How to find Indicated mean effective pressure?

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AI Thread Summary
To calculate the Indicated Mean Effective Pressure (IMEP) for a 4-stroke, single-cylinder engine, the user needs to determine the bore and stroke, which are not provided in the problem statement. They have calculated the indicated power using mechanical efficiency but are struggling to find the effective pressure without the dimensions of the engine. The user attempted to apply the compression ratio and the law PV=constant but did not achieve results. The discussion highlights the importance of having complete data for accurate calculations in engine performance analysis. The user also suggests that the forum could benefit from a section addressing unanswered questions.
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Homework Statement




A 4 stroke, single cylinder engine working on constant volume cycle, developes 7.5 KW brake power at 60 rev/sec the mechanical efficiency being 80%. The pressure at the beginning of compression is 0.97 bar, the engine has a volumetric compression ratio of 7 and the maximum pressure reached in the cycle is 34 bar. If both compression and expansion is according to the law PV= costant where n=1.38, calculate Indicate Mean Effective Pressure ?

Homework Equations



indicated power = Pm x Lx A x N

The Attempt at a Solution



well i have tried different methods, but could`nt solve it, if anyone can help me with that ? i`ll b really gratefull. thanks.
 
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the thing is that, there is no stroke or bore given in the question and if i use the volumetric compreesion ratio V1/V2 = 7 and put it in

P1V1^1.38 = P2V2^1.38

then i m getting nothing ? obvioulsy to calculate the Effective Pressure ( Pm ), bore or length of stroke should b known,
through the mechnical efficiney i got the indicated power ! but wat to do next ? kindly guide me.

Pm= Indicated Power/ LAN

how to get AxL ?
 
well i had a very poor experience regarding this forum anyway i do like to leave one suggestion for the admin who r running this forum and that is kindly add one more thing in the topic " Why My Question Is Not Answered ? "

Its not necessary that admin can slove all the prbs, they r also not in full command of the subject.

Byez.
 
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