Temperature Measurements On The SVT System Test Ladder

C.J. Liaw (July 98)

The attached nine figures show the equipment used for temperature studies during the SVT ladder system test, plus the obtained results. The measurement results include the calibrations of the IR sensor (used to perform the measurements), the temperatures on the detectors versus air flow rates and water flow rates, the temperature gradients across the detectors versus air flow rates and water flow rates, and the maximum temperatures on the PASA versus water flow rates. The calibrated IR sensor(a K type thermocouple), was located about 5 mm above the detector or the PASA during the measurements. There were nine equally spaced measurement locations on each detector (one at the center, four at the corners and four at the center of the sides). The temperature gradient of each detector is defined as the difference between the maximum and the minimum temperature of the nine points. The measurement location on the PASA was at the middle of the hybrid.
The results show that:

1. The accuracy of the IR sensor is within +/- 0.1 oC.

2. The detector temperatures, at the designed air and water flow rates, are between 21.8 and 22.5 oC with the maximum in the middle of the ladder between detectors #2 and #3 (as expected).

3. The temperature gradients varied between 0.28 to 0.58 oC (the ANSYS prediction was 0.4 oC).

4. The maximum temperature on the PASA varied from 25 oC to 26.3 oC (compared to 25.6 oC from ANSYS).

The following pictures are in JPG format. Size differs between 0.4 and 4 MByte.
Temperature test setup Close-up of air cooling and water cooling system
Calibration curve for IR temperature sensor on detector
Calibration curve for IR temperature sensor on PASA
Temperatures along centerline of all four detectors vs. air flow rate
Temperatures along centerline of all four detectors vs. water flow rate
Temperature gradient on a detector vs. air flow rate
Temperature gradient on a detector vs. water flow rate
Maximum temperatures on Hybrids vs. water flow rates