Derivation of forcing functions for Monte Carlo atmospheric gust loads analysis

Abstract

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Atmospheric Flight Gust Loads Analysis

“…As discussed in Ref. 22, the turbulence/gust forcing functions are only appropriate for wavelengths greater than 500 ft. Critical spacecraft loads are often obtained with gust profiles that include shorter than 500-ft wavelengths. Therefore, at this time, the procedure presented here is not recommended for spacecraft gust load analysis, unless the critical loads are defined by wavelengths greater than 500 ft.…”

“…The turbulence/gust profiles were developed from a large number of measured wind velocity (magnitude and direction) profiles obtained with Jimsphere balloons (Ref. 22). Most were associated with day-of-launch operations.…”

“…Complete details of the forcing function development are presented in Ref. 22. Figure 2 presents a typical profile.…”

“…The first step was to develop two large families of gust forcing functions-one for the Eastern Range (ER) of the United States, located in Florida, and one for the Western Range (WR) of the United States, located in California. 21 ' 22 Next, gust loads analyses were performed using each of the new forcing functions. The solution procedure was identical to that used with the synthetic profiles, except that instead of using a one-minus-cosine profile, actual wind profiles were used.…”