TOPIC​ ​:​ ​5​ ​:​ ​Flywheel​ ​and​ ​Governor

Q.1.​ ​Draw​ ​turning​ ​moment​ ​diagram​ ​for​ ​four-stroke​ ​I.C.​ ​Engine.

Total​ ​crank​ ​angle​ ​turned​ ​by​ ​crank​ ​is​ ​ 7200 (4π) ​ ​in​ ​one​ ​cycle.​ ​There​ ​are​ ​Four​ ​strokes. 1.​ ​Suction​ ​–​ ​During​ ​the​ ​stroke​ ​work​ ​is​ ​done​ ​on​ ​gases,​ ​hence​ ​there​ ​is​ ​negative​ ​loop. 2.​ ​Compression​ ​–​ ​During​ ​this​ ​stroke​ ​again​ ​work​ ​done​ ​on​ ​gases​ ​hence​ ​move​ ​negative​ ​loop. 3.​ ​Expansion​ ​–​ ​During​ ​this​ ​stroke​ ​the​ ​work​ ​is​ ​done​ ​by​ ​gases​ ​hence​ ​bigger​ ​positive​ ​loop.​ ​Actually​ ​in​ ​this stroke​ ​the​ ​engine​ ​gets​ ​the​ ​power​ ​which​ ​keeps​ ​it​ ​moving 4.​ ​Exhaust​ ​–​ ​During​ ​this​ ​stroke​ ​the​ ​gases​ ​are​ ​driven​ ​out​ ​hence​ ​small​ ​negative​ ​&​ ​positive​ ​loops

Q.2.​ ​Explain​ ​turning​ ​moment​ ​diagram​ ​for​ ​multi​ ​cylinder​ ​in​ ​line​ ​4​ ​stroke Ans.

Figure​ ​shows​ ​the​ ​turning​ ​moment​ ​diagram​ ​for​ ​a​ ​three​ ​cylinder​ ​engine..In​ ​multi​ ​cylinder​ ​engine​ ​the​ ​cranks​ ​of various​ ​pistons​ ​are​ ​arranged​ ​such​ ​that​ ​there​ ​occurs​ ​one​ ​power​ ​stroke​ ​in​ ​every​ ​180​ ​degrees.​ ​Due​ ​to​ ​this​ ​the turning​ ​moment​ ​diagram​ ​is​ ​smooth​ ​and​ ​hence​ ​multi​ ​cylinder​ ​engine​ ​requires​ ​small​ ​flywheel.

Developed​ ​By​ ​:​ ​Shaikh​ ​sir’s​ ​Reliance​ ​Academy,​ ​Near​ ​Malabar​ ​Hotel,​ ​Station​ ​road,​ ​Kolhapur​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​Contact​ ​:[email protected] 

 

Q.3.​ ​What​ ​is​ ​function​ ​of​ ​flywheel OR Why​ ​flywheel​ ​is​ ​necessary​ ​for​ ​an​ ​engine​ ​?

Ans. “​A​ ​flywheel​ ​is​ ​an​ ​inertial​ ​energy-storage​ ​device​.​ ​It​ ​absorbs​ ​mechanical​ ​energy​ ​and​ ​serves​ ​as​ ​a​ ​reservoir, storing​ ​energy​ ​during​ ​the​ ​period​ ​when​ ​the​ ​supply​ ​of​ ​energy​ ​is​ ​more​ ​than​ ​the​ ​requirement​ ​and​ ​releases​ ​it during​ ​the​ ​period​ ​when​ ​the​ ​requirement​ ​of​ ​energy​ ​is​ ​more​ ​than​ ​the​ ​supply.​” The​ ​main​ ​function​ ​of​ ​flywheel​ ​is​ ​to​ ​control​ ​energy​ ​fluctuations​ ​in​ ​engine​ ​during​ ​one​ ​cycle. Flywheel​ ​as​ ​an​ ​energy​ ​storage​ ​device​ ​which​ ​stores​ ​energy​ ​in​ ​the​ ​form​ ​of​ ​K.E.​ ​When​ ​the​ ​engine​ ​produces addition​ ​energy​ ​is​ ​to​ ​power​ ​stroke.​ ​The​ ​flywheel​ ​absorb​ ​the​ ​energy​ ​&​ ​when​ ​engine​ ​required​ ​the​ ​energy.​ ​If supplied​ ​by​ ​flywheel. If​ ​flywheel​ ​is​ ​not​ ​provided​ ​in​ ​engine​ ​it​ ​will​ ​cause​ ​high​ ​speed​ ​fluctuation​ ​which​ ​will​ ​be​ ​of​ ​no​ ​practical​ ​use.

