I have made a contour plot via Minitab
and got an image like this one:
With
- $z$ being the enthalpy $[BTU/lb]$
- $x$ being the temperature $[°F]$
- $y$ being the concentration [%]
How can I mathematically access its function $z = f(x,y)$ from just the data behind the picture?
Is there a possibility to get $z = f(x,y)$ from this via programming/software?
EDIT:
Part of my data:
x = Concentration [%] | y = Temperature [°F] | z = Enthalpy [BTU / lb] |
---|---|---|
0 | 32 | 4 |
5 | 32 | -16 |
10 | 32 | -32 |
15 | 32 | -48 |
20 | 32 | -63 |
25 | 32 | -76 |
30 | 32 | -90 |
35 | 32 | -103 |
40 | 32 | -116 |
45 | 32 | -124 |
50 | 32 | -128 |
55 | 32 | -132 |
60 | 32 | -136 |
65 | 32 | -139 |
70 | 32 | -136 |
75 | 32 | -128 |
80 | 32 | -118 |
85 | 32 | -100 |
90 | 32 | -75 |
95 | 32 | -40 |
100 | 32 | 2 |
0 | 50 | 16 |
5 | 50 | 0 |
10 | 50 | -18 |
15 | 50 | -32 |
20 | 50 | -48 |
25 | 50 | -63 |
30 | 50 | -78 |
35 | 50 | -90 |
40 | 50 | -100 |
45 | 50 | -111 |
50 | 50 | -118 |
55 | 50 | -123 |
60 | 50 | -125 |
65 | 50 | -128 |
70 | 50 | -125 |
75 | 50 | -121 |
80 | 50 | -112 |
85 | 50 | -96 |
90 | 50 | -70 |
95 | 50 | -37 |
100 | 50 | 4 |
Picture:
@Claude:
- BTU/lb_5 = – 48,72 + 1,007 Temp – 0,000163 Temp^2
- BTU/lb_10 = – 65,25 + 1,001 Temp – 0,000287 Temp^2
- BTU/lb_15 = – 77,55 + 0,9209 Temp – 0,000163 Temp^2
- BTU/lb_20 = – 90,01 + 0,8385 Temp + 0,000043 Temp^2
- BTU/lb_25 = – 100,7 + 0,7528 Temp + 0,000226 Temp^2
Best Answer
Follows a MATHEMATICA script that I hope, will express with sufficient accuracy, the formulation needed $z = f(x,y)$
Added a python script to define $z = f(x,y)$