针对目前汽车气候老化研究仍处于耗时长、成本高、操作难度大的试验阶段，在时间和空间上都是离散的试验数据，无法全面、准确地描述汽车整车或零部件的抗老化性能的问题，提出了一种汽车气候老化的数值研究方法。基于汽车整车气候老化试验，在考虑了自然环境因素(如太阳辐射、水分、气温、风速等)，车内热辐射的多次反射和车内空气吸热、传热的影响的条件下，建立了自然曝晒下汽车内外表面的传热模型，并进行仿真和测试，仿真结果与测试数据基本一致。仿真和测试的结果，得到了车身外表面温度分布和传热特性及其主要影响因素，对比了热辐射、热对流和热传导3种传热方式的强度和总传热量，确定了零部件表面温度场中局部高温点、低温点的位置。该数值方法和仿真模型可用于预测和评估各种典型气候下汽车的耐候性。%In view of the problem that the current researches on vehicle weathering aging is still at an ex-perimental stage with the features of time consuming, high cost and difficult operation, and test data, being discrete in both time and space domains, cannot thoroughly and accurately describe the aging resistance performance of vehi-cle and its components, a numerical research method for vehicle weathering aging is proposed. Based on vehicle weathering aging test and under a condition of considering the effects of natural environmental factors ( solar radia-tion, humility, air temperature and wind velocity) and the multiple reflection of heat radiation and air heat absorp-tion and transfer within the vehicle, a heat transfer model for both interior and exterior surfaces of vehicle under the natural exposure to the sun is built, and both simulation and test are conducted with the results coincide to each oth-er. As a result, the temperature distribution and heat transfer characteristics of the exterior surfaces of vehicle body and their main influencing factors are obtained; the intensities and total amounts of three modes of heat transfer ( heat radiation, heat convection and heat conduction) are compared;and the positions of local high and low tem-perature points in the surface temperature field of components are located. The numerical method proposed and sim-ulation model built can be used for predicting and evaluating the weather resistance of vehicles under various typical weathers.
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