Pressure Temperature and Velocity

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Experiment 1: Pressure, Temperature, and Velocity Measurement Objective: The objective of this experiment is to determine the pressure and density of laboratory air, calibrate a pressure transducer and scannivalve, then determine the test section speed as a function of fan speed using three methods of velocity measurement. Equipment: Absolute pressure transducer, digital thermometer, pressure transducer (voltmeter), micromanometer, scannivalve, Pitot tube, low-speed wind tunnel. Part 1: Measurement of Atmospheric Pressure and Density 1. Read the barometer and wind-tunnel thermocouple. 2. Record the atmospheric pressure and wind-tunnel air temperature. 3. Record the estimated uncertainty for the readings taken. 4. Calculate the density of air inside the wind tunnel and uncertainty [kg/m3]. Part 2: Calibration of a Pressure Transducer and Scannivalve 1. Zero out the micromanometer and obtain its bias. Apply this bias to all micromanometer measurements. 2. Connect the micromanometer, pressure transducer (voltmeter), and scannivalve to the Pitot tube in the subsonic tunnel. 3. Record the readings of the three instruments at eight different speed settings of the tunnel: 15, 20, 25, 30, 35, 40, 45, & 50. 4. Plot two calibration curves with pressure transducer reading as the abscissa and micromanometer reading as the ordinate for the first, and micromanometer versus scannivalve as the second. Convert micromanometer data to read as total pressure in SI units [Pa]. 5. Compute a linear least-squares-fit of the calibration data and plot the resulting line on the same graph as the calibration data. Comment on the linearity of the pressure transducer and scannivalve. Part 3: Calibration of the Tunnel 1. Connect the micromanometer (calibrated in Part 2) across the wind-tunnel contraction in order to measure the static pressure drop. 2. Connect the