| Heat exchanger has the key role in the wind turbine gearbox lubrication systemoil temperature control. The oil temperature is increased step by step as the systemrunning; the poor cooling capacity of heat exchanger will quicken the oil oxidizationand lead to the wear or leakage to related components.The wind turbine gearbox lubrication system heat exchanger thermal design isvery importance. Meeting the required heat rejection and keeping the lowest runningcost are the key technology of its design.Plate-fin heat exchanger applies in the wind turbine gearbox lubrication systemdue to its compact structure and high heat transfer efficiency. The thermal design fromthe basic structure of hot and cold fluid channel in heat exchanger is studied in thisdissertation, the geometric surface characteristics of two design solutions arecalculated in this dissertation, the empirical correlation of heat transfer factor andfriction factor are used in heat rejection and pressure drop calculation, the feasibilityof heat transfer factor empirical correlation and not applicable of friction factorempirical correlation are verified by the wind tunnel test, the regression analysis isfinished by using the solver in Microsoft excel, the undetermined coefficient infriction factor empirical correlation is adjusted in this dissertation, the accuratefriction factor correlation of2.5MW wind turbine gearbox lubrication system heatexchanger has been gotten in this dissertation, the thermal check program of the twodesign solutions are corrected in this dissertation. the new method of judging the heatexchanger overall performance is proposed in this dissertation, the heat rejection andpressure drop of two design solutions are recalculated by using the corrected thermalcheck program, plate-fin geometric parameter as optimization variables, pressure dropetc. as constraint condition, heat transfer efficiency as optimization object, they areapplied in the better design solution corrected thermal check program, then the bestfin parameter combination is realized in the optimization design. And this method isused in production. |
