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Combustion Research Associates manufactures differential producer type flow
meters for gas and liquid flow measurement.
WORKING PRINCIPLE OF FLOWMETER
The
flow-meter offered is differential producing flow-meter and is most
widely used in industry for flow measurement applications.
The
meter consists of three separate major devices that act on combination
to measure the flowrate. The first device is differential producer, a
PRIMARY device called VENTURI or ORIFICE PLATE which generates
differential pressure proportional to flowrate. The second device is
DIFFERENTIAL PRESSURE TRANSMITTER, which measures this pressure and
generates signal, which is proportional to the flowrate. The third
device is the rate indicator and recorder (optional) which gives the
flowrate and totalised flow in desired engineering unit.
BASIC PRINCIPLE
The
underlying principle of all differential -producing flowmeters is
Bernaulli's streamline energy equation. When the flow is contracted,
either gradually or abruptly, kinetic energy increases increases at the
expense of available potential energy (static pressure). tHe pressure
diffence between the taps located at the full pipe section and and in
the vicinity of contraction is related to the square of the velocity
at section 2, fluid properties and to the abruptness of contraction.
Since the velocity times the pipe area is volumetric flowrate, the
basic flow equation may be written as a squre-root relation ship among
measured differential pressure hw, density p and flowrate Q as
Q = Fmc [ hw /p]1/2
The
meter constant Fmc adjusts for dimensional units and includes a
discharge coefficient that corrects for contraction characteristics,
pressure tap location, and velocity profile [Reynolds number].
Combustion
Research Associates manufactures orifice plate, venture, flow limiting
nozzles as per approved international standards.
Materials chosen are compatible to the medium of flow.
FEATURES
As per international design
Venturi are energy saving due to p
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