为综合优化离心泵作透平的水力和声学性能,建立了一种基于响应面的离心泵作透平水力和声学性能多目标优化方法。首先在对比分析叶轮几何参数对透平水力和噪声影响的基础上,根据敏感度筛选出对噪声影响显著的关键参数;进而应用响应面方法构造显著变量与多目标函数的响应面多元回归模型,分析影响水力效率与噪声的参数间交互作用;最终以水力效率不降低和总声压级最小为响应目标,兼顾性能与噪声确定最优参数组合,即叶片进口安放角为19.5°,叶片出口安放角为20°,叶片出口宽度为16 mm,叶片包角为92°,叶轮进口直径为101 mm,叶片数为12。对某离心泵作透平多目标优化结果表明,叶轮进口直径、叶片出口宽度、叶片数及叶片包角对内场噪声总声压级影响显著;响应面模型能够反映参数与响应值之间的相关性;经试验验证优化后透平水力效率平均提高了1.98个百分点,总声压级降低了4.95 d BA,表明采用的响应面法能够在不影响透平原有水力性能的前提下改善声学性能。
As a way of energy saving by recovery of residual pressure, centrifugal pump as turbine(PAT) has been widely used in many fields. As PAT is gradually developed for high power, flow-induced noise becomes one of the most important issues that cause negative effect on reliability. In order to improve both hydraulic and acoustic performances of PAT, an optimization method combining sensitivity analysis and response surface was established. Firstly, through comparison of impeller parameter impact on hydraulic and noise performances, the geometric parameters with great influence on acoustic were filtered based on sensitivity analysis. Further more, with the efficiency and A-weighted overall sound pressure level(OASPL) as target, the multiple regression models connecting variables and multi-objective functions were constructed. Optimization for high efficiency and low OASPL of PAT was carried out with the focused research on the interaction among key parameters. During the investigations, a synchronous acquisition of hydraulic parameters and noise signals were realized on the basis of INV3020 C data acquisition system and hydraulic test system in an open test loop. The liquid was pressurized through booster pump, and then impacted the turbine's impeller to make it rotate. The dynamometer consumed and measured the turbine's energy. The operating condition was adjusted by regulating the converter's frequency to change the booster pump's capacity. The flow-induced noise signals were collected using hydrophone at a sampling frequency of 25,600 Hz. The signals were amplified and recorded by INV3020 C data acquisition system, and Fast Fourier Transform was used to compute the spectra with the Hanning window for reducing the spectrum leakage. The hydraulic performance(such as head, shaft power and hydraulic efficiency) was calculated. The unsteady numerical simulation was performed to obtain noise-generating fluid forces using k-ε turbulence model. After that, a time series of pressure fluctuations at flui