Maximum Entropy?

Scott Stone

Scott Stone

New member
How does maximum entropy come into the garage cleaning environment, especially in high heat situations? Entropy is basically defined as, maximum dispersal of molecules achieves the least amount of energy. Since water can maintain a much higher heat under pressure, as soon as that pressure is released, the water goes into the state it must assume at the assigned temperature. Meaning, if a person is at sea level, pressure washing, as soon as the water leaves the nozzle, the water converts into steam, because of the high heat, and loses the cleaning force attributed to the pressure. http://www.thefreedictionary.com/entropy
 
Some of us experienced that first hand on the wand with Jim's of Crystal Cleaning Company. When he hit 300 degrees, the impact was reduced, not just in feeling if from the wand, but the gum was more difficult to remove.

I contacted an engineer from Spay Systems for a similar chart and got some information, but not what I was looking for, hence I shared the Nozzle Trivia Thread.
 
"I dont no" I turn on the heat, it gets hot ,I burn gum no problem.
 
Scott Stone said:
How does maximum entropy come into the garage cleaning environment, especially in high heat situations? Entropy is basically defined as, maximum dispersal of molecules achieves the least amount of energy. Since water can maintain a much higher heat under pressure, as soon as that pressure is released, the water goes into the state it must assume at the assigned temperature. Meaning, if a person is at sea level, pressure washing, as soon as the water leaves the nozzle, the water converts into steam, because of the high heat, and loses the cleaning force attributed to the pressure. http://www.thefreedictionary.com/entropy
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Thanks Scott. That answers my post from yesterday about the boiling point of water vs 300 degree water used in some parking garage cleaning. Liquid vs a gas as far as using pressure to clean. If you're using steam I think you'd need to recover the steam. Like a big distillation unit. Yes I'm kidding. But I wonder if the EPA in Northern CA is aware of what's being put into their air? Sounds like another government agency to create.
 
IndyExterior said:
Thanks Scott. That answers my post from yesterday about the boiling point of water vs 300 degree water used in some parking garage cleaning. Liquid vs a gas as far as using pressure to clean. If you're using steam I think you'd need to recover the steam. Like a big distillation unit. Yes I'm kidding. But I wonder if the EPA in Northern CA is aware of what's being put into their air? Sounds like another government agency to create.
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I made a post in the thread where you asked the question, it showed a graph of the relationship between pressure vs temp, but I guess the thread got terminated. I look for the graph again.
 
Nigel, that is something that I have discussed with Tony, Chris Shelton and some other people.

We went out at nite to try out Jim's rig at the DMV. It was 60 degrees outside but with the water in the ground at a warmer temperature filling the tank, Jim's machine hit either 312 or 315 degrees.

I tried to remove some gum and that gum is just like the gum here in Texas. It is baked into the pores of the concrete, probably been there for years and is very hard to get up.

During the Demo on Sunday Chris Shelton tried the Steam Valve on his Landa Pressure Washer and tried the gum but as the machine made more of steam compared to very hot water, the cleaning energy and impact seemed to dissipate along with our excitement. hahahahaha

Just kidding. It was a great demo and great round table.

We tried different temperatures and it looks like anything over 250 degrees just is not cleaning gum as good and starts to work slower.

There are so many variables it would take many more days of testing to come to a good conclusion but when I do put the thermometer into the outlet of my coil I will know what temperature water I really have coming out and I am also installing a steam valve with shutoff to more precisely hit the temperatures I am looking for. Then I can do some more accurate testing by knowing the temperature of the water, also test the temperature of the water at the end of 200' of 3/8" hose also.
 
This is something that has to be tried out, its too unpredictable - it would be interesting to see some controlled testing. With the super heated water, I would think at the speed it is coming out of the nozzle most of it would still be water when it hits the cement, then maybe it goes in and flashes to steam and has some super cleaning effect? Who knows? Anything over 212 is going to have the effect. I don't remember the spray gun feeling like less impact at higher temp in Vegas
 
tomtucson said:
This is something that has to be tried out, its too unpredictable - it would be interesting to see some controlled testing. With the super heated water, I would think at the speed it is coming out of the nozzle most of it would still be water when it hits the cement, then maybe it goes in and flashes to steam and has some super cleaning effect? Who knows? Anything over 212 is going to have the effect. I don't remember the spray gun feeling like less impact at higher temp in Vegas
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It felt lighter to me Tom. I think you need more than 6 gpm at those temps to see gum fly. There was one point where Jim Gamble made an adjustment when I was on the wand, I told him it was feeling lighter.

Remember water vapor has far less weight (droplet size) than water, so hot water at 200 deg through a pressure washer nozzle will have more impact than 300 deg water exiting the same pressure washer nozzle.

To harness the full effect of 300 deg water you need to adjust pressure downward and decrease nozzle spray angle.

It was great talking to you Thursday Tom, thank you for your input with my burner assembly.
 
This is another great thread.

Nigel, do you have a thermometer on your rig so you know exactly how hot the water is coming out of the coil either at the coil or at the hose reel?

It would be interesting to see how much heat loss there is from 100' and 200' of hose, also from the coil to the hose reel.
 
