Numerical Simulation And Experimental Research Of Hydrodynamics And Thermal Characteristics Of Chevron-Type Plate Heat Exchangers

Using the numerical simulation based on simplified model, it was difficult to predict hydrodynamics and thermal characteristics of plate heat exchanger accurately. Therefore, a model of the accurate size of actual chevron-type plate heat exchanger geometry was built in this paper, including distribution area and heat exchange area, with two channels for hot and cold water respectively. Using computational fluid dynamics software FLUENT6.3, the pressure drop and heat transfer coefficient for cross-corrugated plate heat exchangers at four different inlet velocities were investigated. The major jobs are listed below:1. The pressure drop and temperature difference between the inlet and outlet were compared with the experimental data, which shows an error within 6%. By numerical simulation, the hydrodynamics and thermal characteristics of chevron-type plate heat exchangers(PHEs) properly were predicted and this method can be used for physical performance test of PHEs, which is of some practical significance.2. The flow pattern in two channels was described in detail. It shows that the flow nonuniformity in distribution area of inlet and outlet has significant influence on the fluid distribution in heat exchange area. 12 test sections in the cold flow channel were cut off to test their velocity and temperature, it showed that volumetric flow rate and absorbed heat of the inlet and outlet side were larger than those of the other side, the influence of distribution area on fluid distribution in the channel mainly occurred in the connection of the distribution area and heat exchange area. Compared with flow uniformity, flow nonuniformity in the channel leads to heat transfer coefficient reduction notably and pressure drop increase. The conclusions of this paper are of some significance in the optimum design of plate heat exchangers.3. The law of corrugation inclination angleβinfluence on fluid pattern was studied, the flow pattern in channels changed from cross flow to zig-zag flow with angle increasing. The flow pattern of cross flow and zig-zag flow was described in detail.4. By experimental methods, the flow pattern in the channel was studied comprehensively. The simulation result of fluid distribution and zig-zag flow was proved accurately.