A venturi tube contains a throat that is smaller in diameter than the pipeline, into which it fits. The restriction diameter should not be less than 0.224 D and not more than 0.742 D where D is the nominal bore diameter of the pipe.
When the fluid flows through it, the pressure at the throat is lower than the upstream pressure (because of increased kinetic energy due to increased velocity, ½ mv2) and the consequent reduction in flow energy (Ef = P . v).
The flow rate is proportional to the pressure difference, P1 – P2.
where, k is dependent on the pipeline and throat diameter, density, and discharge coefficient
The venturi flow meter should always be used for turbulent flow. Its accuracy for a wide range of instruments is about 0.5%. ideal for use in Heat Ventilation Air Cond. (HVAC) applications, or air to furnaces and boilers and for liquids containing particles and slurries.
The Venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section (or choke) of a pipe. The Venturi effect is named after Giovanni Battista Venturi (1746–1822), an Italian physicist.
In fluid dynamics, a fluid’s velocity must increase as it passes through a constriction in accordance with the principle of mass continuity, while its static pressure must decrease in accordance with the principle of conservation of mechanical energy.
Thus any gain in kinetic energy a fluid may accrue due to its increased velocity through a constriction is balanced by a drop in pressure.
By measuring the change in pressure, the flow rate can be determined, as in various flow measurement devices such as venturi meters, venturi nozzles, and orifice plates.
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what is diffrence between hart protocol and field foundation please explain in detail
Hello, Differences already available in Communication Category. Pl check.
please explain about venturi installation , where taken out high pressure taping and low pressure taping and more detail