Here is the Wolfram Calculator for Speed of Sound I use.... http://www.wolframalpha.com/widgets/view.jsp?id=b63c87b0a41016ad29313f0d7393cee8 .... put in "air 20 C 4000 psi" and see what the output is.... You have to change the input criteria to see different data.... Here is another calculator that does the same thing....http://www.peacesoftware.de/einigewerte/einigewerte_e.html .... but it only has Cp, not k.... I don't know where Scott got the data on gamma he sent me, all I did was use Excel to create a trendline equation from that data, as he gave in post #5.... you would have to ask Scott where he got the values of k.... a different Wolfram calculator, I guess....Bob
I played with the specific heat "widget" for a while this afternoon, made a fewrough checks as to accuracy.....it's the real deal. However, it seems to be an online tool so I'm still without the equations that it uses. The idea I had wasto be able to incorporate this piece of the puzzle directly into Excel, making thermo calculations more accurate. In my opinion, it's a much better approachthan letting an overall efficiency factor serve as a "catch-all". The existence ofthe widget is a clear indication it can be done.Lloyd, Bob, Scott........what do you think? Ron