探寻科学计量科研管理方法 夯实企业发展基础

计量作为必不可少的技术基础,是企业核心能力的重要组成,是科技创新的重要支撑,为企业的发展发挥着重要基础性支撑性作用。计量科研是计量科技创新和计量保障能力持续提升的主要途径。本文介绍了一些计量科研项目管理经验,并根据目前面临的新形势提出了进一步推进计量科研工作的设想。     

三相线钉扎的大液滴蒸发实验

利用实践十号返回式科学实验卫星蒸发对流箱,开展了三相线处于钉扎状态且接触半径大于毛细长度的无水乙醇大滴在加热PTFE表面蒸发的地基科学实验。实验发现,液滴体积随时间线性递减,但钉扎大液滴蒸发过程中没有出现恒定接触角（CCA）阶段。与小液滴蒸发的恒定接触半径（CCR）阶段相同,大液滴的平均蒸发速率也与初始体积无关,表明受重力影响明显的大液滴蒸发主要发生在三相线附近区域。瞬时蒸发速率经历了迅速上升和之后的长时间内保持稳定两个阶段。与数值模拟结果对比分析发现,准静态扩散模型低估了三相线处于钉扎状态的大液滴瞬时蒸发速率,而同时考虑蒸气扩散与空气中自然对流经验模型的准确性取决于实验所用工质。     

ESA部长级会议确定未来发展方向和投资水平

2022年11月22‒23日,欧洲空间局（ESA）成员国部长级会议在法国巴黎召开,决定共同投资约169亿欧元开展各项空间活动和计划,相比2019年部长级会议,投资额大幅增长17%。ESA将通过在对地观测、科学计划、载人和无人探索、通信与综合应用、导航、空间安全、空间运输、技术等重点领域的投资,加强其在空间领域的自主性、领先地位和可持续发展能力。     

SAX overview

Information is given concerning the satellite for X-Ray Astronomy SAX, a project of the Italian Space Agency in collaboration with the Netherlands Agency for Aerospace Programs, due for launch at end 1993.

The scientific objectives and the payload are described, together with the ground system structure and organization.     

Progress of super-pressure balloon development: A new “tawara” concept with improved stability

The super-pressure balloon (SPB) has been expected to be a flight vehicle that can provide a long flight duration to science. Since 1997, we have developed the SPB. Now we are at the phase of developing an SPB of a practical size. In 2009, we carried out a test flight of a pumpkin-shaped SPB with a 60,000 m³ volume. The undesirable result of this flight aroused us to resolve the deployment instability of the pumpkin-shaped SPB, which has been known as one of the most challenging issues confronting SPB development. To explore this deployment issue, in 2010, we carried out a series of ground tests. From results of these tests, we found that an SPB design modified from pumpkin, named “tawara”, can be a good candidate to greatly improve the deployment stability of the lobed SPB.     

计算辐射冷却推力室不稳定温度场的隐式格式

导出了计算液体火箭发动机辐射冷却推力室不稳定温度场的隐式差分格式,并作了线性化处理。据此编制通用程序,可以计算任意辐射冷却推力室的不稳定温度场。     

以竞赛为契机丰富第二课堂--从全国大学生电子设计竞赛谈学生课外科技活动的开展

全国大学生电子设计竞赛对提高学生的综合素质和动手能力很有必要,同时竞赛也向大学生的科技活动提出了更高要求。加强对学生科技活动的指导,规范科技活动与课内、课外有机结合,设立奖励基金,是提升大学生科技创新能力的有效途径。     

Development of a super-pressure balloon with a diamond-shaped net

The essential reason of the lobed-pumpkin shaped super-pressure balloon to withstand against the high pressure is that the local curvature of the balloon film is kept small. Recently, it has been found that the small local curvature can also be obtained if the balloon is covered by a diamond-shaped net with a vertically elongated shape. The development of the super-pressure balloon using this method was started from a 3-m balloon with a polyethylene film covered by a net using Kevlar ropes. The ground inflation test showed the expected high burst pressure. Then, a 6-m and a 12-m balloon using a polyethylene film and a net using the Vectran were developed and stable deployment was checked through the ground inflation tests. The flight test of a 3000 m³ balloon was performed in 2013 and shown to resist a pressure of at least 400 Pa. In the future, after testing a new design to relax a possible stress concentration around the polar area, test flights of scaled balloons will be performed gradually enlarging their size. The goal is to launch a 300,000 m³ super-pressure balloon.