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Mechanical Engineering, BEng.. HELP! watch

1. Hi guys ^^

I have a thermofluids report due within the next few weeks which is a research assignment based on isentropic engine cycles.

For part of this we are given the main stages in certain processes and have to figure out which they are, explaining them etc.

I'm struggling with one, if anyone could help? We were given the following stages to use as a base..

Step 1-2, Isentropic compression
Step 2-3, Constant volume, increase in pressure
Step 3-4, Constant pressure, increase in volume
Step 4-5, Isentropic expansion
Step 5-1, Constant volume, decrease in pressure.

If it's any help, other examples were found to be ideal diesel cycles, otto cycles etc.

Thankyou!
2. The Dual-Combustion Cycle

All engines today use solid injection of fuel i.e the fuel is injected by spring-loaded injector, the fuel pump being operated by a cam driven from engine crank shaft. The ideal cycel in this process is know a Dual-Combustion Cycle or mixed cycle.
It's operated by the process you mentioned above.
Heat is supplied in two parts i.e Step 2-3 and Step 3-4. that's why it is known as Dual Combustion Cycle.

Heat supplied can be found by

Q1=Cv(T3-T2)+Cp(T4-T3)

Heat rejected can found using

Q2= Cv(T5-T1)
3. (Original post by doni6333)
The Dual-Combustion Cycle

All engines today use solid injection of fuel i.e the fuel is injected by spring-loaded injector, the fuel pump being operated by a cam driven from engine crank shaft. The ideal cycel in this process is know a Dual-Combustion Cycle or mixed cycle.
It's operated by the process you mentioned above.
Heat is supplied in two parts i.e Step 2-3 and Step 3-4. that's why it is known as Dual Combustion Cycle.

Heat supplied can be found by

Q1=Cv(T3-T2)+Cp(T4-T3)

Heat rejected can found using

Q2= Cv(T5-T1)

Ahh thankyou thankyou!

I did fail to mention, however, that all of these engine cycles are for compression engines, ie not using any kind of fuel, just air. Would I still describe it as you so helpfully did above? Or would it be a different cycle name?
4. couldn't be a Carnot cycle, could it?

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