- #1

jdawg

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## Homework Statement

A four cylinder, four stroke internal combustion engine has a bore of 3.7 in and a stroke of 3.4 in. The clearance volume is 16% of the cylinder volume at bottom dead center and the crankshaft rotates at 2400 RPM. The processes within each cylinder are modeled as an air standard Otto cycle with a pressure of 14.5 lbf/in

^{2}and a temperature of 60 °F at the beginning of compression. The maximum temperature in the cycle is 5200 °R. Based on this model, calculate the net work per cycle in Btu and the power developed by the engine in horse power.

## Homework Equations

## The Attempt at a Solution

So p1=14.5 lbf/in

^{2}and T1=520°R. The max temperature is at T3 so T3=5200°R. V3=V2. V4=V1.

And they tell you in the problem that the clearance volume ( V2) is 16% of the volume at bottom dead center (V1). I would think that meant V2=(0.16)*(V1), but the solution I'm looking at says V2=(0.16)*(V1+V2).

What exactly is the stroke? All my book says about it is that its the distance the piston moves in one direction, which kind of makes me think its the total volume? The solution I have kind of treats it as a height because they multiply the stroke by the area they calculated with the bore:

ΔV

_{1-2}=(π(3.7/2)

^{2})(3.4)=0.02116 ft

^{3}

I feel like the terminology is the main thing that's tripping me up. If someone could clarify I would really appreciate it! :)