Question

In an ideal Diesel cycle, indicate whether the following statements are true or false: a)-All the processes are internally reversible. b)- Cycle efficiency increases with the maximum temperature. c)- Cycle efficiency depends on the compression ratio only.

Answer 1

Answer:

a)True

b)False

c)False

Explanation:

We know that ideal diesel cycle is the ideal cycle for all practically used diesel cycle.  Ideal cycle do not have any internal or internal ir-reversibility ,all the processes are reversible process.

In diesel engine there are four process

Process 1-2:Reversible adiabatic compression process

Process 2-3:Constant pressure heat addition

Process 3-4-:Reversible adiabatic expansion process

Process 4-1:Constant volume heat rejection

Efficiency of diesel engine  given as follows

$\eta =1-\dfrac{\rho ^{\gamma}-1}{r^{\gamma -1}\gamma \left (\rho -1\right )}$

So it is clear that Efficiency is not only a function of compression ratio(r) only.

When maximum temperature will increases then cut of ratio(ρ)also will increases and this leads to decrease in the efficiency of cycle.

So

a)True

b)False

c)False