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Pressure Measurement. PressurePressure = Force/Area Units of force per unit areaPressure measurements.All pressure measurements are relative measurements.The measurement of a pressure at a point is relative to, or referred to, a reference pressure.. Pressure References. Absolute Pressure
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1. Lecture 11 Pressure Measurements
Techniques to measure pressure.
2. Pressure Measurement Pressure
Pressure = Force/Area
Units of force per unit area
Pressure measurements.
All pressure measurements are relative measurements.
The measurement of a pressure at a point is relative to, or referred to, a reference pressure.
3. Pressure References Absolute Pressure:
Measured relative to a zero pressure or a perfect vacuum.
Gauge Pressure:
Measured relative to the local ambient pressure.
Differential Pressure:
Measured pressure between two point.
4. Barometer Aneroid from Greek aneros not wet
5. Mercury Barometer Measurement of Atmospheric Pressure
6. Manometers Manometers are one of the oldest pressure measuring devices.
7. How could you make a U-tube manometer more sensitive? Change Manometer fluid.
Incline the manometer.
Combine inclined and straight sections.
8. Inclined Manometer
9. Pressure Transducers What is a pressure transducer?
A pressure transducer is a device that converts a pressure signal to an electric signal.
What type of devices can be used to create a pressure transducer?
Strain gage devices
Capacitance devices
Piezoelectric devices
10. Pressure TransducerStrain gage device
11. Pressure Transducer Capacitance device
12. Pressure Transducer Piezoelectric device
13. Pressure Sensitive Paint
14. Pressure Probes to Measure Velocity Pitot Static Probe
15. Measuring Velocity Components Five hole Pressure Probe
16. Pressure Models Airfoils, wings and complete airplane models equipped with pressure ports can be used to determine model loads and load distribution.
Pressure models provide more detail on how the loads are generated than a force balance.
Disadvantage is pressure measurement of model forces is more time consuming.
17. How to you create a pressure model? Suppose you have designed a new airfoil section and you want to determine its aerodynamic performance and its pressure distribution, how would make such a model?