Q.4.​ ​List​ ​Functions​ ​of​ ​fly​ ​wheel.

Ans. 1.​ ​To​ ​control​ ​energy​ ​fluctuation​ ​in​ ​an​ ​engine. 2.​ ​It​ ​acts​ ​as​ ​a​ ​reservoir 3.​ ​It​ ​absorbs​ ​energy​ ​when​ ​it​ ​is​ ​extra​ ​&​ ​supplies​ ​energy​ ​when​ ​it​ ​is​ ​required.

Q.5.​ ​State​ ​function​ ​of​ ​Governor.

Ans.​ ​“​To​ ​maintain​ ​the​ ​speed​ ​of​ ​prime​ ​mover​ ​within​ ​specified​ ​limits​ ​irrespective​ ​of​ ​load​ ​changes.” When​ ​there​ ​is​ ​change​ ​in​ ​load,​ ​variation​ ​in​ ​speed​ ​also​ ​takes​ ​place​ ​then​ ​governor​ ​operates a​ ​regulatory​ ​control​ ​and​ ​adjusts​ ​the​ ​fuel​ ​supply​ ​to​ ​maintain​ ​the​ ​mean​ ​speed​ ​nearly​ ​constant.​ ​Therefore,​ ​the governor​ ​automatically​ ​regulates​ ​energy​ ​supply​ ​to​ ​the​ ​prime​ ​mover​ ​as​ ​demanded​ ​by​ ​variation​ ​of​ ​load​ ​so​ ​that the​ ​prime​ ​mover​ ​speed​ ​is​ ​maintained​ ​nearly​ ​constant.

Q.6.​ ​Classify​ ​Governors.

The​ ​broad​ ​classification​ ​of​ ​governor​ ​can​ ​be​ ​made​ ​depending​ ​on​ ​their​ ​operation. (a)​ ​Centrifugal​ ​governors ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​a)​ ​Gravity​ ​controlled​ ​governers 1.Watts​ ​Governer 2.Porter​ ​Governer 3.Proell​ ​Governer. b)​ ​Spring​ ​Controlled​ ​Governers 1.​ ​Hartnell​ ​governor 2.​ ​Wilson-Hartnell​ ​governor 3.​ ​Hartung​ ​governor (b)​ ​Inertia​ ​and​ ​flywheel​ ​governors. (c)​ ​Pickering​ ​governors.

Q.7.​ ​Explain​ ​with​ ​sketch​ ​Watts​ ​Governor. Developed​ ​By​ ​:​ ​Shaikh​ ​sir’s​ ​Reliance​ ​Academy,​ ​Near​ ​Malabar​ ​Hotel,​ ​Station​ ​road,​ ​Kolhapur​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​Contact​ ​:[email protected] 

 

