TURBINE & COOLING SYSTEM

Presented By – AVIJEET PRATAP 07ME12 IET AGRA

DEFINITION

A Turbine is a Form of Engine Requires a suitable working fluid in order to function- a source of High Grade Energy and a Sink for Low Grade energy. When a Fluid Flows through the Turbine ,Part of Energy Content is Continuously Extracted and Converted in to Useful mechanical Work.

PRICIPLE OF STEAM TURBINE

Steam turbine depends completely upon the dynamic action of the steam. According to Newton’s second law of motion, the FORCE is proportional to the rate of change of MOMENTUM (mass x velocity). If the rate of change of momentum is caused in the steam by allowing a high velocity jet of steam to pass over curved blade, the steam will impart a force to the blade. If the blade is free, it will free off (rotate) in the direction of force.

mc1 Moving Blade Force = mc1 - mc2 mc2 The steam from the boiler is expanded in a passage or nozzle , where due to fall in pressure of steam is converted into Kinetic energy of steam & this KE of steam is converted into work moving blade

TYPES OF TURBINE

On the basis of principle of operation Impulse turbine Reaction turbine Impulse- Reaction turbine Impulse Turbine .. In impulse the drop in pressure of steam takes place only in nozzle & not in moving blades. This is obtained by making the blade passage of constant cross section area it may be noted that energy transformation takes place only in nozzles. Moving blades only cause energy transfer.

X X X

Reaction turbine: Pressure drop take place in rotor (M.B.). Energy transformation takes place in rotor. Energy transfer only in rotor.

Impulse- Reaction turbine: In this turbine drop in pressure of steam takes place in fixed blade as well as moving blade. It may be noted that energy transformation occur in both fixed blade & moving blade. The rotor blade cause energy transfer & energy transformation.

COMPOUNDING

Compounding of Impulse turbine : One row of nozzles followed by one row of blades is called a stage of turbines. Compounding is a method for reducing the rotational speed of the impulse turbine to practical limit. Boiler pressure down to condenser pressure in a single stages so high RPM & large diameter of turbine.

Three type of compounding

Pressure compounding Velocity compounding Pr & velocity compounding

STEAM SUPPLY HP IP CRH HRH BOILER LP-A LP-B CONDENSER CONDENSER G ~

CROSS SECTIONAL VIEW OF TURBINE

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COOLING SYSTEM

CIRCULATING WATER SYSTEM

INTRODUCTION . Circulating Water system supplies cooling water to the turbine condenser. .

• It is used to maintain the vacuum in the condenser.

Types of Circulating water system

1. Open or Once Through It is used when there is a large source of water available.

e.g.- river , ocean.

2. Closed Cooling system In this system, warm water from condenser is passed through a cooling device, like cooling tower.

CW Pump Exhaust Stem from Turbine Condenser Filter Condensate Condensate Pump Hot water River

Open or Once Through

Exhaust Stem from Turbine Condenser Cooling water Condensate to boiler Hot water Condensate Pump Hot air Cooling Tower CW Pump

Closed Cooling system

Make up water from river

Cooling tower

• It cools the warm water discharged from the condenser & feed the cool water back to the condenser. • It reduces the cooling water demand in the power plant.

Types of cooling tower

1. Natural Draught Cooling Tower 2. Mechanical Draught Cooling Tower A. Forced Draught Cooling Tower B. Induced Draught Cooling Tower

Losses in cooling tower 1. Evaporation Losses 2. Drift Losses 3. Blowdown Losses

2 May 2020

LUBE OIL SYSTEM

TURBINE LUBE OIL SYSTEM

1.FLOW DIAGRAM OF LUBE OIL SYSTEM 2.NECESSITY OF LUBE OIL SYSTEM 3.COMPONENTS OF LUBE OIL SYSTEM 4.FUNCTIONS OF INDIVIDUAL COMPONENTS OIL 5.FLOW TO DIFFERENT BRANCHES 6.FIRE PROTECTIONS

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Lubrication :

To supplies oil to the bearing to form a film of oil as the shaft rotates.

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Temperature control :

To maintain temperature of the bearing.

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Sealing medium :

To the prevent H 2 leak out along the Generator shaft.

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Jacking of shaft :

Supply to jacking device.

2 May 2020

COMPONENTS OF LUBE OIL SYSTEM

The system mainly consists of Main oil pump, BOP, main oil tank, AC lubricant pump, DC emergency oil pump,MSP, spill valve, oil cooler, Transfer valve, oil smoke separator, shaft jacking up device, oil hydrogen separator, oil level indicator as well as connecting lines, monitoring instruments, etc.

• • • • • • • • The oil tank adopts a combination mode as various devices allocated on the tank as

AC lube oil pump, DC emergency oil pump, Oil smoke separator, Oil level indicator, Electric heater, Spill valve, BOP MSP

2 May 2020

SEAL OIL SYSTEM

INTRODUCTION Hydrogen is used for the cooling of generator rotor. Hydrogen is so much explosive when it come into contact with air . To save this hydrogen from explosion we need sealing of this hydrogen. For this purpose we generally use oil. This sealing is very much similar to sealing of the pump on its gland.

The functions of the seal oil control system

• • Providing seal oil to a sealing continuously Prevent the escape of hydrogen gas from the generator at the point of rotor exit . A continuous film between the rotor collar and seal liner is maintaining by means of oil at a pressure which is slightly above then hydrogen pressure.

STATOR WATER COOLING SYSTEM

FUNCTION The Stator Coil Cooling Water System main function is to guarantee cooling water uninterrupted flow into stator coil. At the same time, the system also must control enter the stator coil water pressure , flow, temperature, conductivity

System consists of 2 Motor driven pumps, 2 Coolers, 2 Filters and 1 mixed Bed type Ion Exchanger.

EE OF Gen.

Teflon tubes Winding TE of Gen Hot water output to Expansion tank Expansion tank Cold water enter Generator Turbine end Excitation End