Chen, Ruey-HungAbramczyk, Seth2022-09-292022-09-292021-01-0112472http://hdl.handle.net/11603/26043Accurate knowledge of the optical properties of spacecraft components, especially external components, is critical for proper spacecraft thermal design. The effective emissivity of isogrid (an array of equilateral triangular cavities) is not well understood, which poses a challenge for spacecraft thermal management. In this theses the effective emissivity of isogrid with a prescribed base temperature and nonisothermal walls is examined. The temperature profile of the cavity's walls and the overall effective emissivity of the cavity are found using Thermal Desktop with Monte Carlo ray tracing. The effective emissivity's dependence on the wall height, wall thickness, wall resistance, and surface emissivity are examined. The existence of a critical wall height, and the contributing factors to this critical height, are discussed. Comparisons between isogrid and cavities with different base geometries are made. A variable emissivity isogrid spacecraft radiator concept employing the cavity effect is proposed, and mechanisms for achieving this are discussed.application:pdfThis item may be protected under Title 17 of the U.S. Copyright Law. It is made available by UMBC for non-commercial research and education. For permission to publish or reproduce, please see http://aok.lib.umbc.edu/specoll/repro.php or contact Special Collections at speccoll(at)umbc.eduCavity EffectEffective EmissivitySpacecraft RadiatorSpacecraft Thermal ControlVariable Emissivity RadiatorText