Den Pressure - A Definable Hypothesis & Experiments (Scepti, iWitness)

Would den pressure actually expect a weight loss in a compressor though if there is no expansion?

Quote from: Rayzor on August 04, 2016, 06:38:23 PM

Quote from: crutonius on August 04, 2016, 01:11:56 PM

Enough talk!  Let's science!!

Here we see my compressor at 0 psi weighing 52.8lb:


Here we see it at 120psi weighing in at 54.3lb:


Discuss!

Simple.   Just apply  PV = nRT,    since  Volume,Temperature and R ( assuming ideal gas laws and no phase changes)  are constant only n and P change and they change in linear fashion,   so converting from psig to psia,  the pressure has risen from 14.7 to 134.7 or 9.16 times, so the amount of air in the volume V is 9.16 times. The density of air is 0.0765 lbs/ft³  so  Weight change = V*0.0765*9.16 - V*0.0765  = V*0.624 lbs

Since crutonius didn't tell us the volume V,  (jroa derailed that discussion)  but he did tell us the weight change, so we can backtrack for an estimate of his compressor volume    deltaW = 54.2 - 52.8 = 1.4lbs = V*0.624,   V = 1.4/0.624 = 2.2 cu ft

So what is the actual compressor tank volume?  How close is close enough for a proof?

There will be a temperature change caused by compression,  but given the thermal mass of the steel tank I'd expect it to only contribute a few extra psi to the pressure gage.

PS.  When is America going to join the rest of the world and adopt the metric system!!!

Nice math. My compressor is 17 gallons. Which equals 2.273 cubic feet, very close indeed.

Regarding a proof or disproof of denpressure it's not how much weight gains there was. It's that there was any at all. In fact denpressure predicted that the weight should decrease.

I do share your frustration with the Imperial system. But that's the country I'm in.

That's closer than I was expecting.   2.2 predicted,  2.273 actual.      I'm calling that a failure for denspressure.  Feel free to speak up if you disagree.

Where did Scepti go? I suppose he's more keen on thought experiments. Actual science with data proving him wrong doesn't interest him. Still waiting on an FE believer to give their interpretation  of the results.

Moving right along since I still have my air compressor out, experiment 1:

The pressure is set at 150psi.  The distance between the nozzle and the surface is 2 feet.

One piece of steel weighing in at 3.051lb

Apply air, 3.133

One piece of wood weighing in at .048lb

Apply air, 12.8


And now we soak it overnight for, reasons:

Moving right along since I still have my air compressor out, experiment 1:

The pressure is set at 150psi.  The distance between the nozzle and the surface is 2 feet.

One piece of steel weighing in at 3.051lb

Apply air, 3.133

One piece of wood weighing in at .048lb

Apply air, 12.8


And now we soak it overnight for, reasons:

As I understand it, denpressure theory states the metal object should experience greater weight gain. Well it's weight increased by around 10%

The wood, however, weighed around 25 times the original weight.

Denpressure: 0

Gravity: 2

Denpressure: 0

Gravity: 2

The ideal gas laws are all that's required to understand and quantify these experiments,   they are extremely well known and date back to the 1830's,   and for anyone interested the ideal gas laws can be derived completely from first principles ( only minimal assumptions ) using the kinetic theory of gases.

Back to the balloon experiment,  I have an easier and more direct method that anyone can easily apply. 

Get a long straight  stick and find the balance point using a knife edge,  mark that point,   now get another stick a little less than half the length of the first.  Use it to mark off equal distances from the center balance point.  Mark those points and now tie short equal length pieces of fishing line to those two points.   Get two balloons and with both un-inflated tie the balloons to the fishing lines, check that it still balances perfectly,  if not adjust the center support point till it balances exactly. 

Now inflate just one of the balloons,  with a bicycle pump or similar,   place back on the knife edge and see if the inflated balloon is heavier or not.  This method eliminates the need for precision scales.   You could now add small weights to the lighter side to see how much is required to balance it,  maybe grains of rice?

Instead of a knife edge you could hang the thing from the roof with fishing line.

Wow, is your compressor bigger than mine?

Derailing attempt #1: 0 out of 10!

Quote from: TheRealBillNye on August 04, 2016, 01:38:03 PM

Quote from: jroa on August 04, 2016, 01:14:19 PM

Wow, is your compressor bigger than mine?

I dunno, how big is your compressor? What does it have to do with the topic, anyway?

You seem to be trying to impress us.  How big is yours?

