PROGRESS IN EXPERIMENTAL RESEARCH ON HIGH-SPEED MULTI-BODY SEPARATION IN WIND TUNNEL

The high-speed multi-body separation mechanics problem is a core fundamental issue in the aerospace field. It involves the multi-physical strong interaction processes of multi-body separating under supersonic/hypersonic conditions, such as high-speed multi-body vehicles stage separation, dispersal separation, and the entry of space debris/meteorites (groups) into the atmosphere. The research on high-speed multi-body separation differs from the flow-around issues of single-body. The fluid mechanics phenomena generated by high-speed flow, such as shock waves, compression/expansion waves, and separated vortices, dynamically couple with the separated bodies. This complex unsteady dynamic process is one of the core challenges in the study of multi-body separation. Theoretical predictions and numerical simulations face certain limitations in dealing with highly dynamic, strongly coupled high-speed unsteady multi-body separation processes, making accurate and reliable ground experimental simulations particularly important. This paper provides a systematic review of the wind tunnel experimental techniques and application research on high-speed multi-body separation problems, mainly including static experiments, quasi-steady experiments, and dynamic separation experimental techniques and measurement methods. Secondly, it summarizes the complex flow phenomena and physics of experiments on high-speed multi-body separation. Furthermore, it systematically analyzes the limitations and challenges of current high-speed multi-body separation experimental techniques and outlines the future development direction of multi-body separation experiments. The core scientific issue in high-speed multi-body separation wind tunnel experiments lies in the nonlinear aerodynamic interference, unsteady flow, and motion coupling among multiple bodies. The key technologies that urgently need to be addressed in wind tunnel experimental simulation include millisecond-level dynamic experimental technology, precise simulation of multi-body poses, and aerodynamic load prediction, etc. It is expected to provide some meaningful insights into the basic experimental research of multi-body separation and promote the development of China's aerospace high-speed multi-body vehicle equipment.