Model validation method by considering uncertainty for numerical simulation

考虑不确定性的数值模拟模型确认方法

¹ Southwest Technology and Engineering Research Institute, Chongqing 400039, China
² School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China

Received: 9 October 2022

Abstract

There is a great amount of uncertainties in the whole life cycle of a flight vehicle, which can induce anon-negligible uncertainty in the numerical simulation output, then the model validation of the numerical simulation is the premise of design optimization. Lots of researches on the uncertainty quantification (UQ) of numerical simulation has been carried out. However, literature has rarely seen works about performing scientific model parameter correction by using the results of UQ and establishing a closed-loop procedure of numerical simulation model validation in a systematic way. Therefore, a numerical simulation model validation method by considering uncertainties is proposed, and a model parameter correction approach based on high-quality small samples is developed, and then a closed-loop model validation process composed by uncertainty quantification, global sensitivity analysis, and parameter correction strategy to provide a scientific and systematic procedure for constructing high-fidelity numerical simulations is established. The effectiveness and advantages of the model validation method is verified through airfoil simulation.

摘要

飞行器在其研发、生产和使用的整个寿命周期中都存在大量不确定性, 这会导致数值模拟输出也具有不可忽视的不确定性, 因此开展基于数值模拟技术的飞行器设计前必须进行模型确认。目前围绕数值模拟已开展了大量不确定性量化(uncertainty quantification, UQ)的研究工作, 但是如何基于UQ的结果科学地进行模型参数修正, 形成系统的数值模拟模型确认的闭环流程, 构建高可信的数值模拟预测模型, 还较少有研究报道。为此, 提出一种考虑不确定性的数值模拟模型确认方法, 发展一种基于优质小样本的模型参数修正策略, 建立一套融合不确定性量化、全局灵敏度分析、参数修正的模型确认闭环流程, 为构建高保真的数值模拟提供科学系统的思路, 并通过翼型的仿真算例验证了该方法的有效性。