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Hi all , I'm putting together a sheet using the CoolProp wrapper It generally works really well except for the following Where I'm getting strange units for the Specific Heat capacity of Air I've tried overriding the units but still don't get what I want (J/kg/K) I've attached an extract from the sheet --> UnitsProblem.sm (8kb) downloaded 77 time(s). Probably a really simple answer but I can't seem to find it !! |
Peter J Francis
Twitter: @PeterJFrancis
Thermal Engineer , Maker , Pilot
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Can't reproduce. J/(kg*K) works. Paste 'J/{'kg*'K} to the square placeholder to the right of the unit when the region has focus. |
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Can't reproduce either "Units don't match", because there is NO heat capacity unit in Smath.
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You just have to change the units. Best Regards Carlos
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Thanks All, You are all correct (I knew the answer was going to be obvious ) , pasting in the units J/kg K works fine
Its just that Gy/K seems an odd default unit
Thanks for your help
Peter |
Peter J Francis
Twitter: @PeterJFrancis
Thermal Engineer , Maker , Pilot
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hey fellows, how do I calculate WET steam properties through this extension,lets suppose at 16Bar Pressure & 0.7 quality 7 which IFP standard is currently being used?
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Originally Posted by: ioncube how do I calculate WET steam properties through this extension,lets suppose at [b]16Bar Pressure Good question. The vapor phase is dry and properties don't change. That portion of water that drags at the bottom of piping must be taken into account for massflow calculation. At the speed steam flows, better be dry. If not => will destroy my control valves. Puzzling question ?
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Originally Posted by: Jean Giraud Originally Posted by: ioncube how do I calculate WET steam properties through this extension,lets suppose at [b]16Bar Pressure Good question. The vapor phase is dry and properties don't change. That portion of water that drags at the bottom of piping must be taken into account for massflow calculation. At the speed steam flows, better be dry. If not => will destroy my control valves. Puzzling question ? The property(s) that does change when you add water to steam is NOT its pressure or temperature but its enthalpy ...the most major parameter which defines the amount of work that can be extracted Yes wet steam at very high velocities can be micro bullets for control valves & turbine blades causing erosion
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Originally Posted by: ioncube The property(s) that does change when you add water to steam is NOT its pressure or temperature but its enthalpy ...the most major parameter which defines the amount of work that can be extracted
Yes wet steam at very high velocities can be micro bullets for control valves Worst than erosion => cavitation. Can't help more. Steam out of the balloon is dry, isn't ? If you have wet steam out of the balloon, you have a serious level control problem.
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