Lead Performer: Oak Ridge National Laboratory – Oak Ridge, TN
DOE Total Funding: $900,000
Project Term: October 1, 2018 – September 30, 2020
Funding Type: Lab Award
Maldistribution of refrigerant in heat exchangers is known to reduce their performance. In the proposed technology, piezoelectric sensor-actuators are integrated directly into the heat exchanger headers to simultaneously sense maldistribution and actuate the flow in real time to compensate.
Current methods of addressing geometry-induced flow maldistribution in heat exchangers involve a costly redesign process of headers and tubes. Such procedures have limited impact for particular operating conditions; this project provides an effective solution with real-time response capability and can potentially be retrofitted into existing heat exchanger designs.
This project will reduce the refrigerant-side pressure drop, increase heat transfer effectiveness, capacity and the overall system COP by:
- Modeling of flow distribution in heat exchanger tubes with closed-loop feedback control of sensor-actuators and using results to identify piezoelectric transducers capable of simultaneous sensing and actuation
- Performing detailed experiments on a custom-fabricated transparent heat exchanger with integrated piezoelectric sensor-actuators and artificial geometry-induced maldistribution
This project addresses a challenging problem by providing real-time flow distribution control that could not be resolved by previous static solutions with limited applicability. When successfully implemented in heat exchanger designs currently used for residential HVAC (for example) with 10% improvement in system COP, primary energy savings technical potential will be 225 TBtu for the 2030 energy market in all climate zones.
DOE Technology Manager: Antonio Bouza
Lead Performer: Viral K. Patel, Oak Ridge National Laboratory