Principle​​ ​–​ ​The​ ​governor​ ​works​ ​on​ ​the​ ​principle​ ​of​ ​centrifugal​ ​force​ ​acting​ ​on​ ​body. Construction​​ ​–​ ​As​ ​shown​ ​in​ ​fig.​ ​Governor​ ​consists​ ​of​ ​two​ ​sets​ ​are​ ​arm​ ​having​ ​fly​ ​balls​ ​attack​ ​to​ ​them.​ ​The lower,​ ​arm​ ​is​ ​connected​ ​to​ ​sleeve​ ​&​ ​both​ ​appear​ ​arm​ ​are​ ​connected​ ​to​ ​common​ ​spindle​ ​the​ ​spindle​ ​is​ ​driven by​ ​shaft​ ​of​ ​prime​ ​mover​ ​the​ ​bevel​ ​gearing. Working​​ ​-​ ​When​ ​the​ ​load​ ​on​ ​engine​ ​increases​ ​the​ ​speed​ ​of​ ​engine​ ​decreases,​ ​due​ ​to​ ​decreases​ ​in​ ​speed​ ​the centrifugal​ ​force​ ​acting​ ​on​ ​balls​ ​decreases​ ​as​ ​a​ ​result​ ​fly​ ​balls​ ​move​ ​in​ ​inward​ ​direction​ ​.The​ ​inward movement​ ​of​ ​ball​ ​the​ ​sleeve​ ​move​ ​down,​ ​the​ ​movement​ ​of​ ​sleeve​ ​increases​ ​the​ ​quantity​ ​of​ ​fuel​ ​going​ ​to engine​ ​thus​ ​the​ ​speed​ ​is​ ​again​ ​increases. When​ ​the​ ​load​ ​on​ ​engine​ ​decreases​ ​the​ ​speed​ ​of​ ​engine​ ​increases​ ​due​ ​to​ ​increases​ ​in​ ​speed​ ​of centrifugal​ ​force​ ​acting​ ​on​ ​a​ ​balls​ ​increases​ ​as​ ​a​ ​result​ ​fly​ ​balls​ ​movement​ ​in​ ​outward​ ​direction.​ ​The​ ​outward movement​ ​of​ ​ball​ ​the​ ​sleeve​ ​move​ ​up​ ​the​ ​movement​ ​of​ ​sleeve​ ​decreases​ ​the​ ​quantity​ ​of​ ​fuel​ ​going​ ​to​ ​engine thus​ ​the​ ​speed​ ​is​ ​again​ ​decreases.

Developed​ ​By​ ​:​ ​Shaikh​ ​sir’s​ ​Reliance​ ​Academy,​ ​Near​ ​Malabar​ ​Hotel,​ ​Station​ ​road,​ ​Kolhapur​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​Contact​ ​:[email protected] 

 

Q.8.​ ​Explain​ ​with​ ​sketch​ ​Porter​ ​Governor.

Construction​ ​-Porter​ ​governor​ ​is​ ​modification​ ​of​ ​Walt's​ ​governor​ ​.​ ​It​ ​has​ ​an​ ​additional​ ​dead​ ​weight​ ​on sleeve.​ ​Due​ ​to​ ​this​ ​weight​ ​the​ ​sensitivity​ ​&​ ​instability​ ​problems​ ​of​ ​Watt's​ ​governor​ ​are​ ​solved. Working​ ​–​ ​same​ ​at​ ​Walt's​ ​governor.

Q.9.​ ​Explain​ ​with​ ​sketch​ ​Proell​ ​Governor. Proell​ ​governor​ ​is​ ​modification​ ​of​ ​Watt's​ ​governor​ ​. ​ ​It​ ​has​ ​two​ ​changes​ ​in​ ​Walt's​ ​governor. i]​ ​Additional​ ​dead​ ​weight​ ​on​ ​sleeve. ii]​ ​The​ ​fly​ ​balls​ ​are​ ​placed​ ​on​ ​bell​ ​crank​ ​lever. ​ ​ ​ ​ ​ ​ ​ ​Working​ ​–​ ​same​ ​at​ ​Walt's​ ​governor.

Developed​ ​By​ ​:​ ​Shaikh​ ​sir’s​ ​Reliance​ ​Academy,​ ​Near​ ​Malabar​ ​Hotel,​ ​Station​ ​road,​ ​Kolhapur​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​Contact​ ​:[email protected] 

 

