ZM9101C Venturi Meter Setup Teaching Equipment Hydrology Demonstrators
(I) Experiment purpose
1.To understand Venturi meter and orifice plate flowmeter experiment set and principle.
2.Draw pressure difference and flow relationship curve, confirm Venturi meter and orifice plate flowmeter discharge coefficientμ value.
(II) Experiment principle
Venturi meter is widely applied in normal flowmeter in industrial tube, it contains three parts: contraction section, venturi, diffuser. Due to water section constriction, venturi active cross-section water flow energy increase, potential energy decrease, lead to contraction section front and back section pressure difference, and generate bigger potential energy difference, this potential energy difference can be calculated by differential pressure gauge.
Orifice plate flowmeter principle is the same as Venturi meter, according to energy equation and barometric surface principle will get the head loss Venturi meter(orifice plate flowmeter) flow equation Regardless of the head loss:
For Venturi meter:
For orifice plate flowmeter:
According to experiment equipment conditioner, the tube real measured value Qreal can be measured by volumetric method or by electronics flow meter.
In real liquid flow, due to the existence of the resistance, water flow through Venturi meter(or orifice plate flowmeter) will get energy loss, so the real flow Qreal will be smaller than Qideal, so in real application, it should be amended, real measured flow and ideal liquid condition flow ratio is called discharge coefficient, so