Let me reword this. A 30,000 horizontally oriented gallon tank contains 5,000 gallons of anhydrous ammonia (NH3) at 70 F. 3,000 gallons of NH3 at -20 F is added to it. How long does the mixture take to return to 70 F?
The tank is 3/8" thick carbon steel.
The ambient room temperature is 70 F. Assume perfect mixing.
I tried this problem with a thermal resistance network and just got my temperature differences to cancel each other out.
2007-09-21 08:07:08 · 5 answers · asked by paco r 1 in Science & Mathematics ➔ Engineering
UPDATE: The tank is oriented horizontally, it is made of 3/8" carbon steel and has a 11 foot diameter. Assume that the liquid added is instaneous. I think a iterative solution is needed here. The approach I took was calculate the amount of energy needed to raise the temperature and divide it by the amount of heat enetering the tank. The problem with this is that my delta T cancels out. Any further suggestions?
2007-09-24 02:10:59 · update #1
Depends on the size od the unit used to heat it.
2007-09-21 08:09:35 · answer #1 · answered by bgee2001ca 7 · 0⤊ 0⤋
If you are mixing in a tank and there is no mention of ambient temperature, and the mixing is 'perfect', then tank details become somewhat frivilous. The shortest way to determine it is to assume the tank will reach an equalibrium caused only by the fluid temperatures. ((5000*70)+(3000*-20))/8000=43.4 degrees. the time depends on the rate the fluid is added.
2007-09-21 12:33:06 · answer #2 · answered by mavis b 4 · 0⤊ 0⤋
If you have 5000 gallons at 70 Deg. and 3000 gallons at 40 Deg. your mixture temp is 8000 gallons at 58.75 Deg.
Now all you have to do is calculate how long it will take 8000 gallons of NH3 to increase in temperature from 58.75 Deg to 70 Deg.
The dimensions of the tank, and whether it is vertical or horizontal are important factors in determining the heat transfer rate.
2007-09-21 09:42:24 · answer #3 · answered by gatorbait 7 · 0⤊ 0⤋
I agree with The Questioner.
He is correct that C4 is a lot easier. I suggest that you make a fertilizer bomb though as, although it take a little more work, it is much cheaper and does the job just as effectively. :)
2007-09-21 08:14:42 · answer #4 · answered by Anonymous · 0⤊ 1⤋
why are you asking this?
are you trying to make a bomb or blow something up? if so, then just use c4's man. it's so much easier.
2007-09-21 08:10:17 · answer #5 · answered by the questioner 2 · 0⤊ 1⤋