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А.А. Солуянов

26

ISSN 0236-3941. Вестник МГТУ им. Н.Э. Баумана. Сер. Машиностроение. 2017. № 2

Солуянов Андрей Аркадьевич

— канд. техн. наук, старший научный сотрудник Воен-

но-космической академии имени А.Ф. Можайского (Российская Федерация, 197198,

Санкт-Петербург, Ждановская ул., д. 13).

Просьба ссылаться на эту статью следующим образом:

Солуянов А.А. Расчет внешних тепловых потоков на космический аппарат методом

z

-буфера // Вестник МГТУ им. Н.Э. Баумана. Сер. Машиностроение. 2017. № 2. C. 15–27.

DOI: 10.18698/0236-3941-2017-2-15-27

SPACECRAFT EXTERNAL HEAT FLOW ANALYSIS BY

Z

-BUFFER METHOD

A.A. Soluyanov

vinivka442@yandex.ru

Mozhaisky Military Space Academy, St. Petersburg, Russian Federation

Abstract

Keywords

Determining the external heat flow from direct sunlight to

spacecraft is an important stage in analysis and design of

the spacecraft thermal control. The Earth IR and albedo

radiation provide the noticeable contribution in total

spacecraft heating in case when a spacecraft is operating in

Low Earth Orbit. The task gets significantly more compli-

cated in case of complex spacecraft geometrical configura-

tion in presence of mutual shading by spacecraft compo-

nents. The zonal method is often applied to simplify calcu-

lations when visible terrestrial region is subdivided into a

finite number of surface area zones. The radiation from

each zone is approximated as a parallel beam is irradiated

from a point source placed in the zonal center. Direct

sunlight is considered to be a parallel beam from the point

source as well, therefore it is possible to calculate the total

external heating using the same approach. The key point

of the approach implementation is to choose an algorithm

for calculating the spacecraft external surface projected

area facing radiation from each point of the source if there

is a possibility of spacecraft components mutual shading.

Known algorithms based on ray-tracing could experience

a significant loss of performance being applied to complex

models, especially containing components of non-regular

shape. This paper presents a method for carrying out such

calculations on a meshed spacecraft CAD model with its

external surface subdivided into a finite number of faces of

any kind (triangles, quadrangles or isoparametric faces).

The method uses the

z

-buffer (or depth buffer) technique

well-known in the field of computer graphics. Advantages

of the method are straightforward implementation, ap-

plicability to a geometrical model of any complexity and

acceptable performance which is not affected by the non-

regularity of geometry

Spacecraft, meshed geometrical mo-

del, mutual shading, pixel, z-buffer,

depth buffer