Q.10.Explain​ ​Hartnell​ ​Governor

Construction​ ​– It​ ​is​ ​a​ ​Spring​ ​loaded​ ​Governor​ ​.​ ​It​ ​ ​has​ ​two​ ​bell​ ​crank​ ​levers​ ​carrying​ ​fly​ ​ball​ ​at​ ​one​ ​end​ ​and​ ​roller​ ​attached to​ ​other​ ​end,​ ​the​ ​function​ ​of​ ​spring​ ​is​ ​provide​ ​the​ ​counter​ ​force​ ​which​ ​acts​ ​against​ ​centrifugal​ ​force.​ ​The spring​ ​and​ ​shaft​ ​is​ ​enclosed​ ​inside​ ​a​ ​casing​ ​.The​ ​sleeve​ ​is​ ​pressed​ ​against​ ​the​ ​spring​ ​when​ ​the​ ​centrifugal force​ ​on​ ​the​ ​balls​ ​increases.​ ​Due​ ​to​ ​spring​ ​return​ ​nature​ ​this​ ​governor​ ​can​ ​be​ ​mounded​ ​in​ ​horizontal,inverted, (inclined)​ ​position.

Developed​ ​By​ ​:​ ​Shaikh​ ​sir’s​ ​Reliance​ ​Academy,​ ​Near​ ​Malabar​ ​Hotel,​ ​Station​ ​road,​ ​Kolhapur​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​Contact​ ​:[email protected] 

 

Q11:Explain​ ​With​ ​sketch​ ​Hartung​ ​Governor

Construction​ ​– It​ ​is​ ​a​ ​Spring​ ​Controlled​ ​Governor​ ​.​ ​It​ ​consists​ ​of​ ​two​ ​bell​ ​crank​ ​levers,​ ​each​ ​carrying​ ​fly​ ​ball​ ​at​ ​one​ ​end​ ​the others​ ​end​ ​of​ ​bell​ ​crank​ ​lever​ ​is​ ​connected​ ​to​ ​sleeve​ ​which​ ​is​ ​free​ ​to​ ​move​ ​up​ ​and​ ​down.​ ​The​ ​fly​ ​balls​ ​are connected​ ​to​ ​body​ ​through​ ​springs.The​ ​function​ ​of​ ​springs​ ​is​ ​to​ ​provide​ ​counteracting​ ​force​ ​against centrifugal​ ​force.

Developed​ ​By​ ​:​ ​Shaikh​ ​sir’s​ ​Reliance​ ​Academy,​ ​Near​ ​Malabar​ ​Hotel,​ ​Station​ ​road,​ ​Kolhapur​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​Contact​ ​:[email protected] 

 

Q.12​ ​Explain​ ​with​ ​Sketch​ ​Wilson​ ​Hartnell​ ​Governor.

WILSON-HARTNELL​ ​GOVERNOR A​ ​Wilson-hartnell​ ​governor​ ​is​ ​also​ ​a​ ​spring​ ​loaded​ ​type​ ​governor.​ ​In​ ​this​ ​governor,​ ​the​ ​balls,​ ​which​ ​are mounted​ ​on​ ​vertical​ ​arms​ ​of​ ​bell​ ​crank​ ​lever​ ​are​ ​connected​ ​by​ ​two​ ​radial​ ​springs​ ​as​ ​shown​ ​in​ ​fig​ ​8.17.​ ​These springs​ ​control​ ​the​ ​centrifugal​ ​force​ ​of​ ​the​ ​balls.​ ​In​ ​this​ ​governor,​ ​the​ ​initial​ ​tensions​ ​in​ ​the​ ​radial​ ​springs​ ​are not​ ​adjustable,​ ​so​ ​an​ ​adjustable​ ​auxiliary​ ​spring​ ​is​ ​used​ ​which​ ​is​ ​connected​ ​to​ ​sleeve​ ​through​ ​a​ ​lever.​ ​When the​ ​speed​ ​of​ ​engine​ ​increases,​ ​balls​ ​try​ ​to​ ​fly​ ​out​ ​and​ ​sleeve​ ​moves​ ​upward​ ​causing​ ​tensions​ ​in​ ​radial​ ​springs. The​ ​auxiliary​ ​springs​ ​tries​ ​to​ ​bring​ ​the​ ​sleeve​ ​down.

Developed​ ​By​ ​:​ ​Shaikh​ ​sir’s​ ​Reliance​ ​Academy,​ ​Near​ ​Malabar​ ​Hotel,​ ​Station​ ​road,​ ​Kolhapur​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​Contact​ ​:[email protected] 

 

Q.13.​ ​Define​ ​the​ ​following​ ​terms​ ​related​ ​to​ ​the​ ​flywheel​ ​ ​(IMP) 1.​ ​Coefficient​ ​of​ ​fluctuation​ ​of​ ​speed 2.Coefficient​ ​of​ ​fluctuation​ ​ ​of​ ​energy.

