艇载风压计测量平流层大气风场可行性分析

本文提出了一种基于搭载平流层飞行器对平流层大气风场进行原位探测的探测系统,并详细介绍了其工作原理、计算公式和风洞实验结果。实验室测试中,该探测系统的理论测量误差值≤2.5 m/s。在常温下的风洞试验中,该系统表现出了良好的工作性能、系统稳定性和测量准确度。在和实验室的风向、风速对比试验中的相关性均超过了0.99,风速的平均绝对偏差为0.67 m/s,风向的绝对平均偏差为2.4°。2022年,中国气象局气象探测中心利用平流层超压气球搭载该系统在海拔19 km的平流层大气中进行了原位探测试验,对所搭载平台周围的风速和风向进行了探测,并对探测结果进行了比对分析。与平台轨迹算法进行比对结果显示,该系统具有较好的一致性;与NCEP_FNL再分析数据进行比对,显示出东西向风速的相关性较好,达到了0.795,而南北风速的相关性较差,仅为0.33。试验结果表明,在平流层飞行器上搭载该探测系统可以有效地探测平流层大气风场,对于获得平流层大气环境数据集、提供大气环境预报服务、开发平流层浮空器、监测平流层飞行器周围的大气环境、规划飞行路线和区域停留等方面具有巨大的应用潜力。     

A wind tunnel for the calibration of Mars wind sensors

A major limitation in the development of wind sensors for use on Mars is the lack of suitable testing and calibration facilities. A low-density wind tunnel has been developed at Oxford University for calibration of wind sensors for Mars landers, capable of providing stable or dynamically varying winds, of air or carbon dioxide, at Martian pressures (5-10 mbar) and speeds (0.5-30 m/s), and temperatures of 200-300 K. The flow field in the test section was calculated using analytical and computational modelling techniques, and validated experimentally using a pitot probe. This facility's stability and accuracy offer significant advantages with respect to previous calibration facilities.     

An integrated laser anemometer and dust accumulator for studying wind-induced dust transport on Mars

Windborne dust is one of the most important and dynamic factors affecting the Martian surface and its atmosphere, yet there lacks a detailed physical understanding how it is transported. We present a miniature laser-based optoelectronic instrument for use on a Mars lander. It integrates sensors capable of quantifying important parameters needed for the understanding and modeling of dust transport on Mars, these include wind speed, wind direction, suspended dust concentration, dust deposition and removal rates as well as the electrification of the Martian dust. Dust electrification has been seen from experimental simulations to be of considerable importance to the processes of adhesion and cohesion, specifically prompting the formation of low mass density dust aggregates. Testing of this prototype instrument has been performed under simulated Martian conditions in a wind tunnel facility. The results and analysis of its functionality will be presented.