模拟加速方法的设计和验证

为在直升机旋翼气动性能数值模拟时简化建模过程、缩减计算时间，利用用户自定义函数（User Defined Function，UDF）设计混合模型盘激励模型和线激励模型，并对简单旋翼的悬停工况进行模拟.与风洞试验结果的对比表明：所设计的混合模型在简化旋翼模型的同时，能有效地计算旋翼的气动特性，模拟旋翼悬停时的流场，具有正确性和可行性；盘激励模型作为定常计算模型能够较快地计算得到旋翼的气动性能，缺点是不能体现每个桨叶对流场的单独作用；所设计的线激励模型在计算时由于所用的诱导速度为平均值，所以计算结果中旋翼效率比实际值偏高；通过与粒子图像测速（Particle Image Velocimetry，PIV）测量结果对比发现，线激励模型能较好地模拟出桨尖涡的分布.

Design and verification on CFD simulation acceleration method of helicopter rotor based on user defined function

To simplify the modeling process and reduce computation time during the numerical simulation of aerodynamic performance of helicopter rotor, the actuator disk model and the actuator line model of hybrid model are developed using User Defined Function(UDF) and a simple rotor in hovering is simulated. The results are compared with the results of wind tunnel test. It is indicated that, while the rotor model is simplified, these hybrid models are effective and feasible to calculate the aerodynamic characteristic of helicopter rotor in hovering and simulate the flow field; the actuator disk model is a steady solution model which is able to calculate the aerodynamic characteristic of rotor in a short time, but it cannot separately present the effect of every blade on the flow field; as the fact that an average induced velocity is used in the actuator line model, the calculated result of rotor efficiency is a little higher than the actual value; by the comparison between the hybrid model results and the Particle Image Velocimetry(PIV) measurement results, it was found that the actuator line model could well predict the distribution of blade tip vortex.