Calculation of the resistance coefficient of aero ballistic aircraft using MATLAB

摘要

When completing a course project or final qualification work in the specialty "Aircraft Control Systems", often a student is faced with the task of structural or parametric synthesis of a control system for given operating conditions. One of the most important stages of the synthesis is the calculation of aerodynamic forces for various parameters of the spatial and angular motion of the aircraft. In this case, it is necessary to use theoretical and empirical dependencies with a given accuracy of representation of the output parameters. This article shows the solution to the problem under consideration for aeroballistic aircraft using Matlab. Examples of calculations are considered, and options for using the functions of the MATLAB system based on the solution of an ordinary differential equation are shown. If from a computational point of view, these tasks do not present significant difficulties (and in this respect are traditional), then special attention is drawn to the fact that during training it is necessary not only to show examples of calculations, but to pay special attention to assessing the reliability of the result, methods for detecting errors or computational errors (which is especially important in the work of the designer of the aircraft control system and is a poorly formalized moment). The calculations (numerical experiments) performed in the article showed: how to most reliably calculate the integral of a given function over a segment, the method of calculating C_xfor hypersonic flight modes of an aeroballistic aircraft and the possibility of approximating an improper integral included in the calculation formula C_x for certain intervals of change in the number M. Considered examples it is advisable to use in the educational process to demonstrate the computational capabilities of the MATLAB system and to study methods for numerically solving problems with designing an aircraft control system.