fabrication of prototype of stirling engine
DESCRIPTION
This was the hardware project presentation prepared by our team on Stirling Engine during second year at VIT University Vellore. This was prototype of an SFA Stirling Engine.TRANSCRIPT
HARDWARE PROJECT
GUIDED BY :
Mr. V.G. SRIDHAR(SMBS)
TEAM MEMBERS: PRATEEK DEVAL(08BME163)
RAVI SHEKHAR (08BME181)
ASHISH DEVARTH (08BME037)
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.
The engine was first invented in 1816 by “ROBERT
STIRLING” so its name came to be stirling engine.
BASIC WORKING PRINCIPLE :
The main and the most basic principle underlying the working of a
Stirling engine is “DIFFERENCE OF TEMPERATURE ON TWO “DIFFERENCE OF TEMPERATURE ON TWO
SIDES OF CYLINDER OF THE STIRLING ENGINE”SIDES OF CYLINDER OF THE STIRLING ENGINE”
Every stirling engine has a sealed cylinder with one part hot and
the other cold.
The working gas inside the engine is moved by a mechanism from
the hot side to cold side.
When gas is on the hotter side it expands and pushes up on a
piston and vice-versa.
To understand the working of stirling engine and importance in the future.
To understand the process of planning.
Time management and problem solving.
To apply the learned manufacturing skills to fabricate useful projects.
EXPLODED VIEW OF PROTOTYPE OF STIRLING ENGINE
crankshaft
Wire nutConnecting rod
Balloon Top
PVC Elbow
Flywheel CD
Crankshaft Support
Wooden Board
Ring Stand
Pressure Vessel Bottom
Displacer
Pressure Vessel Top
/
/
/---
The idealistic stirling engine consist of four basic thermodynamic processes acting on fluid:
1. Isothermal expansion.2. Constant volume heat removal.3. Isothermal compression.4. Constant volume heat addition.
To fabricate the model we followed the following methodology :-
Intensive study along with the analysis of problems. Procurement of materials. Making of ring stand. Making of pressure vessel (top and bottom). Making of displacer (top and bottom).
Making of various other parts and some other small works. Assembly and testing.
1.ISOTHERMAL EXPANSION.
2.CONSTANT VOLUME HEAT REMOVAL.
3.ISOTHERMAL COMPRESSION.
4.CONSTANT VOLUME HEAT ADDITION.
HEAT SOURCEAMBIENTTEMPERATURE
DISPLACER
CONSTANT HEATSOURCE(CANDLE FLAME)
ATMOSPHERRE
Stirling engine is used in the following ways :1. In submarines2. In cry coolers3. In room or space for cooling4. In aero planes where the air gets cooled at higher
altitudes.5. In yatches where silence is valued6. As heat pump as it works irreversible cycle.
MAIN COMPONENTS OF STIRLING ENGINE PROTOTYPE:
RING STANDRING STAND PRESSURE VESSEL TOPPRESSURE VESSEL TOP PRESSURE VESSEL BOTTOMPRESSURE VESSEL BOTTOM DISPLACER TOPDISPLACER TOP DISPLACER BOTTOMDISPLACER BOTTOM CRANKSHAFTCRANKSHAFT CRANKSHAFT SUPPORTCRANKSHAFT SUPPORT
Components Height Diameter Components Height Diameter 1. Ring Stand 5” 2.5”1. Ring Stand 5” 2.5”2. Pressure Vessel To 1” 2.5” 2. Pressure Vessel To 1” 2.5” 3. Pressure Vessel Bottom 3” 2.5”3. Pressure Vessel Bottom 3” 2.5”4. Displacer Top -- 2.4”4. Displacer Top -- 2.4”5. Displacer Bottom 1.5 2.45”5. Displacer Bottom 1.5 2.45”6. Crankshaft Support 6.5” --6. Crankshaft Support 6.5” --7. Connecting Rod 7”(Length)7. Connecting Rod 7”(Length)8. Crankshaft 10”(Length8. Crankshaft 10”(Length))
RING STAND PRESSURE VESSEL BOTTOM
PRESSURE VESSEL TOP
DISPLACER BOTTOM
DISPLACER TOPCRANKSHAFT SUPPORT
CRANKSHAFT
MATERIALS USED : TIN AND ALUMINIUM CANSTIN AND ALUMINIUM CANS STRAIGHT PINSTRAIGHT PIN ¾” PVC ELBOW¾” PVC ELBOW SMALL BALLOONSSMALL BALLOONS FLAT WASHER AND NUTFLAT WASHER AND NUT METAL COAT HANGERMETAL COAT HANGER OLD CDOLD CD WOODEN BASE AND NAILSWOODEN BASE AND NAILS WIRE NUT WIRE NUT GLUING AGENTS LIKE ARALDITE AND M-SEAL.GLUING AGENTS LIKE ARALDITE AND M-SEAL.
1. Tin Snips 1. Tin Snips 2. Stainless Steel Scissors2. Stainless Steel Scissors3. Hammer3. Hammer4. Pliers4. Pliers5. Hexaframe5. Hexaframe6. Wooden Mallet6. Wooden Mallet7. Drilling Machine7. Drilling Machine8. Grinding Machine8. Grinding Machine
MATERIAL NUMBERS COST
ALUMINIUM AND TIN CANS
6 180
WOODEN BOARD 1 30
GLUING AGENTS 5 17
OTHERS MATERIALS AND MISCELLENEOUS COSTS
170
TOTAL = Rs.550
Opening of the can lid for making pressure vessel top ,pressure vessel bottom, displacer top and displacer bottom.
Non linear motion of straight pin through the hole of pressure vessel top.
Sliding of crankshaft through the holes in crankshaft supports.
Dissipation of heat from the space between the legs of ring stand.
Maintaining exact length of connecting rod through PVC elbow.
Can lid was removed by the grinding process.
The non–linear motion of straight pin was restricted using cap at the top of pressure vessel top.
Sliding of the crankshaft through the holes of the crankshaft supports was stopped using washer and m-seal.
Dissipation of heat is prevented using GI sheet wrapped around ring stand.
Length of connecting rod is still an area of concern .