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Fluid mechanics, Practical Applications.
- 1. VENTURIMETER & ORIFICE METER/ORIFICE PLATE PRACTICALAPPLICATIONS OF BERNOULLI’S EQUATION Name USN S P Amrutha Bindu 1BM22AS041 Sammith K 1BM22AS049 Samskruthi N M 1BM22AS050 Sushmitha K S 1BM22AS060
- 2. CONTENTS 1.VENTURIMETER 2. EXPRESSION FORRATE OF FLOW THROUGH VENTURIMETER 3. ORIFICE METER 4. COMPARISON BETWEEN VENTURIMETER AND ORIFICEMETER
- 3. VENTURIMETER • It isa device used to measure the rate of flow of a fluid flowing through a pipe. • It consists of 3 parts a. A short converging part b. Throat c. Diverging part.
- 4. Expression for rateof flow through venturi meter. • Consider a venturi meter fitted in a horizontal pipe through which a fluid is flowing. • Let d1 = diameter at inlet or at section (1) p1 = pressure at section (1) v1 = velocity of fluid at section (1) a1 = area at section (1) • And, d2, p2, v2, a2 are the corresponding values at section (2)
- 5. Venturi meter • ApplyingBernoulli’s equation at section (1) and (2), we get • As the pipe is horizontal, hence z1=z2
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- 7. Venturi meter Value of‘b’ given by differential U-tube manometer CASE 01: Let the differential manometer contains a liquid which is heavier that the liquid flowing through the pipe. Let Sh = Sp. Gravity of the heavier liquid So = Sp. Gravity of the liquid flowing through pipe x = Difference of the heavier liquid column in U-tube Then:
- 8. Venturi meter CASE 02.If the differential manometer contains a liquid which is lighter than the liquid flowing through the pipe, the value of h is given by Where: St = Sp. gr. of the lighter liquid in U-tube So = Sp. gr. of fluid flowing through the pipe x = Difference of the lighter liquid columns in U-tube
- 9. Venturi meter • CASE03. Inclined venturi meter with Differential U- Tube manometer. Case 01 and 02 are given for a horizontal venturi meter. This case is related to inclined venturi meter having differential U-tube manometer. Let the differential manometer contains heavier liquid then h is given as • CASE 04. Similarly, for inclined venturi meter in which differential manometer contains a liquid which is lighter than the liquid flowing through the pipe, the value of h is given as
- 10. ORIFICE METER/ORIFICE PLATE •It is a device used for measuring the rate of flow of a fluid through a pipe. • Cheaper device as compared to venturi meter. • Orifice- flat circular plate which has circular sharp edged hole, which is concentric with the pipe. • The orifice diameter is generally kept as 0.5 times the diameter of pipe, but it may vary from 0.4 to 0.8 times the pipe diameter.
- 11. Orifice meter • Adifferential manometer is connected at section (1), which is at a distance of about 1.5-2.0 times the pipe diameter upstream from the orifice plate, and at section (2) , which is at a distance of about half the diameter of the orifice on the downstream side from the orifice plate. • Let p1 = pressure at section (1) v1 = velocity at section (1) a1 = area of pipe at section (1) And, p2, v2, a2 are the corresponding values at section (2) Applying Bernoulli’s equation at sections (1) and (2), we get
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- 15. COMPARISON BETWEEN VENTURIMETER ANDORIFICEMETER Venturimeter • It has tapered structure which causes a gradual change in fluid velocity. • Pressure loss is less and its coefficient of discharge is high. • Expensive due to tapered structure of the pipe. • Suitable for fluids with high solid content. • The turn down ratio is about 10:1. Orificemeter • There is a sudden change in fluid velocity because of the flat flanges. • Pressure loss is more and its coefficient of discharge is low. • Cheaper due to simple structure of the pipe. • Suitable for clean fluids. • The turn down ratio is below 5:1.
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