Abstract: With the pursuit of higher performance for reusable launch vehicles, the high-precision atmospheric models including dynamic effects such as season and geography should be introduced to replace the currently prevalent annual average standard atmospheric model, enable high accuracy evaluation of thermal environment discrepancies during flight. Utilizing atmospheric parameters collected by the SABER payload on the TIMED satellite from 2002 to 2018, a study was conducted on the influence of statistical distributions of atmospheric parameters, based on typical monthly intervals, on the thermal environment of vehicles flying at high speeds in the upper mesosphere (70km and 80km) over latitudes typical of China's region. By normalizing the results from the standard atmospheric model, the effects of latitude variation and seasonal variation on the thermal environment of high-speed flight in the upper mesosphere were obtained, revealing distribution characteristics that deviate from the standard atmospheric model. The results show that seasonal variation has almost no effect on atmospheric distribution in equatorial regions, with the expected fluctuation range close to 53% of the heat flux predicted by the standard atmospheric model. Extreme high and low heat fluxes both occur in high-latitude regions. The engineering design method of using the standard atmosphere plus fixed biases is insufficient to cover such complex real-world variations.

Key words: atmosphere model, atmospheric dynamics, aeroheating, mesosphere, reusable launch vehicle