Improvements on APTC (Ambient Pressure Thermal Cycling) Chamber Regarding Temperature Homogeneity and Energy Consumption
Abstract
This paper describes the working principles of IABG's Ambient Pressure Thermal Cycling chamber (an alternative to thermal-vacuum tests for some cases) and our activities to characterize and improve the system. For example a 3D grid of 64 temperature sensors was installed inside the test volume, in order to determine reliable temperature distribution data for standard operating conditions. Camera monitoring inside the temperature control / fan box allowed us to study the processes. A modification of the direct injection of liquid nitrogen (for efficient cooling) by installation of defined spray nozzles improved the temperature distribution. The characteristics of the original LN2 injection valve caused enormous consumption of liquid nitrogen and electrical power even at constant chamber temperatures. A new valve with a different control characteristic reduced this standby consumption remarkably.
- Publication:
-
13th European Conference on Spacecraft Structures, Materials & Environmental Testing
- Pub Date:
- June 2014
- Bibcode:
- 2014ESASP.727E.147S