Turbine flow meter

Turbine flowmeters use a free-spinning turbine wheel to measure fluid velocity, much like a miniature windmill installed in the flow stream. The fundamental design goal of a turbine flowmeter is to make the turbine element as free-spinning as possible, so no torque will be required to sustain...
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Hydraulic system

Given the ability of pressurized fluids to transmit force over long distances, it is not surprising that many practical “fluid power systems” have been built using fluid as a mechanical power-conducting media. Fluid systems may be broadly grouped into pneumatic (gas, usually air) and hydraulic (liquid, usually oil)....
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2 wire transmitter current loop

It is possible to convey electrical power and communicate analog information over the same two wires using 4 to 20 milliamps DC, if we design the transmitter to be loop-powered. A loop-powered transmitter connects to a process controller in the following manner: Here, the transmitter...
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Volumetric flow calculations

we may derive a relatively simple equation for predicting flow through a fluid-accelerating element given the pressure drop generated by that element and the density of the fluid flowing through it: This equation is a simplified version of the one derived from the physical construction of a...
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Rotameters

The simplest example of a variable-area flowmeter is the rotameter, which uses a solid object (called a plummet or float) as a flow indicator, suspended in the midst of a tapered tube: As fluid flows upward through the tube, a pressure differential develops across the plummet....
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