I don't want to know what the hell any boater is up to who would need to know more than that load of
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Propane pressure gauge
- Thread starter GreenSailor2
- Start date
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Excellent question! I'd like to hear from someone who's tried. I don't know if it would be accurate enough to determine the level.
Now that I think of it, I believe you put "warm" or "hot water" on the tank and then feel where the temperature is cooler, that is the tank level. The IR gun should easily be able to tell this. I have read that the temperature is even enough to tell by you hand.
Isn’t the temperature difference the principle behind the level indicator stickers @JamesG161 mentioned back in post #7?
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,281
Ok... You picked my interest.
Grill Propane tank. Stored outside over night. Has not been used in several days. Tank has been closed so should be stable. Ambient air temp 54.
Not sure what this demonstrates. I believe the tank is about 50% full.
Grill Propane tank. Stored outside over night. Has not been used in several days. Tank has been closed so should be stable. Ambient air temp 54.
Not sure what this demonstrates. I believe the tank is about 50% full.
Gas needs to be flowing to show the temperature difference. The slight differences you saw are probably just from the ambient air and suns heating the tank unevenly.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,281
No sun David. The tank had been covered all night and the sunrise 06:37. Sun still below the level of the treees and hidden behind the corner of the house so not a factor at 07:49 when I took the images
@jssailem , turn the gas on full bore for about 10-15 sec. and you should see a drop in the temperature where the liquid is sitting.
@JamesG161 , rise and shine. Time to resume the fray
.I say the small temperature rise from the bottom to the top of the tank was due to the rise in ambient air temperature from the night time low. The liquid propane has more thermal conductivity plus greater specific heat than the gas propane so will hold its lower temperature longer. The upper section of the tank which only contacts the gaseous propane warms more quickly due to the opposite thermal conditions.
But that's too simple a method. We seek process we can argue and debate until the cows return to roost and hopefully come to no concrete resolution
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When things are stable as in no gas being demanded by a load, there is little driver for the heat transfer thus little measurable cooling effect. Realistically, without any latent heat transfer (boiling of the liquid into gas) you won't see much temperature difference. You need to apply something to cause the "heat to flow"
Try the temperature guage once you have run some hot water along the side of the tank. Where there is liquid the temperature should lower more quickly than where there is gas since the thermal conductivity of the liquid is higher than that of the gas
Heat Transfer Equation: Q=UA delta T Where Q is the transfer of energy (in the form of heat transfer), U is the thermal conductivity, A is the surface area, and delta T is the temperature difference.
Simplified theory - When you pour the hot water on the tank you set the Delta T (in the short term). The A is about the same, so the only difference is the thermal conductivity (U) of the gas and the liquid. Therefore, more heat will be transferred from the warm tank surface to the liquid than the warm tank surface to the gas and the area exposed to the liquid will cool down more quickly. Ain't it wonderful how Thermodynamics works and you thought you'd never use that equation again.
I guess you're not feeling better yet?But that's too simple a method. We seek process we can argue and debate until the cows return to roost and hopefully come to no concrete resolution
Ok but first watch this video and note the scale to weigh the fill, plus good safety tips included.
Then give me the Latent Heat of Vaporization , Ideal Gas Law and other physical properites.
Jim...
PS: Sends Ralph a Chicken Soup recipe do help him recover from Covid.
You think gas laws are complicated? God forbid we get into the technicalities of chicken soup recipes!
And by the way. I always serve my chicken soup very hot because then it is expanded and thus there is more soup in the bowl compared to when it is only lukewarm. You get more when you eat it hot!
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Chicken soup may produce Methane in Ralph.