# Allow Show in ContourPlot

isoth = ContourPlot[ {v p } , {v, .12, 2}, {p, .12, 2}]
adiab = ContourPlot[ {v^1.4  p} , {v, .12, 2}, {p, .12, 2}]


In an attempt to see heat/work thermodynamics in a Carnot cycle, could not plot hyperbolae type curves together. Please help to Show how the first plot can be made transparent when superimposed on the second and also how to refine level differences say to one fourth the present given default value.

EDIT1:

RegionPlot per Jose Antonio's suggestion for chosen constants

• Add the option , ContourShading -> False for the contour plots. – Jason B. Nov 14 '17 at 18:31
• Not sure if it's what you want, you may use e.g. Contours -> 20, to refine level differences – egwene sedai Nov 14 '17 at 18:43
• Thanks Both fixes have been helpful. Any given answer I accept – Narasimham Nov 14 '17 at 18:52

If you know the equations of your adiabatics and isothermals, you can use:

isoth1 = 1;
isoth2 = 1.5;
RegionPlot[v p > isoth1 && v^(1/4) p > adiab1 && v p < isoth2 && v^(1/4) p < adiab2,
{v, .12, 2.5}, {p, .12, 2.5}, PlotPoints -> 100,
FrameLabel -> (Style[#, 14, Bold] & /@ {"V", "P"}), RotateLabel -> False]


• RegionPlot .Yes looking for that exactly, before going in for ContourPlot ! – Narasimham Nov 14 '17 at 19:46