Equipment for testing of cooling loops - ATLAS Upgrade (Instrument Development)

计划中的Atlas Upgrade硅微带探测器系统将采用与现有系统类似的蒸发冷却系统，但将使用二氧化碳而不是碳氟化合物作为冷却气体，以改善小质量流的传热和冷却剂对壁的传热性能。这是可以实现的，因为相对于现有的氟碳气体，二氧化碳的潜热容量较大，然而，利用这一点需要的操作压力远远超过目前的压力系统。因此，当工作压力超过150bara时，必须对冷却系统进行充分的测试，以防止冷却元件发生灾难性故障。通过这笔资金提供的设备，原型和最终设计冷却回路的安全性和完整性测试将成为可能，并将展示我们处理二氧化碳冷却剂泄漏和突出其他潜在故障来源的策略。

The planned Atlas Upgrade silicon micro-strip detector system will employ an evaporative cooling system similar to the current system, but will utilize CO2 rather than fluorocarbon as the coolant gas in order to improve the heat transfer and coolant-to-wall heat transfer properties for small mass flows. This can be achieved due to the large latent heat capacity of CO2 relative to the existing fluorocarbon gas, however the utilization of this requires operating pressures far in excess of the current pressure system. As such, with operating pressures in excess of 150bara, it is essential to provide adequate testing of cooling systems to prevent catastrophic failure of the cooling elements. Safety and integrity testing of prototype and final design cooling loops will made possible by the equipment provided by this funding and will demonstrate our strategies to deal with both CO2 coolant leakage and highlight other potential failure sources.