Uzay araçlarında kullanılan çeşitli malzemelerde temas basıncının ısıl temas direncine etkisi

In this study, it is aimed to measure the thermal contact resistances of solid materials (esp. honeycomb cored composite panel samples and their interactions with metallic samples) that are used in spacecraft design by taking into account joint pressure under vacuum environment. It is needed to design a measurement device that does not exist in our country in order to measure the thermal contact resistances of solid materials. Thermal Contact Resistance (TCR) measurement device follows the similar approach that is mentioned in ASTM E1225 "Standard Test Method for Thermal Conductivity of Solids Using the Guarded-Comparative-Longitudinal Heat Flow Technique". Heat flux transducers are used on behalf of meter bars. Larger sample sizes are able to be exposed to the thermal properties specification measurement by the usage of heat flux transducers. Measurement device is also capable to obtain thermal conductivity of the samples subjected to the measurements. A reference stainless steel material was used to characterize the output of heat flux transducers. Stainless Steel Reference sample thermal conductivities were specified at three different pre-defined reference sample temperature (-30°C, 10°C & 50°C) in accordance with ASTM E1225. Measurements were conducted at three different temperatures to obtain characteristic function of heat flux transducers during commissioning of TCR measurement device. Thermal contact resistance measurement were conducted after commissioning of TCR measurement device. Aluminum face sheeted honeycomb-cored composite panel and Stainless Steel reference samples were subjected to the measurement. During the measurements, it was observed that uni-directional heat flow over samples was not obtained. As a consequence of detailed evaluation, thermal conductivity of each sample pays a crucial role to obtain uni-directional heat flow over samples.