Simulation Study On The Heat Transfer And Flow Resistance Characteristics Of Intercooler With Compact Construction

The ribbon-tubular air-to-air intercooler has been widely used in many kinds of vehiclesand engineering machinery for its compact construction and high efficiency, which hasprogressed rapidly in recent years. Due to the influence of offset strip fin inside the tube, thedisturbance of fluid is enhanced effectively, the thermal boundary layer is destroyed, and theeffect of heat transfer is improved effectively. The heat transfer and flow resistancecharacteristics of intercooler were influenced by the fin pitch, height and length of offset stripfin.In this paper, a hot air channel unit model with offset fins inner the tube was built basedon experimental data by combination of test and numerical calculation. By keeping thetemperature of cooled-wall and the air in the hot air channel unchanged, making air mass flowrate in the hot air channel and the thickness of the fin constant remain stable, numericalmodels with different structures were simulated by using FLUENT software. The modelswere established by using different parameters of the offset strip fin pitch, height, and length.Streamline and domains distributions of temperature, pressure, velocity vectors, curves of theheat transfer factor and the friction-factor changing with structural parameters were obtained.According to simulation results, the influence of the fin pitch, height and length on the heattransfer and flow resistance performance of the intercooler were analyzed.The heat transfer factor j and friction factor f decreases with increase of the fin pitch,height and length for different mechanisms. The primary aim of changing fin pitch is tochange the effective heat transfer area per unit of volume, and further change the heat transferand flow resistance performance of the fin. Adjusting the parameters of the fin height is tochange the intercooler core flow cross section, the effective heat transfer area per unit ofvolume and the velocity of the fluid, which further change heat transfer and flow resistancefin performance. The number of incision and the shape can be changed by adjusting the lengthof incision, which also change the fin performance of heat transfer and flow resistance. Thevelocity field, temperature field and pressure field is affected by the length less than the finpitch and height. The simulation of the flow field based on experimental data showed that elative error ofthe heat transfer factor j and friction factor f were5.16%~5.29%and2.90%~2.98%. Theheat transfer and flow resistance characteristics of intercooler can be well described byComputational Fluid Dynamics Method.Comprehensive performance of models with different geometry parameters werecompared by Performance Evaluation Criteria and the best model Parameter isS=7mm, H=9mm, l=8mm.