화학공학소재연구정보센터
Experimental Heat Transfer, Vol.17, No.3, 161-179, 2004
Dynamics of thermal-hydraulic network control strategies
An experimental study of three common strategies for network temperature control is presented in this article. The test facility consists of a closed-loop cooling-water circuit with one primary and three secondary loops. There is a heat exchanger on the primary which cools the water returning from the secondaries, and there are heat exchangers on each one of the secondaries with water heaters to provide the thermal load. A different control strategy is applied to each secondary and proportional integral derivative (PID) controllers are used to respond to changes in the thermal load. The temperature difference at the primary loop heat exchanger is used as a criterion for comparison of the control strategies. Dynamic results relating to valve operation, temperatures, and flow rate are presented. The stability and reachability of the thermal control system is found to be affected by off-design operation of the cooling network.