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ORNL-AMO / AMO-Tools-Desktop

AMO-Tools-Desktop is an energy efficiency calculation application for use with industrial equipment such as pumps, furnaces, fans, and motors, as well as for industrial systems such as steam. Currently in beta.
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Reported issue with conversion between C and F - Psychrometric #5224

Closed gaccawi closed 2 years ago

gaccawi commented 2 years ago

Per reporter:

I am a certified DoE QSPAT auditor and have historically used PSAT on a regular basis.

I am also a lecturer for the UK Royal Institute of Mechanical Engineers.

I have been training some industrial companies with regard to energy management and have been going through psychrometric charts.

As you can appreciate, using manual psychrometric charts is tricky, and therefore, I was hoping to demonstrate the potential of Measur for various elements of energy management.

However, as you can see on this chart, there appears to be a problem in the conversion between temperature of oC and oF with regard to the wet bulb temperature.

The data has been entered on the left as 25oC dry, 21oC wet, however the result page on the right still shows dry as 25oC, but wet, which was a primary entry as 69.8oC, which is not correct, since the result is a oF reading.

gaccawi commented 2 years ago

See attached.

PastedGraphic-1
koay9f commented 2 years ago

I was able to recreate this the first time I played with it, but not since (I did switch between the "Humidity Metric"'s and switched back and forth between unit systems, maybe that "fixed" something). Enthalpy is also displaying in incorrect units above (again, could not replicate more than once) I'll email the user and say we are going to look into it and maybe toggling something or switching between imperial/metric will fix it.

I am a bit concerted that you do not get the same Relative Humidity (and other results) when you plug in data in metric (25, 21, 101350) vs imperial (77, 69.8, 29.929). Could we double check all the unit conversions going to the suite also?

Standalone - imperial: image.png Standalone - metric image.png

Weird - the numbers are the same between imperial & metric for the calc in the fan assessment IF make it in metric and convert to imperial... Fan - imperial (started imperial): image.png Fan - imperial (started from metric): image.png Fan - metric (started as metric): image.png Fan - metric (started as imperial): image.png

koay9f commented 2 years ago

Not 100% sure (though I'm now closer to about 99% :) ), but I think the result where Relative Humidity == 70.3% is correct image.png image.png image.png

koay9f commented 2 years ago

Real issue - something is wrong with pyschrometric calcs in metric (both standalone and in fans, if start the assessment in metric. it is fine if you start in imperial , even if you switch to metric)

rmroot commented 2 years ago

BaseGasDensity values that were not being displayed were not being converted on creation of defaults

koay9f commented 2 years ago

standalone is fixed but the problem still persists if you start a fan assessment in metric

rmroot commented 2 years ago

specificHeatGas hardcoded to .24 for wetBulb calculation