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Hydraulic machines
Chapter one: Introudction
Eng. Laith Batarseh
Introduction
Turbo machines used to transfer energy from or to continuous fluid flow by means
of rotating parts
Turbo machines
Work done by fluid Work done on fluid
Turbine Pump,
compressor
and fan
1.1. Basic Concepts
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Introduction
Fluid energy
Incompressible fluid
Compressible fluid
Pressure Enthalpy
Introduction
• Examples
Pelton wheel Francis turbine Kaplan turbine
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Introduction
• Examples
centrifugal pump impeller reciprocating pump
Introduction
Outlet flow
Axial
Radial
Mixed
the path of the through-flow is wholly or mainly parallel to the axis of rotation
the path of the through-flow is wholly or mainly in a plane perpendicular to the
rotation axis
the direction of the through-flow at rotor
outlet when both radial and axial velocity
components are present in significant
amounts
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Introduction
• Control Volume
Introduction
• Linear Momentum Equation
Where:
Fx is the force component in x-direction
Fpx represents the pressure force component in x-direction
Fsx represents the shear force component in x-direction
Fbx represents the body force component in x-direction
Mx is the momentum flux in x-direction = ρQVx.
1.1,,
inxoutxcvxbxsxpxx MMM
tFFFF
1.2. Free jets
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Introduction
• For steady state flow case, linear momentum equation
become
• Similar momentum equations are applicable to
other coordinate directions y and z.
2.1
,,
inxoutx
inxoutxbxsxpxx
QVQV
MMFFFF
Introduction
Free jets
Case1: jet on Stationary Plate
Assume:
1. The flow is open to atmospheric
2. No friction between fluid and plate
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Introduction
Case2: jet on Movable Plate
Introduction
Case2: jet on Movable Plate
power transmitted to the plate (P)
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Introduction
Example 1.1
Problem statement
Introduction
Example 1.1
Solution
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Introduction
Example 1.1
Solution (a)
Introduction
Example 1.1
Solution (b)
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Introduction
Example 1.2
Problem statement
Introduction
Example 1.2
Solution
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Introduction Example 1.2
Solution
Introduction
Example 1.2
Solution
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Introduction
Example 1.2
Solution
Introduction
Example 1.3
Problem statement
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Introduction
Example 1.3
Solution
Introduction
Example 1.3
Solution
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Introduction
Example 1.3
Solution
Introduction
Example 1.3
Solution
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Introduction
Case3: Jet impingement on a set of flat plates mounted on a wheel
when all the plates on the wheel are
considered, one or other vanes will
intercept all the flow from the jet. Thus,
the entire discharge issuing out of the
jet is involved in the transfer of power
to the wheel. While the relative velocity
of plates is still (V – u), the total
discharge Q (= AV) is involved in the
momentum flux undergoing the
change and not the relative discharge
Qr
Introduction
Case3: Jet impingement on a set of flat plates mounted on a wheel
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Introduction
Case4: Jet Impingement on a Stationary Curved Plate
Introduction
Case4: Jet Impingement on a Stationary Curved Plate
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Introduction
Case5:Jet Impingement on a Single Moving Symmetric Curved Plate
Introduction
Case5:Jet Impingement on a Single Moving Symmetric Curved Plate
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Introduction
Case5:Jet Impingement on a Single Moving Symmetric Curved Plate
Introduction Example 1.4
Problem statement
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Introduction solution
Introduction solution
Study example 1.5
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Introduction Example 1.6
Problem statement
Introduction Solution
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Introduction Solution
Introduction
Case6: Jet impingement on a Series of Curved Vanes Mounted on a Wheel
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Introduction
Case6: Jet impingement on a Series of Curved Vanes Mounted on a Wheel
Introduction
Case6: Jet impingement on a Series of Curved Vanes Mounted on a Wheel
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Introduction
Velocity Triangles
Introduction
1.3. Velocity Triangles
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Introduction
Other cases
1.3. Velocity Triangles
Introduction
Velocity Triangles
Mo
vin
g b
lad
e
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Introduction
Velocity Triangles
α < 90o
Introduction
Velocity Triangles
α = 90o
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Introduction
Velocity Triangles
α > 90o
Introduction Example 1.10
Problem statement
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Introduction Example 1.10
Solution
Introduction Example 1.10
Solution
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Introduction Example 1.10
Solution
Introduction Example 1.12
Problem statement
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Introduction Example 1.12
Solution
Introduction Example 1.12
Solution
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Introduction Example 1.12
Solution
Introduction Example 1.12
Solution
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Introduction
1.7. classification of hydraulic turbines
Interaction with
water flow
Impact Reaction
No pressure change at the
rotor (i.e. jet impact occurs at
atmospheric pressure)
Examples: Pelton wheel
pressure changes at the rotor
(i.e. jet impact occurs in cased
machine)
Examples: Francis and Kaplan
turbine s
Introduction
1.7. 1classification of hydraulic turbines
Head
High head
H> 400m
Low head
3m<H<60m
Medium head
60m<H<400m
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Introduction
1.7.2. turbine Efficiencies
Introduction
1.7.2. turbine Efficiencies
1. Volumetric Eficiency, ηv
2. Hydraulic Eficiency, ηh
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Introduction
1.7.2. turbine Efficiencies
3. Mechanical Eficiency, ηm
4. Overall Eficiency, ηo
Introduction
1.7.2. turbine Efficiencies
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Introduction
1.8. similarity ratios
Introduction
1.8. 5. Similarity Ratios of Turbinebsy Dimensionanl Aalysis
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Introduction
1.8. 5. Similarity Ratios of Turbinebsy Dimensionanl Aalysis
Reynolds number
Introduction
1.8. 5. Similarity Ratios of Turbinebsy Dimensionanl Aalysis
Assume the effect Reynolds number is neglected
1.8. 6. Specific Quantities
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Introduction
1.8. 6. Specific Quantities
Introduction
1.8. 6. Specific Quantities
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Introduction
Introduction
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Introduction
Introduction
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Introduction
Introduction
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Introduction
Introduction
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Introduction
Introduction