梁蕴致, 龙云, 龙新平, 等. 文丘里管内空化流动大涡模拟的验证与确认[J]. 中国舰船研究, 2022, 17(3): 196–204. doi: 10.19693/j.issn.1673-3185.02607
引用本文: 梁蕴致, 龙云, 龙新平, 等. 文丘里管内空化流动大涡模拟的验证与确认[J]. 中国舰船研究, 2022, 17(3): 196–204. doi: 10.19693/j.issn.1673-3185.02607
LIANG Y Z, LONG Y, LONG X P, et al. Verification and validation of large eddy simulation of cavitating flow in Venturi[J]. Chinese Journal of Ship Research, 2022, 17(3): 196–204. doi: 10.19693/j.issn.1673-3185.02607
Citation: LIANG Y Z, LONG Y, LONG X P, et al. Verification and validation of large eddy simulation of cavitating flow in Venturi[J]. Chinese Journal of Ship Research, 2022, 17(3): 196–204. doi: 10.19693/j.issn.1673-3185.02607

文丘里管内空化流动大涡模拟的验证与确认

Verification and validation of large eddy simulation of cavitating flow in Venturi

  • 摘要:
      目的  旨在定量分析验证与确认(V&V)方法对有限空间内部空化流动求解的准确度描述的适应性,对文丘里管内不同空化数下的流动进行大涡模拟(LES),用以实施V&V方法,并扩展该方法的应用范围。
      方法  首先,采用大涡模拟结合Zwart-Gerber-Belamri (ZGB)空化模型对不同空化数下文丘里管内部的流动进行数值模拟;然后,采用基于五方程的V&V方法,计算不同工况下进出口压力比和各监测点压力系数的准确度阶数及数值基准值;最后,计算大涡模拟的验证不确定度,以及与模拟值和试验结果的对比误差进行比较,完成确认过程。
      结果  结果表明,在3种空化数下,进出口压力比这一全局量的验证不确定度均较低,且均实现了对应不确定度水平下的确认。除空化数σ=0.263时x/Dth=9及x/Dth=13监测点处压力系数的验证不确定度较高且未实现确认外,其余监测点各工况下压力系数验证不确定度均较低,均实现了对应不确定度水平下的确认。
      结论  基于五方程的V&V方法能很好地反映文丘里管内部流动大涡模拟的误差,但计算资源消耗偏大,需进一步改进有限空间内部空化流动大涡模拟的V&V方法。

     

    Abstract:
      Objective  The adaptability of the accuracy of finite space cavitation flow described by the verification and validation (V&V) method needs to be analyzed quantitatively. To this end, flow under different cavitation numbers in a Venturi tube is subject to large eddy simulation (LES) to implement the V&V method, thereby expanding the application scope of verification and methods.
      Methods  First, the LES and Zwart-Gerber-Belamri (ZGB) cavitation model are used to simulate the flow in the Venturi tube under different cavitation numbers. The accuracy orders and numerical benchmarks of the pressure ratio and pressure coefficient under different working conditions are then calculated using the five-equation V&V method, and the verification uncertainties are calculated. Finally, the validation uncertainties are calculated and compared with the comparison error of the simulation values and experimental results.
      Results  Under the three cavitation numbers, the verification uncertainties of the pressure ratios are small, and the pressure ratios are validated at the uncertainty levels. When the cavitation number is σ=0.263 at x/Dth=9 and x/Dth=13, the verification uncertainties of the pressure coefficients are high, and the pressure coefficients are not validated. The verification uncertainties of the pressure coefficients at other monitoring points and working conditions are small, and the pressure coefficients are validated.
      Conclusions  The five-equation V&V method can smoothly reflect the error of the LES of Venturi flow, but the consumption is high, and the V&V method for the LES of internal cavitation flow in finite space requires further improvement.

     

/

返回文章
返回