Bottle Heater Controversy

[dirkdiggler]

Bottle Heater Controversy

What is the effect of bottle temperature on performance? Is a bottle heater even necessary? The general rationale behind a bottle heater is that the nitrous oxide pressure increases with temperature. Consequently the flow rate should increase with temperature. If nitrous oxide were a well behaved liquid and no other effects entered in the picture, power should also increase. However, nitrous oxide is not a well behaved liquid at room temperature. At the critical temperature of 97.58° F, nitrous oxide turns into what physicists refer to as a supercritical fluid - with properties in between those of a liquid and a gas. The latent heat of vaporization rapidly drops above 90° F and reaches zero at the critical temperature. The cooling effect is lost and more airflow is displaced. The result is a slight drop in power, even though the nitrous oxide mass flow rate is increasing. The chart below shows the measured flow rate for a #40 jet and the calculated power gain at various bottle temperatures.








Over a reasonable range of bottle temperatures, power only changes a few percent. If you can keep the bottle temperature above 70° F, you probably don't need to worry about a bottle heater. The optimum temperature appears to be around 80° F - somewhat less than the typical 85° F set point used for most bottle heaters. You don't want the bottle temperature to go much above 80° F as the power starts to drop off.

 

[rxrider]

Great info

 

[yamahajunkie]

so if its 62 or 65 horse, i think your missing the point that it will still be 60+ horse per shot. a 1-5 gain heating the bottle to the optimum temp is kinda silly when your still getting 60 + horsepower. nice chart though

 

[dirkdiggler]

so if its 62 or 65 horse, i think your missing the point that it will still be 60+ horse per shot. a 1-5 gain heating the bottle to the optimum temp is kinda silly when your still getting 60 + horsepower. nice chart though

that's a gain when you heat it from 60 to 80 degrees. I wish that chart showed the amount of gain from a 30 degree bottle to a 80 degree bottle. I'm betting it's dramatic

 

[yamahajunkie]

boy thats not as cold as a filled bottle. i freeze my bottle or throw it in a snow bank, then fill from a mother bottle that is at room temp or so, install and comense the nitrous runs. strangley enough when i hit the button it works every time.

 

[yamahajunkie]

guess you cant race till the filled bottle is up to temp :ORC

 

[dirkdiggler]

boy thats not as cold as a filled bottle. i freeze my bottle or throw it in a snow bank, then fill from a mother bottle that is at room temp or so, install and comense the nitrous runs. strangley enough when i hit the button it works every time.

Good for you

 

[yamahajunkie]

 

[NOS-PRO]

O.K., I will be doing the bottle heated or cold time runs tomorrow, to see what difference it will make. I have 2 bottles in the freezer right now, and will have 3 in the truck, (hope they don't blow the pressure discs....)

will inform you Saturday morning.

 

[NOS-PRO]

WIR 7/7/06 Temp 84, with 42% humidity, and a barometer reading of 29.30
Sunny conditions, and a headwind of 15-20mph all evening, till the humidity jumped up to 80%.
Tom, (MrSled) and his 2 brothers, Bob and Jr., along with Rich from Richmotorsports came down to watch the night of action. Great to see you guys again, and hope to have the SRX done so Tom can take the Apex/Attak for a rip down the track with me.

The great debate is over for me, as I tried a cold bottle against a hot bottle, and the results were just the opposite from what I would expect. Tom was amazed also to see a cold botlle get a quicker time than the hot bottle.........Yes, you heard me.

Now, this is with my system from Barry, and cannot be compared to the other systems, cause I cannot say what effect it will have on other brands, just that I have proof of what I have encountered with my sled. All nitrous runs were stabbing both the throttle and nitrous right off of the line.

1st 3 runs were with a hot bottle at 93.5 degrees, from being in the trailer all day in the sun.

1st run - lane 2, reaction .047
1.489 60ft - 6.475 1/8 @ 107.909mph - 10.264 1/4 @ 126.234mph

2nd run - lane 2, reaction .147
1.501 60ft - 6.377 1/8 @ 108.722mph - 10.155 1/4 @ 126.047mph

3rd run - lane 2, reaction .172
1.489 60ft - 6.679 1/8 @ 99.155mph - 10.840 1/4 @ 114.034mph (ran out of nitrous)

now the cold bottle at 45 degrees for the next 4 runs

1st run - lane 1, reaction -.107
1.484 60ft - 6.362 1/8 @ 107.472mph - 10.126 1/4 @ 127.215mph

2nd run - lane 1, reaction .078
1.493 60ft - 6.396 1/8 @ 109.226mph - 10.189 1/4 @ 126.528mph

3rd run - lane 1, reaction -.039
1.501 60ft - 6.477 1/8 @ 108.790mph - 10.234 1/4 @ 127.779mph

4th run - lane 1, reaction .021
1.497 60ft - 6.545 1/8 @ 103.725mph - 10.517 1/4 @ 119.770mph (ran out of nitrous)

As the bottle warmed up between runs, the times got slower with the 3rd run almost going over he centerline, so I lifted a little bit. This was unpredicted, as it should have been the other way around, but for a .03 difference from the best of 2 bottles, this will never be an issue for me again.

 

[yamahajunkie]

great to hear it doesnt matter with your kit either. you would think we need a heater for nitrous on a sled in the winter, but some kits are just made to run in the cold. gotta love the speeds!!!! way to go thanks for the test!!!!

 

[NOS-PRO]

Hey junkie, I wanted to find out for myself also, as if I could make some faster times with a warm bottle, which didn't matter on my system, it would be the difference between a 9 and a 10 second 1/4 mile.

I will try to get the hot/cold bottle results on the dyno also in a couple weeks.

 

[Black 1000]

Nice work Terry. I do believe some systems need bottle heat. As with yours and the one I ordered they do not. Thanks for takeing the time to test.

 

[dirkdiggler]

If you look at the chart above it clearly shows that beond 80 degrees you acctually lose power. It looks like your bottle was 93 degrees.

 

[NOS-PRO]

Black - Yes, the Nitrous Oxide Systems components I used to have, needed the bottle above 70 degrees to even produce power.

At the track, I hated warming the bottle, that is why I looked for systems that don't require heating the bottle.