A parametric study on the cooling characteristics of an infrared detector cryochamber

✍ Scribed by Ho-Young Kim; Byung Ha Kang; Dae-Young Lee

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 782 KB
• Volume: 40
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/s0011-2275(01)00033-9

✦ Synopsis

This work investigates the steady and transient cooling characteristics of an infrared (IR) detector cryochamber, which has a critical eect on the cooling load that a refrigeration system should carry away. The current thermal modeling considers the conduction heat transfer through a cold well, the gaseous conduction due to outgassing, and the radiation heat transfer. The steady cooling load is obtained by using a ®n equation. The transient cooling performance, i.e., the cool-down time, is determined using a ®nite dierence method. It is shown that the gaseous conduction plays an important role in determining the steady cooling load, whereas it has a negligible eect on the cool-down time due to a short thermal penetration depth. The steady cooling load increases linearly with the bore conductivity when it is high. However, when the bore conductivity is low and the gas pressure is high, the cooling load becomes more sensitive to the bore conductivity. The steady cooling load increases linearly with the dierence between the ambient temperature and the detector operation temperature, but rather the cool-down time is proportional to the square of the temperature dierence. The results of this work can be used to determine the thermally optimal design and operation conditions of the cryochamber.