Derailing attempt #2: 2 out of 10! - getting better!

Quote from: TheRealBillNye on August 04, 2016, 01:43:54 PM

Quote from: jroa on August 04, 2016, 01:40:16 PM

Quote from: TheRealBillNye on August 04, 2016, 01:38:03 PM

Quote from: jroa on August 04, 2016, 01:14:19 PM

Wow, is your compressor bigger than mine?

I dunno, how big is your compressor? What does it have to do with the topic, anyway?

You seem to be trying to impress us.  How big is yours?

You seem to be ignoring the results of the study.

Which study measured the size of any of our air compressors? 

Derailing attempt #3: 3 out of 10! - Trying harder!

The ideal gas laws are all that's required to understand and quantify these experiments,   they are extremely well known and date back to the 1830's,   and for anyone interested the ideal gas laws can be derived completely from first principles ( only minimal assumptions ) using the kinetic theory of gases.

I know of these experiments. It was fun watching the FE believers nod along, agreeing with all the procedures, expecting a different result from a centuries old experiment. This forum is very entertaining.

Seems to be some poor sportsmanship in this thread.  Sorry if I brought that on.

Derailing attempt #4: 5 out of 10! - You got a reaction, but still need to get better at this derailing!

So, which part of my statements do you disagree with? 

Derailing attempt #5: 5 out of 10! - Now you're starting to divert attention from any real discussion!

I am guessing Scepti is regrouping and evaluating the data before he replies.

My guess he will dismiss the results for some unproven reason.

This is why FE's tend to stick to thought experiments, things like zooming in and out on ships near the horizon and claiming pictures from NASA are fake.

I am guessing Scepti is regrouping and evaluating the data before he replies.

He is in the UK,  so it's a bit early to be up and about.   

I really like your no nonsense approach, just do it and stfu. I am heterosexual, but I am working a little bit of a man crush lol.

Here are the results of Experiment #3 the balloon experiment

Balloon before inflation.


Balloon Inflated.


Balloon after deflation.


So the inflated balloon weighed heavier by 0.544 grams after inflation.

The difference between before and after inflation, might be some residual humidity left in the balloon?   But only 0.113 grams  it doesn't change the result.

My prediction was for the inflated balloon to be heavier by about 1 gram,  but that depended almost entirely on the elasticity of the balloon material to determine what the pressure was inside the balloon.   

Denspressure predicted a loss of weight, the experiment clearly showed a weight gain,  so I call that a fail for denspressure theory.

Quote from: sceptimatic on August 04, 2016, 03:32:26 PM

Quote from: Jane on August 04, 2016, 03:28:41 PM

Quote from: sceptimatic on August 04, 2016, 03:17:18 PM

How much of that excess weight is water?

Yep, and this is another good reason why a balloon's a better example: transparency. We'd generally be able to see it's the same balloon, and usually be able to see if anything else is in it.

That's right. It's not as simple as 123 these experiments, are they?

I'm not sure the presence of humidity invalidates the experiment.  Whatever humidity in the tank is also present in the air around it.  Wouldn't that cancel out any effect humidity might have?

It's tricky because we're dealing with a huge energy source which is also agitating the atmosphere amid this humidity and yet that very same atmosphere has been super compressed inside a tank and under much less agitation.
It's a real tricky experiment.

Quote from: crutonius on August 04, 2016, 04:08:35 PM

Quote from: sceptimatic on August 04, 2016, 03:32:26 PM

Quote from: Jane on August 04, 2016, 03:28:41 PM

Quote from: sceptimatic on August 04, 2016, 03:17:18 PM

How much of that excess weight is water?

Yep, and this is another good reason why a balloon's a better example: transparency. We'd generally be able to see it's the same balloon, and usually be able to see if anything else is in it.

That's right. It's not as simple as 123 these experiments, are they?

I'm not sure the presence of humidity invalidates the experiment.  Whatever humidity in the tank is also present in the air around it.  Wouldn't that cancel out any effect humidity might have?

It's tricky because we're dealing with a huge energy source which is also agitating the atmosphere amid this humidity and yet that very same atmosphere has been super compressed inside a tank and under much less agitation.
It's a real tricky experiment.

Yet we know divers compressed air bottles are heavier when full.

I've gone ahead and updated Experiment 3 with the Balloon Hypothesis.  I was very busy at work today and skimmed the thread and only halfway understand the experiment so If there is some information that needs more clearly defined please feel free to PM me.  I don't want it getting lost in the pages.

