高马赫数飞行技术的发展对飞行员的生命保障系统提出了新的挑战。本文旨在基于现有研究技术下探讨在极端高速飞行条件下,保障飞行员生命安全和身体健康的关键技术的研究进展。本文首先对高马赫数飞行器飞行条件下对人体生理的影响进行了探讨;随后,概述了高马赫数飞行器的典型飞行特征以及面对高空、低压、高马赫数飞行环境下生命保障技术设计应当具备哪些基本需求;最后,综合研究了高马赫数飞行条件下生命保障的设计在当下有哪些进展与突破。此外,本研究对现有高马赫数飞机生命保障系统进行了总结,提出高马赫数飞机生保技术路线图进行研究,以进一步提高高马赫数飞行器生命保障技术的性能和可靠性。The development of high Mach number flight technology poses new challenges to the life support system of pilots. The purpose of this paper is to explore the research progress of key technologies to safeguard pilots’ life safety and physical health under extreme high-speed flight conditions based on existing research technologies. This paper firstly discusses the impact on human physiology under the flight conditions of high Mach number vehicles. Subsequently, it outlines the typical flight characteristics of high Mach number vehicles and the basic needs for life support technology design in the face of high-altitude, low-pressure, and high Mach number flight environments. Finally, it comprehensively investigates what advances and breakthroughs have been made in the design of life support under the flight conditions of high Mach number. In addition, this study summarises the existing high-Mach aircraft life support system and proposes a roadmap for high-Mach aircraft life support technology to be studied in order to further improve the performance and reliability of high-Mach aircraft life support technology.
The compressibility of fluids has a profound influence on oscillating bubble dynamics,as characterized by the Mach number.However,current theoretical frameworks for bubbles,whether at the first or second order of the Mach number,are primarily confined to scenarios characterized by weak compressibility.Thus,a critical need to elucidate the precise range of applicability for both first-and second-order bubble theories arises.Herein,we investigate the suitability and constraints of bubble theories with different orders through a comparative analysis involving experimental data and numerical simulations.The focal point of our investigation encompasses theories such as the Rayleigh–Plesset,Keller,Herring,and second-order bubble equations.Furthermore,the impact of parameters inherent in the second-order equations is examined.For spherical oscillating bubble dynamics in a free field,our findings reveal that the first-and second-order bubble theories are applicable when Ma≤0.3 and 0.4,respectively.For a single sonoluminescence bubble,we define an instantaneous Mach number,Mai.The second-order theory shows abnormal sensibility when Mai is high,which is negligible when Mai≤0.4.The results of this study can serve as a valuable reference for studying compressible bubble dynamics.
