SE-14-C015 -- Refrigeration Systems Failures Due to Sudden Evaporation and Condensation Phenomena PDF

Industrial, commercial, and residential refrigeration systems incorporate two-phase flow in their evaporators and condensers, where the pressure and temperature of refrigerant are typically controllable. However, if the rate of phase-change increases drastically for any reason, pressure spikes and shock waves may be generated in a very short period of time. Depending on the pressure, temperature, surrounding conditions, and mechanical integrity of the system, these incidents can be very destructive. In this study, complex two-phase sudden evaporation and condensation phenomena such as Condensation Induced Shock (CIS), Vapor-Propelled Liquid Slug (VPLS), Condensation Induced Water Hammer (CIWH), Boiling Liquid Expanding Vapor Explosion (BLEVE), and Boiling Liquid Compressed Bubble Explosion (BLCBE) pertaining to HVAC&R systems are reviewed and discussed. A case study is reviewed with an estimate of the magnitude of pressure spikes for possible scenarios that may occur in HVAC&R systems. Recommendations for system design are proposed to mitigate the damage that might occur due to these rapid phase-change phenomena.