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Theory of machine| part -1

Kinematics links - Every part of machine which have relative motion to another part.   → The link should be resistance body.   What is resistant body? →Under the action of force it can transfer motion and power. Kinematics links →1. Rigid links     2. Flexible links     3. Fluid links Rigid links - There is no deformation.   Ex - piston,connecting rod Flexible links - Deformation is allowed under permissible limits. Ex - Belt drive Fluid links - A fluid link is one that is deformed by having fluid in a closed vessel and the motion is transmitted through the fluid by pressure. Ex - Hydraulic press   Types of links - 1. Singular 2. Binary 3. Ternary 4. Quaternary links
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Full details of dual cycle

                         I.C ENGINE
Dual cycle : It is also called as limited pressure cycle or it also called as mixed cycle.
→In this process heat addition process takes place both at constant volume & constant pressure.
→ This cycle is used for heavy duty diesel engine.

The process which takes place in dual cycle are -
A. Process (1-2) : Reversible adiabetic(isentropic)compression.
B. Process(2-3) : Constant volume heat addition.
C. Process(3-4) : Constant pressure heat addition.
D. Process(4-5) : Reversible adiabetic(isentropic) expansion.
E. Process(5-1) : Constant volume heat rejection.
At bellow pV diagram and T-S diagram



1.At point 1, Air enters the cylinder or air is completely filled in the cylinder.
2. Process(1-2) : Compression of air takes place & it is reversible adiabetic compression.
3. During compression process,there is decrease in volume with corresponding in pressure keeping the entropy constant.
4. At the point 2,heat addition( fuel addition) starts & it is added at constant volume upto 3.
During point(2-3) volume is constant pressure & temperature increase.
5. At point 3, heat addition at constant pressure upto 4.
During process(3-4)pressure is constant volume & temperature increase.
6. Once the heat addition process has been completed,there is the isentropic expansion of air.expansion takes place point(4-5).
During expansion entropy remain constant,pressure & temperature drop of air.
7. After expansion,heat rejected starts from point 5 & heat is rejected at constant volume from (5-1).
During this process both pressure & temperature decrease.

* Efficiency of dual cycle can be calculated by following this concept :-
→Heat is added constant volume(QA1)=Cv (T3  -T2)
→Heat is added constant pressure(QA2)=Cp (T4 - T3)
→Total heat added (QA1+ QA2)=Cv (T3  -T2)+Cp (T4 - T3)
→Workdone(W.D)=heat addition - heat rejection = Cv (T3  -T2)+Cp (T4 - T3)-Cv(T5 - T1)
→Efficiency(η) =W.D/QA1+ QA2

 ** NOTE-- QA = heat addition

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