Wide-Temperature Electronically Scanned Pressure Measurement Module

Wide-temperature electronically scanned pressure (ESP) measurement modules have been developed for windtunnelapplicationsforserviceovera widetemperaturerange[50 ±C(122±F)toi175±C(i283±F)].Thesemodules are designed to account for offset voltage drift, operate without thermal protection in cryogenic temperature environments,andmaintainastablecalibrationformonths.ConventionalESPmodulescannotoperateincryogenic environments without thermal protection, for example, a heater box, which reduces available space for module installation, demands labor-intensive and time-consuming installation, and requires heavy electrical wiring that can shunt the wind-tunnel force balance. To account for force-balance shunting, separate wind-tunnel tests must be conducted to collect pressure and force-balance measurements, which devour both time and money. Because of offset voltage drift, conventional modules also require frequent test interruptions for online calibration, which can consume as much as 15% of total test time. Wide-temperature ESP modules eliminate these shortcomings while providing total uncertainty in pressure measurement less than 0.1% of full-scale output. Design, fabrication, and calibration of these modules are described. Test results from data gathered using two 16-port wide-temperature modules in the National Transonic Facility wind tunnel at NASA Langley Research Center are also provided.