高负荷吸附式压气机叶型的优化设计

发布时间：2018-03-07 18:44

本文选题：高负荷　切入点：吸附式　出处：《南京航空航天大学》2012年硕士论文　论文类型：学位论文

【摘要】：在实验室已有的无吸气叶型优化设计平台基础上，用吸力面的一段曲线模拟吸气槽，且在亚音速情况下，吸气边界给定均匀的流量通量分布，实现了吸附式压气机叶型优化设计平台。该优化平台基于数值最优化和流场正问题计算相结合的方法，优化策略采用遗传算法，叶栅流场计算采用实验室自编的CFD程序，叶型参数化采用基于修改量的方法。应用此吸附式压气机叶型优化设计平台进行了两个优化：优化算例1是为了验证附面层吸气能够提高扩散因子的说法，该优化以某大弯角高亚音叶型为初始叶型，以扩散因子和总压损失系数为设计目标，最终获得了吸气系数为0.01时扩散因子达到0.676、总压损失系数为0.0195的叶型，与优化前相比，优化后的扩散因子保持不变，总压损失系数下降了54%。与常规叶型相比，该优化叶型压力面尾部出现拐点，拐点前流动加速减压，缺点是降低了气流转角和叶型尾部负荷，但也减小了流动分离，降低了流动损失。优化算例2是为了验证此优化平台进行叶型设计的可行性，该优化以上一优化的初始叶型为初始叶型，以总压损失系数、静压比和总压比为设计目标，最终获得了可以满足指定进出口条件的叶型。以优化算例1获得的高负荷吸附式压气机叶型为研究对象，通过数值方法进一步研究了吸气参数对叶栅性能的影响规律，研究发现：对于该叶型，，吸气槽角度会影响所需的吸气量，吸气槽角度越大，获得同样的叶栅性能所需的吸气量越小；对于该叶型，采用简化的吸气模型能够获得与90度吸气槽角度的吸气槽模型相近的计算结果；对吸气量的研究获得了与现有文献一致的结论，存在一个最佳的吸气量，随着吸气量的增加吸气效果减弱，当吸气量大于最佳吸气量时，叶栅性能基本不变；对于该叶型，当吸气参数接近设计值时，叶栅性能对吸气宽度和吸气位置的扰动不敏感。
[Abstract]:On the basis of the optimized design platform of non-suction blade shape in laboratory, a curve of suction surface is used to simulate the suction trough, and under the condition of subsonic velocity, the uniform flux distribution is given at the suction boundary. The optimal design platform of adsorption compressor blade is realized. The optimization platform is based on the combination of numerical optimization and flow field forward problem calculation. The optimization strategy is genetic algorithm, and the cascade flow field calculation is based on the CFD program compiled by the laboratory. Leaf shape parameterization is based on modification method. Two optimizations have been carried out by using this optimal design platform for the blade shape of adsorption compressor. The optimization example 1 is to verify that the boundary layer suction can improve the diffusion factor. The optimization takes a large angle high subtone blade shape as the initial blade shape. With diffusion factor and total pressure loss coefficient as the design goal, the blade shape with diffusion factor of 0.676 and total pressure loss coefficient of 0.0195 when the inspiratory coefficient is 0.01 is obtained. Compared with before optimization, the optimized diffusion factor remains unchanged. The coefficient of total pressure loss is reduced by 54. Compared with the conventional blade shape, the pressure surface of the optimized blade has an inflection point at the end of the pressure surface, and the flow accelerates and decompresses before the inflection point. The disadvantage is that the air flow angle and the tail load of the blade shape are reduced, but the flow separation is also reduced. The flow loss is reduced. The optimization example 2 is to verify the feasibility of the optimization platform for blade shape design. The optimization of the initial blade shape of the above optimization is the initial blade shape, with the total pressure loss coefficient, the static pressure ratio and the total pressure ratio as the design objectives. Finally, the leaf shape which can satisfy the specified import and export conditions is obtained. Taking the blade shape of high load adsorption compressor obtained from optimization example 1 as the object of study, the influence of suction parameters on cascade performance is further studied by numerical method. The greater the suction groove angle, the smaller the suction required to obtain the same cascade performance; for the blade, The simplified suction model can obtain the calculation results similar to that of the 90 degree suction groove model, and the results of the study on the suction volume are in agreement with the existing literature, and there is an optimal inspiratory capacity. With the increase of inspiratory capacity, the suction effect weakens, and the cascade performance is basically unchanged when the inspiratory capacity is larger than the optimal suction rate, and for the blade shape, when the suction parameters are close to the design value, the cascade performance is not sensitive to the disturbance of the suction width and the suction position.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH45

【相似文献】