external combustion engine

START WITH THE NAME OF ALLAH INSTRUCTAR NAME:SIR ALI SHAHBAZ AND GROUP MEMBER IS :

START WITH THE NAME OF ALLAH INSTRUCTAR NAME:SIR ALI SHAHBAZ AND GROUP MEMBER IS PRESENTED BY (i) MUHAMMAD ABDULLAH (ii) KAHSIF HAMZA (iii) MUHAMMAD TAHIR THE UNIVERSITY OF LAHORE

External combustion engine :

External combustion engine

External combustion engine :

External combustion engine An external combustion engine (EC engine) is a heat engine which ignition  occurs outside the chamber (cylinder or turbine) in which heat is converted to  mechanical energy, e.g. a steam Engine.

Slide 4:

steam engine A steam engine is a heat engine that performs mechanical work using steam as its working fluid. Steam engines are typically external combustion engines, where heat is supplied to the working fluid from fuel burned outside the engine

Diagram of steam engine :

Diagram of steam engine

Classification of steam engines:

Classification of steam engines 1.According to number of working strokes Single acting steam engine Double acting steam engine 2.According to the position of the cylinder Horizontal steam engine. Vertical steam engine

Classification of steam engines (continuous):

Classification of steam engines (continuous) 3.According to the speed of the crankshaft Slow speed steam engine (less then100 r.p.m ). Medium speed steam engine(100 to 250 r.p.m ). High seep steam engine (above to 250 r.p.m ).

Classification of steam engines (continuous):

Classification of steam engines (continuous) 4.According to the type of exhaust Condensing steam engine. Non-condensing steam engine. 5.According to the expansion of the steam in the engine cylinder. Simple steam engine Compound steam engine

Importance parts of a steam engine:

Importance parts of a steam engine Frame Cylinder Steam chest D-slide valve Inlet and exhaust ports Piston Piston rod

Importance parts of a steam engine (cont….):

Importance parts of a steam engine (cont….) (8) Cross-head (9) Connecting rod (10) Crank shaft (11) eccentric (12) eccentric rod and valve rod (13) Flywheel (14) Government

Working of a single cylinder double acting horizontal reciprocation steam engine :

Working of a single cylinder double acting horizontal reciprocation steam engine

The steam cycle :

The steam cycle The Rankine cycle is the fundamental thermodynamic of the steam engine. The Rankine cycle is a cycle that converts heat into work. The heat is supplied externally to a closed loop, which in steam engines contains water and steam. This cycle generates about 80% of all electric power used throughout the world.

Rankine Cycle:

Rankine Cycle Physical layout of the four main devices used in the Rankine cycle. Other components that perform the same or similar functions are often used, the turbine is often replaced with a steam driven piston.

Rankine Cycle:

Rankine Cycle Process 1-2 : The working fluid is pumped from low to high pressure, as the fluid is a liquid at this stage the pump requires little input energy. Process 2-3 : The high pressure liquid enters a boiler where it is heated at constant pressure by an external heat source to become a dry saturated vapor. Process 3-4 : The dry saturated vapor expands through a engine, generating power. This decreases the temperature and pressure of the vapor, and some condensation may occur. Process 4-1 : The wet vapor then enters a condenser where it is condensed at a constant pressure and temperature to become a saturated liquid. The pressure and temperature of the condenser is fixed by the temperature of the cooling coils as the fluid is undergoing a phase-change.

Applications of Steam engine :

Applications of Steam engine Steam power engines when attached to generator are able to produce electricity. It could be used at household level or industrial level depends upon the size of the steam engine. Steam boats are also designed to utilize steam power. Factories are run by steam power engines. Locomotives are steam power-driven.

Stirling engine :

Stirling engine

Slide 18:

A Stirling engine is a heat engine operating by cyclic compression and expansion of air or other gas, the working fluid , at different temperature levels such that there is a net conversion of heat energy to mechanical work. [1]

Functional description :

Functional description The engine is designed so that the working gas is generally compressed in the colder portion of the engine and expanded in the hotter portion resulting in a net conversion of heat into work. [2 ] An internal Regenerative heat exchanger increases the Stirling engine's thermal efficiency compared to simpler hot air engines lacking this feature.

Key components :

Key components Heat source Heater / hot side heat exchanger Regenerator Cooler / cold side heat exchanger Heat sink Displacer

Applications :

Applications Applications of the Stirling engine range from heating and cooling to underwater power systems. A Stirling engine can function in reverse as a heat pump for heating or cooling. Other uses include: combined heat and power, solar power generation, Stirling cryocoolers , heat pump, marine engines, and low temperature difference engines

Nuclear power:

Nuclear power

What is nuclear power?:

What is nuclear power? Nuclear power is energy which is produced with the use of a controlled nuclear reaction. Many nations use nuclear power plants to generate electricity for both civilian and military use, and some nations also utilize nuclear power to run parts of their naval fleets, especially submarines

Nuclear Energy:

Nuclear Energy The nucleus of an atom is the source of nuclear energy.

Nuclear Energy:

Nuclear Energy When the nucleus splits (fission), nuclear energy is released in the form of heat energy and light energy. Nuclear energy is also released when nuclei collide at high speeds and join (fuse).

Nuclear Energy:

Nuclear Energy The sun’s energy is produced from a nuclear fusion reaction in which hydrogen nuclei fuse to form helium nuclei .

Nuclear Energy:

Nuclear Energy Nuclear energy is the most concentrated form of energy . Most of us live within 10 miles of the Surry Nuclear Power Plant which converts nuclear energy into electromagnetic energy

Working cycle:

Working cycle Rankine cycle The four processes in the Rankine cycle Process 1-2 : The working fluid is pumped from low to high pressure, as the fluid is a liquid at this stage the pump requires little input energy. Process 2-3 : The high pressure liquid enters a boiler where it is heated at constant pressure by an external heat source to become a dry saturated vapor

Slide 30:

Process 3-4 : The dry saturated vapor expands through a turbine, generating power. This decreases the temperature and pressure of the vapor, and some condensation may occur Process 4-1 : The wet vapor then enters a condenser where it is condensed at a constant pressure to become a saturated liquid.

Two Connections:

Two Connections The input connection Into the reactor: fuel “ enrichment ” The output connection Out of the reactor: plutonium

Slide 33:

the input connection “ enrichment ”

“Enrichment”:

“ Enrichment ” Not about money, but about getting more U235 atoms in the uranium mix.

Enrichment: What?:

Enrichment : What? LEU Low Enriched Uranium Reactor fuel not much U235 can’t explode HEU Highly Enriched Uranium Explodes! weapons usable

the input Connection:

the input Connection Enrichment technology can produce reactor fuel or nuclear weapons material.

the output Connection:

the output Connection When the chain reaction inside the reactor wears out, the old LEU fuel is removed as waste and replaced with fresh fuel. The now highly radioactive old fuel is called spent fuel . Uranium in the fuel has been changed to Plutonium during the chain reaction that produced the heat to boil the water and make electricity.

Plutonium:

Plutonium Doesn’t occur in nature. Human-made in nuclear reactors. Good for nuclear weapons - Explodes Nagasaki, Japan

Good news about Plutonium:

Good news about Plutonium Extracting the plutonium from spent fuel is difficult and very dangerous because spent fuel is deadly radioactive Plutonium weapons are much harder to construct than HEU weapons

Nuclear Power is:

Nuclear Power is Unnecessary Expensive Dangerous Produces radioactive waste that will be dangerous for hundreds of thousands of years Always connected to nuclear weapons