Abstract: A closed loop control apparatus utilizes a cooling effect sensor to measure the cooling capacity of a fluid in a supply conduit connected to one or more thermal loads. The sensor includes an electrical heater that is regulated to heat a sampled portion of the cooling fluid at a known rate, and a temperature sensor positioned downstream of the heater to measure the temperature of the heated fluid and thereby determine the cooling effect or capacity of the fluid. A control signal developed by the temperature sensor is fed back to a flow modulating valve that adjusts the flow of cooling fluid to the thermal loads.

Abstract: A closed loop control apparatus utilizes a cooling effect sensor to measure the cooling capacity of a fluid in a supply conduit connected to one or more thermal loads. The sensor includes an electrical heater that is regulated to heat a sampled portion of the cooling fluid at a known rate, and a temperature sensor positioned downstream of the heater to measure the temperature of the heated fluid and thereby determine the cooling effect or capacity of the fluid. A control signal developed by the temperature sensor is fed back to a flow modulating valve that adjusts the flow of cooling fluid to the thermal loads.