Design Of Near-space Sounding Temperature Senso

Near space refers to the space between 20 and 100 km above the ground.In the past,the atmospheric environment in near space has not been studied deeply in domestic and foreign meteorological fields.However,with the progress of science and technology,the important development and application value of near space has attracted wide attention in the world.In particular,China plans to put ultra-high speed aircraft into use in the future.Because of its extremely fast flight speed,its flight environment must have the characteristics of small resistance and interference,so near space is its best flight environment.Other studies have shown that the meteorological environment in near space is closely related to long-term weather prediction.Therefore,to detect the atmospheric environment in the near space is helpful for meteorological prediction,and at the same time,the flight environment of sub-orbital vehicles that will be put into use in China is also studied in advance,which promotes the development of China’s space industry to a certain extent.In order to solve the problem that it is difficult for traditional sounder to exceed the flight height of 30 ～ 80 km,a near space sounding sensor is designed,which uses the rocket dropdown method and detects the atmospheric environment of 30 ～ 80 km.Its main temperature measuring element is a sounding temperature sensor with an array of thermocouples,which can reduce the temperature measurement error caused by high-altitude solar radiation.Firstly,the radiation errors of thermocouple sensor probes are numerically solved using computational fluid dynamics(CFD)method to obtain the most appropriate probe size.Then,the solar radiation error ratio between sensor probes with different surface reflectivity is calculated using the same method,and the true ambient temperature is calculated based on the measured ratio and the formula.Finally,the solar radiation error is solved and processed by SVM algorithm.To ensure the integrity of the sensor system,a set of hardware and software systems is designed to quickly collect and communicate atmospheric data in near space,including sensor temperature measurement module,data communication module and task scheduling module.In addition,in order to simulate the meteorological environment in the near space,simulating the atmospheric environment during sensor drop acquisition using a low-pressure wind tunnel,and an experimental platform is formed with the solar simulator to generate real sunlight for experimental research.The measured temperature calculated from the ratio of radiation errors between sensor probes is compared with the standard ambient temperature after fitting with the SVM algorithm.The experimental results show that the average measurement error of temperature sensor on near space radiosonde system is 0.107 ℃,and the root mean square error is 0.22 ℃.This indicates that the sensor designed in this paper has higher measurement accuracy and can adapt to the atmospheric environment of near space better,while guaranteeing the measurement speed.