MHD Power generation

MHD Power Geneartion

1. Presented By:
PATEL YASH S. (150123119039)
Branch:- Mechanical
Semester:-8
th
(D)
Subject:-Renewable Energy Engineering(2181910)
Active Learning Assignment (ALA)
Topic:-MHD Power Generation
03/18/18
1
GANDHINAGAR INSTITUTE OF
TECHNOLOGY
MECH 8 D3 REE

2. Content
Introduction
Principle of MHD Power Generation
Method of MHD Power Generation
Open cycle system
Closed cycle system
Advantages
disadvantages
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3. Introduction
Magneto hydro dynamic (MHD) principle is applied for
generating power from coal fired or reactor power plants.
 MHD generator plant does not require any turbine and does
not have any generator shaft. In a MHD generator the
thermal energy is directly converted to electrical energy.
MHD generator is a heat engine operating on turbine cycle
and transforming the internal energy of gas directly into
electrical energy.
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4. PRINCIPLE
 Faraday’s Law of Electromagnetic Induction:- When an
electric conductor moves across a magnetic field, a voltage is
induced in it, which produces an electric current .
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5. METHODS OF MHD
POWER GENERATION
Open cycle system
Closed cycle system
1.Seeded inert gas MHD generator
2.Liquid metal MHD system
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6. Open cycle system
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MECH 8 D3 REE

7. Open cycle System
Fossil fuel (coal) is burnt to very high temperature in the
furnace to very high temperature to achieve ionized gas. The
electrical conductivity of the plasma is increased by seeding
the gas by addition of potassium or cesium. High
conductivity plasma is accelerated through the MHD tunnel
convergent-divergent portion of the nozzle shaped tunnel.
The pressure ratio (P1/P2) from high pressure side to low
pressure side to nozzle throat is so high and angle of
divergence of tunnel is such that very high gas velocity is
achieved in divergent portion. Conductive gas passes
through the magnetic field B of the MHD generator.
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8. Open cycle system
The MHD generator delivers DC electric power through its electrode
system. Heat from hot exhaust gases can be recovered further in the
heat recovery chamber. Heat is supplied to heat exchanger to
produce steam for steam turbine which drives auxiliary generator.
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9. Closed cycle system
•Two general types of closed cycle MHD generators are being
investigated.
• Electrical conductivity is maintained in the working fluid by
ionization of a seeded material, as in open cycle system.
•A liquid metal provides the conductivity.
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10. Closed cycle system
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11. Closed cycle system
Two working fluids are used, one for liquid metal & the other
for inert gases.
Liquid metal is heated by coal fired plant or nuclear reactor
plant. Heating by liquid metal causes the expansion of inert
gases.
 The mixture of inert gas & liquid metal is passed through
MHD tunnel.
The gas expanding in the tunnel gets accelerated & increases
the velocity of the mixture.
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12. Closed cycle system
The liquid metal acts as a moving conductor in the tunnel.
After passing through the MHD generator, the two fluids are
separated again. The liquid metal is reheated. The gas is
cooled & recompressed. Both the working fluids are re-
circulated again.
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13. Advantages
MHD-steam hybrid plant is efficient as around 50-60%.
This system have no moving part.
This system more reliable
It has ability to reach the full power level instantly.
Maintenance cost is low.
Cost of power generation per unit is less.
Coal,oil,solar,nuclear can be used with the MHD generator.
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14. Disadvantages
MHD equipments have shorter life due to high temperature
stresses.
It has high fluid friction losses and heat transfer losses.
It has very high operating temperature, which restrict the
choice of material for various equipments.
There are technical limitation on enhancing the fluid
conductivity and strength of the magnetic field.
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15. 03/18/18 15
Thank You…Thank You…
MECH 8 D3 REE