Ans: Coefficient​ ​of​ ​fluctuation​ ​of​ ​energy “The​ ​ratio​ ​of​ ​the​ ​maximum​ ​fluctuation​ ​of​ ​energy​ ​to​ ​the​ ​work​ ​done​ ​per​ ​cycle​ ​is​ ​defined​ ​as​ ​the coefficient​ ​of​ ​fluctuation​ ​of​ ​energy.” Let,​ ​ ​ ​ ​ ​W​ ​=​ ​work​ ​done​ ​per​ ​cycle​ ​(Nm)​ ​and​ ​K​e​=​ ​Coefficient​ ​of​ ​fluctuation​ ​of​ ​energy emax Then, ke = W ​ ​ ​ ​ ​Where​ ​work​ ​done​ ​per​ ​cycle​ ​is​ ​the​ ​area​ ​under​ ​T-​ ​ θ ​ ​curver​ ​in​ ​the​ ​turning​ ​moment​ ​diagram. Coefficient​ ​of​ ​fluctuation​ ​of​ ​speed “The​ ​different​ ​between​ ​the​ ​greatest​ ​speed​ ​and​ ​the​ ​least​ ​speed​ ​is​ ​known​ ​as​ ​maximum fluctuation​ ​of​ ​speed​ ​and​ ​the​ ​ratio​ ​of​ ​the​ ​maximum​ ​fluctuation​ ​of​ ​speed​ ​to​ ​the​ ​mean​ ​speed​ ​is​ ​the​ ​coefficient​ ​of fluctuation​ ​of​ ​speed.” Let,​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ w1 = maximum speed of f lywheel ​ ​ ​ ​ ​ ​ ​ ​ w2 = minimum speed of f lywheel ​ ​ ​ ​ ​ ​ ​ ​ w = coef f icient of f luctuation of speed ​ ​ ​ ​ ​ ​ ​ ​ k s = C o − ef f icient of f luctuation speed, expressed in percentages. Then,

w1 =

w1 + w2 2

q= and

k=

w1 + w2 w w1 + w2 w

× 100

Q.14.Define​ ​the​ ​following​ ​terms​ ​related​ ​to​ ​governor.(Imp)

Sensitiveness.​​ ​The​ ​sensitiveness​ ​is​ ​defined​ ​as​ ​the​ ​ratio​ ​of​ ​the​ ​difference​ ​between​ ​the​ ​maximum​ ​and minimum​ ​equilibrium​ ​speeds​ ​to​ ​the​ ​mean​ ​equilibrium​ ​speed.​ ​It​ ​is​ ​an​ ​indicator​ ​of​ ​variation​ ​in​ ​speeds​ ​at different​ ​loads​ ​conditions.​ ​It​ ​is​ ​considered​ ​that​ ​for​ ​a​ ​small​ ​change​ ​in​ ​load​ ​there​ ​should​ ​be​ ​minimum​ ​change in​ ​the​ ​configuration​ ​of​ ​governor. .​ ​According​ ​to​ ​this​ ​definition​ ​of​ ​sensitiveness,​ ​it​ ​is​ ​expressed​ ​as S ensitiveness =

N 1+ N 2 2(N 1 − N 2 )

