynolds number range 2000 < Re < 20000 for compound corrugation plate heat exchangers are obtained.friction coefficient equation is .Theachievement of comprehensive criterion relations can provide instructional advice to design of compound corrugation plate heat exchangers.