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Jet ratio (m) is defined as the ratio of?
By BYJU'S Exam Prep
Updated on: September 25th, 2023
(A) Diameter of the jet of water to diameter of the Pelton wheel
(B) Velocity of the vane to velocity of the jet of water
(C) Velocity of flow to velocity of the jet of water
(D) Diameter of Pelton wheel to the diameter of the jet of water
Jet ratio (m) is the ratio of Diameter of Pelton wheel to the diameter of the jet of water. Jet ratio (m) is the ratio of the pitch circle diameter to the jet diameter. Jet ratio = diameter of wheel/ jet diameter, m = D/d.
Where, D is the Diameter of the pitch circle, d is the Diameter of the jet.
The value of m differs from, 11 ≤ m ≤ 15 ,
Number of vanes n = 15 + m/2, where m = jet ratio.
Difference Between Impulse Turbine and Reaction Turbine
We have elaborated on the difference between an Impulse and a Reaction turbine. You should go through the information mentioned in the table.
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Impulse turbine |
Reaction turbine |
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Kinetic energy is created from all hydraulic energy. |
Kinetic energy makes up a portion of hydraulic energy, while pressure energy makes up the remainder. |
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The atmosphere is still there everywhere. |
There is more pressure at the intake than the output. |
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Unneeded watertight casing |
The watertight casing needs to contain the runner. |
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Never install below the tailrace, and never use a draught tube |
Using a draught tube, it can be positioned above or below the tailrace. |
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The needle valve is used to control flow. |
A guide vane is used to control the flow of fluid. |
Summary:
Jet ratio (m) is defined as the ratio of? (A) Diameter of the jet of water to diameter of the Pelton wheel (B) Velocity of the vane to velocity of the jet of water (C) Velocity of flow to velocity of the jet of water (D) Diameter of Pelton wheel to the diameter of the jet of water.
The definition of jet ratio (m) is the ratio of the diameter of the water jet to the diameter of the Pelton wheel. For that, students can understand about the difference between two turbines from the table above.
