Question

What is the difference between venturimeter and orifice meter ?

Answer 1

A measuring instrument is a device that is used to determine the size of a physical quantity. Measurement is the process of acquiring and comparing physical quantities of real-world objects and events in the physical sciences, quality assurance, and engineering. As units, established standard items and events are utilised, and the measuring procedure yields a number that connects the item under investigation to the referred unit of measurement.

Complete answer:
The following are the differences between a venturi metre and an orifice metre.

Venturimeter	Orifice meter
The flow rate (discharge) in a pipe is measured using a venturimeter, which is a flow metre device or equipment. The Bernoulli theorem is utilised to operate the venturi metre, which is employed in the water supply business. Clemans Herchel, an American hydraulic engineer, created the venturi metre.	An orifice metre is a device that measures the rate of flow of a gas or fluid. An orifice plate, an orifice plate housing, and a metre tube are the essential components.
When a fluid runs through a restricted part (or choke) of a pipe, the Venturi effect occurs, resulting in a decrease in fluid pressure. The Venturi effect is named after Giovanni Battista Venturi, an Italian scientist who discovered it in the 18th century.	An orifice plate is a thin plate with a hole that is commonly used in pipes. When a fluid (whether liquid or gaseous) travels through an aperture, its pressure rises somewhat upstream, but as the fluid is pushed to converge to pass through the hole, the velocity rises and the fluid pressure falls.
In a venturi metre, the coefficient of discharge is 0.98, whereas in an orifice metre, it is 0.6. In a venturi metre, the turn down ratio is 10:1, but in an orifice metre, it is 5:1.	The orifice metre, on the other hand, is made up of a thin plate and a bore. The pressure loss in a venturi metre is 10%, whereas the pressure loss in an orifice metre is 50-60%.

According to the concept of mass continuity, an incompressible fluid's velocity must rise as it travels through a constriction, but its static pressure must drop according to the principle of mechanical energy conservation (Bernoulli's principle). As a result, any increase in kinetic energy gained by a fluid due to higher velocity due to a constriction is counterbalanced by a decrease in pressure.The cost of the venturi meter is more expensive than the orifice meter.

Note: The mechanisms by which these numerical relations are achieved are measuring instruments and formal test techniques that specify the instrument's usage. Instrument error and measurement uncertainty affect all measuring instruments to various degrees. Simple items like rulers and stopwatches to electron microscopes and particle accelerators are examples of these instruments. In the creation of contemporary measuring devices, virtual instrumentation is frequently employed.