Study On The Heat Transfer Performance Of High Temperature Air For Flue Gas Waste Heat Recovery

The arrival of twenty-first Century makes China’s rapid industrial development, the increase in the demand for substantial energy, therefore improve the energy utilization ratio is very important. High temperature air heat exchanger is an important equipment for improving the thermal efficiency of industrial furnaces, heat exchanger for air exhaust temperature is too high, the low rate of utilization of residual heat from flue gas. By the methods of theory combined with numerical simulation, the air flow and heat transfer of flue gas in the heat exchanger optimization are studied in order to give full play to the role of heat transfer surface, improve the efficiency of heat transfer.The heat exchanger on the establishment of heat pipe air flow field model, based on the actual operating parameters as boundary conditions, through the ANSYS CFX software on the heat pipe flow model and simulate heat transfer characteristics of it. Through the simulated data are compared with the actual parameters, found in good agreement with the actual operating data, the calculation model of heat exchanger simulation results heat exchanger for the prediction of the heat transfer performance is relatively good accuracy and feasibility, simultaneously has also analyzed some causes of errors between the simulation results and the actual data..Through the method of enhancing heat transfer of tube heat exchanger improved scheme is put forward, that is adding circular fin on the outer wall of light pipe to increase the heat transfer area of the heat exchange tube to heat transfer efficiency of heat exchanger. Based on the numerical simulation of fin thickness, fin pitch, fin height, the flue gas inlet velocity and other parameters. The influence on heat transfer performance of the gas inlet velocity than the influence of structural parameters of finned tube on it.Changing the structure parameters of gas inlet velocity and finned tube, through simulation comparison of each parameter, the influence of each parameter on heat transfer effect. As a result, when the flue gas fin thickness is0.8mm, fin pitch of3mm, fin height is12.5mm, inlet velocity is5.16m/s optimal heat transfer effect.