• Support PF! Buy your school textbooks, materials and every day products Here!

Otto cycle problem

  • Thread starter Dzai
  • Start date
  • #1
1
0

Homework Statement



30idz86.jpg


p1, V1, T1 and ε (compression ratio) are known

I need to find:
p2, p3, p4
T2, T3, T4
V2, V3, V4

but I don't know how to find p3, p4, T3, T4

Homework Equations



ε = V1 / V2
V1 = V4
V2 = V3
T1 * V1^(k - 1) = T2 * V2^(k - 1)
T3 * V3^(k - 1) = T4 * V4^(k - 1)
T1 / T4 = T2 / T3
p * V = R * T

R and k are also known

The Attempt at a Solution



V2 = V1 / ε
V3 = V2
V4 = V1

T2 = T1 * ε ^ (k - 1)

p2 = (R * T2) / V2

And this is where I got stuck

Homework Statement





Homework Equations





The Attempt at a Solution

 

Answers and Replies

  • #2
ehild
Homework Helper
15,498
1,878
The problem is under-defined. You need either P or T for one of the upper points.
For the process 1→2, use the other equation PVk=const to find P2.

ehild
 

Related Threads on Otto cycle problem

  • Last Post
Replies
2
Views
4K
  • Last Post
Replies
1
Views
600
  • Last Post
Replies
7
Views
8K
  • Last Post
Replies
1
Views
522
  • Last Post
Replies
1
Views
10K
  • Last Post
Replies
1
Views
6K
  • Last Post
Replies
0
Views
2K
  • Last Post
Replies
3
Views
4K
  • Last Post
Replies
7
Views
2K
  • Last Post
Replies
1
Views
4K
Top