2. ContentsContents
1.1. IntroductionIntroduction
2.2. Need of MHDsNeed of MHDs
3.3. Principle Of MHD Power GenerationPrinciple Of MHD Power Generation
4.4. Comparison b/w a Turbo generator and aComparison b/w a Turbo generator and a
MHD generatorMHD generator
5.5. Types of MHD SYSTEMTypes of MHD SYSTEM
6.6. Difference between Open Cycle andDifference between Open Cycle and
Closed Cycle MHD SystemClosed Cycle MHD System
7.7. Advantages OF MHD SystemAdvantages OF MHD System
8.8. Disadvantages of MHD SystemDisadvantages of MHD System
9.9. ApplicationsApplications
10.10. ConclusionConclusion
3. IntroductionIntroduction
Magneto HydroDynamic (MHD) system is a non-Magneto HydroDynamic (MHD) system is a non-
conventional source of energy which is based uponconventional source of energy which is based upon
Faraday’s Law of Electromagnetic Induction, whichFaraday’s Law of Electromagnetic Induction, which
states that energy is generated due to the movement ofstates that energy is generated due to the movement of
an electric conductor inside a magnetic field.an electric conductor inside a magnetic field.
4. Concept given by Michael Faraday in
1832 for the first time.
MHD System widely used in advanced
countries.
Under construction in INDIA.
5. Need of MHDsNeed of MHDs
At present a plenty of energy is needed toAt present a plenty of energy is needed to
sustain industrial and agricultural production,sustain industrial and agricultural production,
and the existing conventional energy sourcesand the existing conventional energy sources
like coal, oil, uranium etc are not adequate tolike coal, oil, uranium etc are not adequate to
meet the ever increasing energy demands.meet the ever increasing energy demands.
Consequently, efforts have been made forConsequently, efforts have been made for
harnessing energy from several non-harnessing energy from several non-
conventional energy sources likeconventional energy sources like MagnetoMagneto
Hydro Dynamics(MHD) System.Hydro Dynamics(MHD) System.
6. Principle Of MHD PowerPrinciple Of MHD Power
GenerationGeneration
Faraday’s law of electromagnetic inductionFaraday’s law of electromagnetic induction ::
When an electric conductor moves across a magnetic field, anWhen an electric conductor moves across a magnetic field, an
emf is induced in it, which produces an electric current .emf is induced in it, which produces an electric current .
7. Lorentz ForceLorentz Force on theon the
charged particle (vector),charged particle (vector),
F = q(v × B)F = q(v × B)
where,where,
v = velocity of the particlev = velocity of the particle
(vector)(vector)
q= charge of the particleq= charge of the particle
(scalar)(scalar)
B = magnetic field (vector)B = magnetic field (vector)
8. Comparison between a TurboComparison between a Turbo
generator and a MHD generatorgenerator and a MHD generator
9. Types ofTypes of
MHDMHD SYSTEMSYSTEM
(1)Open cycle System(1)Open cycle System
(2)Closed cycle System(2)Closed cycle System
(i)Seeded inert gas systems(i)Seeded inert gas systems
(ii) Liquid metal systems(ii) Liquid metal systems
10. DIFFERENCE BETWEEN OPENDIFFERENCE BETWEEN OPEN
CYCLE AND CLOSED CYCLECYCLE AND CLOSED CYCLE
SYSTEMSYSTEM
Open Cycle SystemOpen Cycle System
Working fluid after generatingWorking fluid after generating
electrical energy is dischargedelectrical energy is discharged
to the atmosphere through ato the atmosphere through a
stack .stack .
Operation of MHD generator isOperation of MHD generator is
done directly on combustiondone directly on combustion
products .products .
Temperature requirement :Temperature requirement :
2300˚C to 2700˚C.2300˚C to 2700˚C.
More developed.More developed.
Closed Cycle SystemClosed Cycle System
Working fluid is recycled to theWorking fluid is recycled to the
heat sources and thus is usedheat sources and thus is used
again.again.
Helium or argon(with cesiumHelium or argon(with cesium
seeding) is used as the workingseeding) is used as the working
fluid.fluid.
Temperature requirement : aboutTemperature requirement : about
530˚C.530˚C.
Less developed.Less developed.
11. NEED FOR FURTHERNEED FOR FURTHER
RESEARCHRESEARCH
The MHD channel operates on extreme conditions ofThe MHD channel operates on extreme conditions of
temperature, magnetic and electric fields .temperature, magnetic and electric fields .
So, numerous technological advancements are neededSo, numerous technological advancements are needed
prior to commercialization of MHD systems .prior to commercialization of MHD systems .
Search is on for better insulator and electrodeSearch is on for better insulator and electrode
materials which can with stand the electrical, thermal,materials which can with stand the electrical, thermal,
mechanical and thermo-chemical stresses andmechanical and thermo-chemical stresses and
corrosion.corrosion.
12. ADVANTAGES OFADVANTAGES OF
MHD SYSTEMMHD SYSTEM
Conversion efficiency of about 50% .Conversion efficiency of about 50% .
Less fuel consumption.Less fuel consumption.
Large amount of pollution free power generated .Large amount of pollution free power generated .
Ability to reach full power level as soon as started.Ability to reach full power level as soon as started.
Plant size is considerably smaller thanPlant size is considerably smaller than
conventional fossil fuel plants .conventional fossil fuel plants .
Less overall generation cost.Less overall generation cost.
No moving parts, so more reliable .No moving parts, so more reliable .
13. DISADVANTAGES OFDISADVANTAGES OF
MHD SYSTEMMHD SYSTEM
Suffers from reverse flow (short circuits) ofSuffers from reverse flow (short circuits) of
electrons through the conducting fluids around theelectrons through the conducting fluids around the
ends of the magnetic field.ends of the magnetic field.
Needs very large magnets and this is a majorNeeds very large magnets and this is a major
expense.expense.
High friction and heat transfer losses.High friction and heat transfer losses.
High operating temperature.High operating temperature.
Coal used as fuel poses problem of molten ashCoal used as fuel poses problem of molten ash
which may short circuit the electrodes. Hence, oilwhich may short circuit the electrodes. Hence, oil
or natural gas are much better fuels foror natural gas are much better fuels for
MHDs. Restriction on use of fuel makes theMHDs. Restriction on use of fuel makes the
operation more expensive.operation more expensive.
14. APPLICATIONSAPPLICATIONS
Power generation in space craft.Power generation in space craft.
Hypersonic wind tunnel experiments.Hypersonic wind tunnel experiments.
Defense application.Defense application.
15. CONCLUSIONCONCLUSION
The MHD power generation is in advanced stage todayThe MHD power generation is in advanced stage today
and closer to commercial utilization. Significant progressand closer to commercial utilization. Significant progress
has been made in development of all critical componentshas been made in development of all critical components
and sub system technologies. Coal burning MHDand sub system technologies. Coal burning MHD
combined steam power plant promises significantcombined steam power plant promises significant
economic and environmental advantages compared toeconomic and environmental advantages compared to
other coal burning power generation technologies. It willother coal burning power generation technologies. It will
not be long before the technological problem of MHDnot be long before the technological problem of MHD
systems will be overcame and MHD system wouldsystems will be overcame and MHD system would
transform itself from non- conventional to conventionaltransform itself from non- conventional to conventional
energy sources.energy sources.