1. 제 목 :Temperature Field Inversion and Break-Down at the Interface of


Semi-Transparent Two-Layer System in Radiative Heat Transfer





2. 연 사 : Professor Yoram Zvirin


Faculty of Mechanical engineering


Technion, Israel Institute of Technology


Haifa, Israel





3. 일 시 : 2001년 9월 12일 (수) 16:00 – 17:00





4. 장 소 : 301동 1512호





5. 내 용 : An analys is presented of pure radiation heat transfer in a system of semi-transparent two layers, with a diffuse or partially diffuse interface. Two cases are considered, of "optically closed" and "optically open" systems. In the former case, heater and cooler surfaces with angular-dependent emissivities enclose the two layers. In the latter case, the system is irradiated by a collimated heat flux on one side and the two boundary surfaces radiate to space. Two interesting phenomena have been found from the results obtained by the mathematical/numerical methods: inversion and break-up of the temperature field. In some cases, depending on the radiation properties of the heater and cooler surfaces and on the refraction indices of the layers and the specular/diffuse shares of the interface: the temperature decreases from the side facing the heater to the interface, exhibits a sharp jump increase across it, and then decreases, again, in the second layer (facing the cooler). The whole temperature curve is sometimes higher in the second layer than in the first one. These phenomena occur due to collimation of the radiative heat flux at the boundary surface facing the heater and "de-focusing" the flux at the diffuse (or partially diffuse) interface.








6. 문 의 : 기계항공공학부 이 준 식 교수 (☏ 880-7117)