Error in entropy calculation with TH inputs

[somniumAeternam]

I've just came across an error with the calculation of the entropy in CoolProp version 5.0.0:

PropsSI("S","T",328.7253337,"H",274517.1945,"R245fa")

This will return:

Traceback (most recent call last):
File "", line 1, in
File "CoolProp\CoolProp.pyx", line 204, in CoolProp.CoolProp.PropsSI (CoolProp\CoolProp.cpp:15824)
File "CoolProp\CoolProp.pyx", line 236, in CoolProp.CoolProp.PropsSI (CoolProp\CoolProp.cpp:15619)
File "CoolProp\CoolProp.pyx", line 173, in CoolProp.CoolProp.__Props_err2 (CoolProp\CoolProp.cpp:14440)
ValueError: Residual function in secant returned invalid number : PropsSI("S","T",328.7253337,"H",274517.1945,"R245fa")

When I use the Refprop fluid, the value ist calculated correctly:

PropsSI("S","T",328.7253337,"H",274517.1945,"REFPROP::R245fa")
1246.9529300392371

[ibell]

Actually the error should be a different one. TH are not a valid set of
inputs for CoolProp. The reason for that is the presence of multiple
solutions. What sort of calculation gives you TH as inputs?
On Dec 9, 2014 4:47 AM, "somniumAeternam" notifications@github.com wrote:

I've just came across an error with the calculation of the entropy in
CoolProp version 5.0.0:

PropsSI("S","T",328.7253337,"H",274517.1945,"R245fa")

This will return:

Traceback (most recent call last):
File "", line 1, in
File "CoolProp\CoolProp.pyx", line 204, in CoolProp.CoolProp.PropsSI
(CoolProp\CoolProp.cpp:15824)
File "CoolProp\CoolProp.pyx", line 236, in CoolProp.CoolProp.PropsSI
(CoolProp\CoolProp.cpp:15619)
File "CoolProp\CoolProp.pyx", line 173, in CoolProp.CoolProp.__Props_err2
(CoolProp\CoolProp.cpp:14440)
ValueError: Residual function in secant returned invalid number :
PropsSI("S","T",328.7253337,"H",274517.1945,"R245fa")

When I use the Refprop fluid, the value ist calculated correctly:

PropsSI("S","T",328.7253337,"H",274517.1945,"REFPROP::R245fa")
1246.9529300392371

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#319.

[somniumAeternam]

You're right, there are two different solutions. I haven't thought about it. I'm using PH now. Thank you!

[ibell]

Yes it is counter-intuitive, and I don't know how to deal with it, so no TU
or TH.

On Thu, Dec 11, 2014 at 6:38 AM, somniumAeternam notifications@github.com
wrote:

You're right, there are two different solutions. I haven't thought about
it. I'm using PH now. Thank you!

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#319 (comment).