Approximate Analysis of a Flat, Circular Parachute in Steady Descent

摘要

A theory is presented for the stress analysis of a flat, circular parachute in steady, vertical descent. Unlike previous treatments of the problem, this theory does not assume that the shape is known. Instead the theory presents relations between the pressure distribution in the opened condition and the shape, drag and stresses in lines and fabric. The theory results in a non-linear third order system of ordinary differential equations with boundary conditions at both vent and skirt. This system was solved by a computer program based on the Runge-Kutta method of numerical integration. The results are in fairly good agreement with measurements on parachutes. The computer program can be used for studies of effects of design changes on shape, drag and stress, and the results of a small study of this sort are included. (Author)