I guess it's a matter of how fast the water turns to steam. If its instantaneous, then the sidewalk will get less impact.
 
Christopher said:
This is another great thread.

Nigel, do you have a thermometer on your rig so you know exactly how hot the water is coming out of the coil either at the coil or at the hose reel?

It would be interesting to see how much heat loss there is from 100' and 200' of hose, also from the coil to the hose reel.
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Nada. I dont have a thermometer anywhere on the system, (I have a inferred thermometer that I shoot various points).

I need to get one, there never seems to be any in stock at envirospec.

But believe me it is hot, I was in for a surprise on Thursday when I played CSI (burner edition).

The builder put a 3.5 nozzle in one of my burner assemblies @ 140 psi, that translates to 4.14 gph (the other burner cleaner at startup and shut down, hence i though I had burner problems), .........I think it was to much for a 20" coil, Beckett recommends no more that 4 gph in a 20". I was told I had 3.25 nozzle with 140 psi with translates to 3.85 gph.

I also adjusted the rpm on the engine, with pump in bypass and generator suppling the power only for the burner fan, ignition off , engine speed was 3640 rpm, ..... when loaded (pump and generator) rpm dropped to 3450, I increased the unloaded speed to 3730rpm so that now when the pump is loaded I have 3550rpm engine speed, then I know I should be getting the full 8.5 gpm on the pump and generator supplies the full frequency/ power (measured the pulley and checked the ratio to insure I had the right sizes so pump would be spinning at 1750 rpm if motor was at 3600rpm)
 
810f250 said:
Nada. I dont have a thermometer anywhere on the system, (I have a inferred thermometer that I shoot various points).

I need to get one, there never seems to be any in stock at envirospec.

But believe me it is hot, I was in for a surprise on Thursday when I played CSI (burner edition).

The builder put a 3.5 nozzle in one of my burner assemblies @ 140 psi, that translates to 4.14 gph (the other burner cleaner at startup and shut down, hence i though I had burner problems), .........I think it was to much for a 20" coil, Beckett recommends no more that 4 gph in a 20". I was told I had 3.25 nozzle with 140 psi with translates to 3.85 gph.

I also adjusted the rpm on the engine, with pump in bypass and generator suppling the power only for the burner fan, ignition off , engine speed was 3640 rpm, ..... when loaded (pump and generator) rpm dropped to 3450, I increased the unloaded speed to 3730rpm so that now when the pump is loaded I have 3550rpm engine speed, then I know I should be getting the full 8.5 gpm on the pump and generator supplies the full frequency/ power (measured the pulley and checked the ratio to insure I had the right sizes so pump would be spinning at 1750 rpm if motor was at 3600rpm)
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Do you teach college math in your off time? :yikes: Sometimes you totally loose me when reading your posts and I have to go back a few times to catch the jist of what your saying. Reminds me of one of my college math teachers
 
Nigel, does your machine have a tach on it? If not then do you have a portable?
 
tomtucson said:
I guess it's a matter of how fast the water turns to steam. If its instantaneous, then the sidewalk will get less impact.
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As soon as the water exits the tip of the wand, it will be affected, because it will no longer be in the pressure vessel. In this case, the hose and coil is the pressure vessel. Try this, turn on the heater on your pressure washer. Have someone hold the gun, and put your hand in the flow of the water at the furthest point. At that point, how much pressure are you feeling, and how much heat are you feeling? Gradually move your hand towards the tip of the wand. Notice when you start feeling the heat from the gun. There is a very real possibility that you will not be able to feel the heat go up significantly until you can barely stand to hold your hand in the pressure.

This is part of the reason why I find it so amusing when I watch someone clean something without a surface cleaner, holding the wand 2 feet from something, thinking that the pressure is helping to clean whatever it is.
 
True Scott! You can pretty much mist someone down with water thats leaving the gun at 200 deg! But, in that first 2 inches, whats going on and what effect is it having? I dont think anyone knows really, one would need to do controlled trials and see what happens.
 
tomtucson said:
True Scott! You can pretty much mist someone down with water thats leaving the gun at 200 deg! But, in that first 2 inches, whats going on and what effect is it having? I dont think anyone knows really, one would need to do controlled trials and see what happens.
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You have never been to Stone Labs?
 
Have you ever had your pressure water not shut off the heater and super heat the water? There is a lot of pressure that is built up in the hose, and a lot of heat. My experience has been that the water comes out like normal, until the line is cleared and then it is nothing but steam until the coil is cleared, and cooled down. I don't know what temperature the water is exiting the tip out, but there is not a lot of cleaning force behind it.
 
Scott Stone said:
Have you ever had your pressure water not shut off the heater and super heat the water?
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Don't you mean "Have you ever had your pressure water not shut off the heater and super heat the water!!!!!!!!:eek::shocked2::yikes:?
 
Chris Tharpe said:
Do you teach college math in your off time? :yikes: Sometimes you totally loose me when reading your posts and I have to go back a few times to catch the jist of what your saying. Reminds me of one of my college math teachers
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I have no ill intention Chris, I dont have a college degree. Getting a grasp of the science behind things of interest is just my nature i guess.
 
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