Use fluid column heights to measure pressure differences.
U-tube manometers measure pressure differences by fluid column heights, ΔP=ρgΔh, with water, mercury or oil. Barometers measure atmospheric pressure. Bourdon gauges, diaphragm transducers and piezoresistive sensors are used for industrial measurement.
A 100 mm mercury difference equals 13.3 kPa.
Manometers measure pressure differences using fluid columns, which is a simple method used in labs and in duct and pipe testing.
Use fluid column heights to measure pressure differences.
Manometers measure pressure differences using fluid columns, which is a simple method used in labs and in duct and pipe testing.
A U-shaped tube filled with liquid, where the height difference gives the pressure difference between its two ends.
Water for low pressures, and mercury or special oils for higher pressures or more sensitive readings.
Typical applications include measuring the pressure drop across an orifice plate with a U-tube manometer, reading the draft in a chimney with an inclined manometer and checking the pressure of a gas line during commissioning.
Study "Fluid statics" first (topic 47 of 105 in Thermodynamics & Fluids). It covers the groundwork this topic builds on.
Multi-fluid manometer equation. Inclined tube for sensitivity. Sensor accuracy.
A 100 mm mercury difference equals 13.3 kPa.
The next topic is "Buoyancy", which builds directly on this one.
It is classed as Intermediate in Thermodynamics & Fluids (topic 48 of 105). It is an intermediate topic. Work through the beginner topics in Thermodynamics & Fluids first.
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