Numerical simulation of flows in the ONERA S3Ch transonic wind tunnel

Abstract

This paper investigates the flow field within the high‑speed leg of the ONERA S3Ch wind tunnel as part of the NATO activity AVT‑387, “Common Research Wind and Water Tunnel for CFD Verification and Validation.” The objective of the study is to analyze the flow in the S3Ch test section under various flow conditions and geometrical configurations in order to develop a numerical twin of the test section. The empty test section is investigated at a Mach number of 0.7. The test conditions are achieved either under fully subsonic conditions using a straight test‑section geometry, or under transonic flow conditions through the use of a sonic throat, which represents a particularly challenging case for CFD solvers. The study is conducted within the framework of the NATO activity and is intended to serve as a benchmark for several CFD solvers and meshing techniques, with the aim of identifying best practices for this type of configuration.