Research On Numerical Simulation Of Parallel Flow Condenser And Optimizing The Heat-transfer Capability Of Fin

The parallel flow condenser is a new type of heat exchanger which is pact andhigh-coefficient, this type heat exchanger has many advantages: high heat-transferefficiency、compactactness、less refrigerant charge、cheaper aluminum construction，it is one of the most promising heat exchangers in the future.This type of heat exchanger is applied in the field of automotive air conditioningfirstly, now it is gradually extended to the field of household air conditioning. This articleadopts the method of numerical simulation to study the parallel flow condenser, by themean of simulation, we obtain the thermophysical properties of condenser, we also raisesome methods to optimize the heat-transfer capability of air side.First, we should select the flow heat-transfer correlations of air side and refrigerantside, the correlations of refrigerant side contains three regions: superheat、two-phase andsubcooled; Secondly, we adopt the Finite Volume Method to divide the condenser intoseveral elements; Then, we use the heat transfer unit number in iteration to calculate exitparameters of each unit; Finally, we can obtain the heat-transfer performance of theoverall condenser.Then, comparation of the simulation results and experimental results verifies theveracity and the accuracy of the simulation model. According to the simulation model, wededuce the thermophysical properties of condenser under T1standard and T3standard.From the view of pass, it is concluded that1st and2nd pass occupy the main position inthe whole heat transfer, the combined heat of the two passes occupied more than60%ofthe total heat transfer; From the view of phase, the two-phase is the main force of heattransfer, two-phase heat transfer accounts for around65%of the total heat transfer. Finally,we research the heat transfer performance of air side, find that increasing air flowvelocity、decrease of fin spacing、 increasing the angle of louver and reducing the lengthof louver can improve the heat transfer performance of air side. This article gives the theory of heat-transfer of parallel flow condenser,the methodsof improving the whole heat-transfer performance, the guidance of design of parallel flowcondenser.