CEBAF Cryounit Loss of Vacuum Experiment
In order to test the sizing of the safety relief devices provided for the Continuous Electron Beam Accelerator Facility’s 42 1/4 Cryomodules, several loss of vacuum experiments have been planned with a modified 1/4 Cryomodule called the Cryobench. The first of these experiments, presented here, is a controlled spoiling of the insulating vacuum to air. The most credible vacuum failure was simulated with in a 3.2 mm diameter hole being opened to the vacuum space yielding an air flow of 0.0033 kg/s and corresponding peak heat fluxes of 749 W/m2 just before the rupture disc opened. The maximum calculated helium mass flows of.025 kg/s indicate that the process relief valve provided on each cryomodule is adequate to handle this type of vacuum failure. The experimental configuration and recorded data are presented and discussed.
KeywordsRelief Valve Orifice Plate Vacuum Space Thermal Shield Pneumatic Valve
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