Reciprocating Compressor Experiment.

1. Oct 23, 2013

SherlockOhms

So, I've recently carried out an experiment to find the volumetric efficiency of a singular reciprocating compressor. During the experiment, there are sub questions asking you to find the value of n and then whether the process is isothermal, poly tropic or adiabatic. Well, n is found to be very close to 1 so the process is isothermal. However, the temperature in the receiver (where the compressed gas is stored) does change by about 3K from t= 0s until t = 180s (when the compressor switches off). Why is that? And, is this therefore not an isothermal process? Or, am I just not properly understanding what's happening? Thanks.

2. Oct 23, 2013

haruspex

From the information posted, it is not possible to tell whether the temperature change observed is small enough to be consistent with the measured difference between n and 1. You could try to compute that.

3. Oct 23, 2013

SherlockOhms

The difference between n and 1? Well, the average value of n was found to be 1.034. So, the difference between n and 1 is 0.034. Is this what you're asking? I may have misunderstood.

4. Oct 23, 2013

haruspex

Yes, that's what I was asking, but the next step is to determine whether the observed rise in temperature is within the range consistent with that n.

5. Oct 23, 2013

SherlockOhms

How do I go about doing that? Only just began this module 3 weeks back so apologies if I'm catching on a bit slowly.

6. Oct 23, 2013

haruspex

Not my area, I'm afraid. I was just pointing out a possible explanation.

7. Oct 24, 2013

SherlockOhms

No problem. Thanks for the help.