Thermal Vacuum Qualification Testing of the International Space Station Photovoltaic Radiators
The Photovoltaic Radiator (PVR) of the International Space Station (ISS) is a critical component of the Space Station’s thermal control system. It will cool the photovoltaic power system electronic equipment and the batteries used for power storage. The PVR will also provide environmental cooling for the service module during early phases of the Space Station. Prior to on-orbit operation, verification testing of the PVR was required to ensure the Orbital Replacement Unit (ORU) would operate as expected in the extreme on-orbit thermal environments. The on-orbit operational requirements included extreme thermal gradients, thermal cycles, and a range of coolant temperatures and flow rates, ORU pressure drop, deployment time, and electrical power consumption. The PVR ORU was tested in the world’s largest vacuum chamber at NASA Lewis Research Center’s (LeRC) Plum Brook Station Space Power Facility (SPF) located at Sandusky, Ohio.