Development, evaluation, and validation of a robust virtual sensing method for determining water flow rate in chillers

Abstract

Monitoring the water flow rate through chillers is necessary and important for safety and optimal operation of a chiller system. Conventional measuring methods are reluctantly accepted by end users due to high implementation cost and continuous maintenance requirements. In this study, a cost-effective virtual sensing method was developed to determine the water flow rate in chillers using generally available chiller onboard measurements. The method was implemented, evaluated, and demonstrated in both a laboratory test environment and a field test environment. The test results show that the method is capable of accurately monitoring the water flow rate in the condenser loop and evaporator loop using low-cost and noninvasive measurements obtained while the system is operating. In terms of application, the proposed method is promising for embedment within a chiller onboard controller or a monitor system to monitor actual water flow rate in the chiller system.

Acknowledgments

Xinzhi Zhao, PhD, Student Member ASHRAE, is Research Engineer. Mo Yang, Student Member ASHRAE, is Ph.D. Student. Haorong Li, PhD, Member ASHRAE, is Assistant Professor.