不同攻角下超声速降落伞伞绳的影响研究

文章基于一种简易＂浸入边界技术＂与流固耦合方法对超声速来流条件下的三维降落伞系统进行了数值模拟。研究中,降落伞系统包括前体和伞体,两者通过伞绳连接。文章的研究目的是分析不同攻角下降落伞伞绳对于降落伞系统周围复杂非定常流场的影响,以及对降落伞性能表现的影响。结果表明：在较小的前体和伞体距离下,由于攻角的影响,非定常流场结构呈现上下不对称,并且上下伞绳激波形成时间不同步。随着攻角的增加,上下面的伞绳激波形成时间出现推迟,并且有变弱的趋势。另外,由于攻角与伞绳的综合影响,伞内表面的时间平均压力分布在5o攻角时最小,而在10o攻角时最大,阻力系数却随着攻角的增加而增加

复现高超声速飞行条件下10°尖锥标模气动力特性试验研究

综述了应用中科院力学所的JF12长试验时间激波风洞中,在复现40km高度,飞行马赫数7的试验条件下,开展的10°尖锥标模天平测力试验研究结果

高超声速激波风洞气动力测量技术研究

高超声速激波风洞气动力测量技术研

超大量程测力天平校准系统

"用于载荷量成在2吨以下的杆式应变天平静态校准。，主要技术指标: 额定载荷范围： 轴向力Fx=±5.0kN； 法向力Fy=±15.0kN； 侧向力Fz=±6.0kN； 滚转力矩Mx=±0.5kN.m； 偏航力矩My=±0.8kN.m； 俯仰力矩Mz=±1.5kN.m； 精度≤0.05%F.S

高超声速喷管设计理论与方法

在高超声速飞行技术领域,特别是涉及到高焓气体流动的研究,高超声速风洞试验仍然是目前最可靠的研究手段.对于高超声速风洞研发,其中最重要的一项性能指标就是风洞流场的品质,取决于喷管设计采用的理论与方法,是风洞设计最关注的一项核心技术.针对二维轴对称型面喷管设计,本文首先综述了传统高超声速喷管设计的主要理论和常用方法,它们在高超声速喷管设计中曾经发挥了重要作用,包括理论方法,近似方法和基于两者的修正方法.然后,考虑高温气体效应,分析了高焓喷管设计时面临的困难与问题,从流动介质物性变化、高温边界层发展和非平衡过程效应三方面,综述了国内外在高超声速高焓喷管设计方面的研究进展.最后,对于高焓喷管的设计理论和方法的发展作了展望,期望对于推动我国高超声速高焓喷管设计技术的发展提供一些有意义的启示.&nbsp;</p

Theories and methods for designing hypersonic high-enthalpy flow nozzles

Hypersonic high-enthalpy wind tunnels have been a challenge to ground tests in aerospace research area for decades and its test flow uniformity is one of the most important parameters for evaluating wind tunnel performances. Regarding to the performance requirement, theories and methods for designing hypersonic flow nozzles at high enthalpy conditions are quite difficult, but very interesting topics, especially when air molecule dissociations take place in wind tunnel test gas reservoirs. In this paper, fundamental theories and important methods for nozzle designs are briefly reviewed with the emphasis on two-dimensional axisymmetric nozzles for hypersonic high enthalpy wind tunnels, including the Method of Characteristics (MOC), the graphic design method, the Sivells method, the theory for boundary correction, and the CFD-based design optimization methods. These theories and methods had been proposed based on several physical issues, respectively, which play important roles in nozzle flow expansion processes. These issues cover the expansion wave generation and reflection, the boundary layer development, the real gas effect of hypersonic high-enthalpy flows. Difficulties arising from applications of these methods in hypersonic high-enthalpy nozzle design are discussed in detail and the state of the art of the nozzle design technologies that have reached for decades is summarized with some brief comments. Finally, the prospect for the hypersonic nozzle design methods, and its numerical and experimental verifications are provided with from authors' viewpoint for readers' reference.(c) 2021 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)