THERMAL SIMILARITY OF SPACE OBJECTS OF STANDARD CONFIGURATIONS
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Thermal similarity of objects of various configuration is defined by equality of their stationary surface average temperatures in the Earth shadow that is equivalent to equality of their effective irradiance coefficients by own thermal radiation of the Earth. Cone, cylinder and sphere are chosen among standard configurations. Unlike two last figures, calculation of irradiance coefficient for conic object is the most difficult and contains a number of uncertainties. The method of calculation for integrated and effective irradiance coefficients of space object with a conic form is stated which is typical for fragments of spacecrafts. Integrated irradiance coefficients define the average thermal balance on a lateral surface of the cylinder and cone, and also full power balance on a sphere surface. Effective irradiance coefficients define a full falling specific stream of the Earth’s radiation on the whole surface of cylindrical or conic object taking into account their bases. By data about effective irradiance coefficients, the average stationary temperatures of space objects in the Earth shadow are defined, as well as on the trajectory part illuminated by the Sun taking into account two additional components of power balance – direct sunlight and reflected by the Earth. Researches were conducted in the height change range for an orbit from 200 to 40000 km depending on a tilt angle of the cylinder and cone axis relative to zenith-nadir line. Similarity conditions for the cylinder and cone are defined at equal ratio sizes of the figure height to base diameter.