Recent content by mpreds

A change in enthalpy would indicate that there were parameters in the question that were changing. Do you have initial or final temperatures or any other data? -Mark

Looks correct to me

Are you working from a textbook? Check to see if there is any data tables in the back that may contain concrete. http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html Shows a range of 0.1 - 1.7 for concrete k values

Hi Frock, The equation I suspect you are looking for is as follows: efficiency (turbine) = Actual turbine work / isentropic turbine work

I don't believe your r2/r1 ratio will have much of an effect. Try researching venturi tubes, as yours appears to be the inverse of one. On the most basic of terms. mass flow rate in = mass flow rate out and mass flow rate = density*velocity*cross sectional area and volume flow rate =...

Where did you find your k value? And is it in the correct units? -Mark PS: You did mean to write 10.52 hrs I hope?

Thanks for the correction, my textbooks call it conduction resistance, which is why I called it resistance. I did have my resistance equations inverted for omc1 to integrate it into his/her equation more easily.

Hi omc1, Remember that you can view kA/L as a resistance, and the bar of differing materials would be "resistors" in series. So (k1A/L1) + (k2A/L2) = (kA/L)total You will have to build three separate equations from this information, combine and solve for k2 first then solve for your total q...