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The method and the facility for investigations of radiant characteristics (total emissivity, transparence and reflectance) of semi-transparent fabrics and films are presented. The method is based on a measurements and comparison of effective emissivity of a test sample with two different opaque sublayers, whose radiant characteristics are known. These emissivity measurements are performed at the same temperatures. The determination of effective total emissivity of is carried out by means of the measurement of total radiant flux of a test sample with sublayer when ones are rotated in a heating isothermal zone with a controllable temperature. Facility permits to determine both the normal and hemispherical above radiant characteristics of semi-transparent fabrics and films in the temperature range from 300 to 900 K. The investigation results obtained for three glass fabrics are presented.

The numerical/experimental method for evaluation of radiant heat transfer and shields temperature as well as investigation results obtained for two variants of multi-layer insulation systems, irradiated by solar radiation, are presented. The experiment subsection describes the test method and examination of a test model, consisting of some (3-5) shields by means of irradiating one by known radiant flux. The test method permits to detect and evaluate the transparency effects of shields relatively external, in particular, solar radiation. On the base of the test results the temperatures and the effective radiant characteristics of shields are determined. The numerical alghorithm provides (with taking into account the above experimental data) evaluating the temperature of shields and radiant heat fluxes through multi-layer insulation systems with arbitrary number of shields.

The numerical/experimental method for, and results of, evaluating insulation solar radiation transmission effects on in-flight temperature field of a space vehicle are presented. The experiment subsection describes a new experimental method for evaluating materials solar-radiation transmittance, reflectance, and absorptance, as well as demonstrates test results for silica samples with various thicknesses. The calculation subsection includes (1) interpolation of the experimental data into a function of the insulation layer thickness and (2) the numerical solution of the transient heat conduction equation for a thermal protection fragment consisting of an insulation layer cemented to a metal plate. Fragment temperature calculation results for various near-Earth orbits and fibrous silica insulation layer thicknesses are presented. The results obtained show the essential influence of insulation solar-radiation transmission on space vehicle structure temperature in space flight.

The methods and facilities for determination of emissivity and absorptivity indicatrixes of materials and coatings are presented. The method for determination of emissivity indicatrix is based on diaphragming and measuring the axisymmetric radiant fluxes of a test sample. Two variants of the method realization are considered. The method and facility permit the investigation of the coatings on metals and insulation over the temperature range up to 1100 K to be carried out. The absorptivity indicatrixes are determined by means of a calorimetric method based on irradiating a test sample by collimating radiant flux. The method is realized for determination of solar absorptivity indicatrixes of coatings on any opaque materials in simulated space environment. The emissivity and absorptivity indicatrixes of several coatings are presented.