Where​ ​,​ ​ N 1 = maximum speed and ​ ​ N 2 = minimum speed HUNTING A​ ​governor​ ​is​ ​said​ ​to​ ​be​ ​hunt​​ ​if​ ​the​ ​speed​ ​of​ ​the​ ​engine​ ​fluctuates​ ​continuously​ ​above​ ​and​ ​below​ ​the​ ​mean speed​ ​.​ ​This​ ​is​ ​caused​ ​by​ ​a​ ​too​ ​sensitive​ ​governor​ ​which​ ​changes​ ​the​ ​fuel​ ​supply​ ​by​ ​a​ ​large​ ​amount​ ​when​ ​a small​ ​change​ ​in​ ​the​ ​speed​ ​of​ ​rotation​ ​takes​ ​place. Stability​ ​of​ ​governor. A​ ​governor​ ​is​ ​said​ ​to​ ​be​​ ​stable​​ ​when​ ​for​ ​every​ ​speed​ ​within​ ​the​ ​working​ ​range​ ​there​ ​is​ ​a​ ​definite configuration​ ​i​ ​.​ ​e​ ​.​ ​there​ ​is​ ​only​ ​one​ ​radius​ ​of​ ​rotation​ ​of​ ​the​ ​governor​ ​balls​ ​at​ ​which​ ​the​ ​governor​ ​is​ ​in equilibrium.​ ​For​ ​a​ ​stable​ ​governor,​ ​if​ ​the​ ​equilibrium​ ​speed​ ​increases,​ ​the​ ​radius​ ​of​ ​governor​ ​balls​ ​must​ ​also increase. ISOCHRONISM A​ ​governor​ ​with​ ​a​ ​range​ ​of​ ​speed​ ​zero​ ​is​ ​known​ ​as​ ​an​ ​isochronous​ ​governor.This​ ​mean​ ​that​ ​the​ ​for​ ​all positions​ ​of​ ​the​ ​sleeve​ ​or​ ​the​ ​balls,​ ​the​ ​governor​ ​has​ ​the​ ​same​ ​equilibrium​ ​speed.​ ​Any​ ​change​ ​of​ ​speed results​ ​in​ ​moving​ ​the​ ​balls​ ​and​ ​the​ ​sleeve​ ​to​ ​their​ ​extreme​ ​positions.​ ​However,​ ​an​ ​isochronous​ ​governor​ ​is not​ ​practical​ ​due​ ​to​ ​friction​ ​at​ ​the​ ​sleeve.

Developed​ ​By​ ​:​ ​Shaikh​ ​sir’s​ ​Reliance​ ​Academy,​ ​Near​ ​Malabar​ ​Hotel,​ ​Station​ ​road,​ ​Kolhapur​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​Contact​ ​:[email protected] 

 

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Subtopic​ ​5.3​ ​:​ ​Comparison​ ​between​ ​ ​flywheel​ ​and​ ​governor -----------------------------------------------------------------------------------------Q.15.​ ​Compare​ ​flywheel​ ​and​ ​Governor​ ​.(Imp) Sr​ ​no

Factors

Governor

Flywheel

1

Function

To​ ​control​ ​variations

To​ ​control​ ​mean​ ​speed​ ​of​ ​an engine​ ​during​ ​variations​ ​in​ ​load.

2

Control​ ​of​ ​speed

It​ ​controls​ ​the​ ​speed​ ​over​ ​no. of​ ​cycles​ ​of​ ​a​ ​prime-mover.

It​ ​controls​ ​the​ ​speed​ ​during​ ​one cycle​ ​and​ ​the​ ​same​ ​is​ ​repeated for​ ​each​ ​cycle.

3

Method​ ​of​ ​working

It​ ​regulates​ ​the​ ​quantity​ ​of working​ ​fluid​ ​of​ ​the prime-mover

It​ ​stores​ ​up​ ​the​ ​energy​ ​and​ ​gives it​ ​whenever​ ​it​ ​is​ ​required​ ​during each​ ​cycle.

4

Working​ ​instance

It​ ​works​ ​intermittently​ ​i.e. when​ ​there​ ​is​ ​change​ ​in​ ​the load.

It​ ​works​ ​from​ ​cycle​ ​to​ ​cycle

5

Reduction​ ​in

It​ ​economizes​ ​the​ ​working fluid​ ​consumption

It​ ​reduces​ ​capital​ ​investment​ ​on prime-mover​ ​and​ ​their​ ​running expenses.

Developed​ ​By​ ​:​ ​Shaikh​ ​sir’s​ ​Reliance​ ​Academy,​ ​Near​ ​Malabar​ ​Hotel,​ ​Station​ ​road,​ ​Kolhapur​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​Contact​ ​:[email protected]