Also I'd encourage everyone to do all the experiments if possible.  I'm not sure if I can accurately do number 1, even with a compressor so it might be up to others to test.

I understand that number 2 could result in some issues with floating.  Would a weight to hold the object down and water covering both the object and weight to the same volume level in each container make the test inaccurate?  (Assuming the same weight is used in each test).

Number 2 might be helped of someone could put the floating item in a pressurise chamber of water to force the water into the item (wood for instance) and then see how much further it sinks.
The chamber would mimic a depth of water pressure upon the item and would save adding a weight to allow the item to have it's atmosphere squeezed out.

Maybe babyhighspeed might have something like this.
If not, the weight will suffice as it should start to show something.

Would den pressure actually expect a weight loss in a compressor though if there is no expansion?

No. And this is the massive problem with experiments like this.
I'm actually open to any experiment done though just to see all of the results and to see where it all ties in or doesn't if that ends up the case.

I think it's going to be a mass thought on the best ways to actually show definitive results, but if we are all trying to solve a puzzle, we can all look for the relevant pieces like we are doing and see if we can find better fitting one's as we go along.


I'm 100% sure on this so I'm going to make sure that I fight for it all the way.

Here are the results of Experiment #3 the balloon experiment

Balloon before inflation.


Balloon Inflated.


Balloon after deflation.


So the inflated balloon weighed heavier by 0.544 grams after inflation.

The difference between before and after inflation, might be some residual humidity left in the balloon?   But only 0.113 grams  it doesn't change the result.

My prediction was for the inflated balloon to be heavier by about 1 gram,  but that depended almost entirely on the elasticity of the balloon material to determine what the pressure was inside the balloon.   

Denspressure predicted a loss of weight, the experiment clearly showed a weight gain,  so I call that a fail for denspressure theory.

There's no fail. There's nothing conclusive at all.

Quote from: sceptimatic on August 05, 2016, 01:15:53 AM

Quote from: crutonius on August 04, 2016, 04:08:35 PM

Quote from: sceptimatic on August 04, 2016, 03:32:26 PM

Quote from: Jane on August 04, 2016, 03:28:41 PM

Quote from: sceptimatic on August 04, 2016, 03:17:18 PM

How much of that excess weight is water?

Yep, and this is another good reason why a balloon's a better example: transparency. We'd generally be able to see it's the same balloon, and usually be able to see if anything else is in it.

That's right. It's not as simple as 123 these experiments, are they?

I'm not sure the presence of humidity invalidates the experiment.  Whatever humidity in the tank is also present in the air around it.  Wouldn't that cancel out any effect humidity might have?

It's tricky because we're dealing with a huge energy source which is also agitating the atmosphere amid this humidity and yet that very same atmosphere has been super compressed inside a tank and under much less agitation.
It's a real tricky experiment.

Yet we know divers compressed air bottles are heavier when full.

Why wouldn't they be?

Quote from: sandmanMike on August 04, 2016, 05:14:34 PM

I've gone ahead and updated Experiment 3 with the Balloon Hypothesis.  I was very busy at work today and skimmed the thread and only halfway understand the experiment so If there is some information that needs more clearly defined please feel free to PM me.  I don't want it getting lost in the pages.

Also I'd encourage everyone to do all the experiments if possible.  I'm not sure if I can accurately do number 1, even with a compressor so it might be up to others to test.

I understand that number 2 could result in some issues with floating.  Would a weight to hold the object down and water covering both the object and weight to the same volume level in each container make the test inaccurate?  (Assuming the same weight is used in each test).

Number 2 might be helped of someone could put the floating item in a pressurise chamber of water to force the water into the item (wood for instance) and then see how much further it sinks.
The chamber would mimic a depth of water pressure upon the item and would save adding a weight to allow the item to have it's atmosphere squeezed out.

Maybe babyhighspeed might have something like this.
If not, the weight will suffice as it should start to show something.

I have a few different presses ranging from 50 tons to over 50k. Perhaps build a metal water tight chamber and press the top down? That is what first comes to mind.

The fuel systems I work with , the tanks are pressurized, but only to about 40 psi, high volume of flow, but low pressure. I don't know if that would be enough pressure to perform the test?

These are things that first come to mind of available items.

This is for liquid...i have equipment for pressurising gas. I also have a machine that can create a gaseous smoke like dye. If that curbs anyone's creative thought process.

Quote from: sceptimatic on August 05, 2016, 01:24:37 AM

Quote from: sandmanMike on August 04, 2016, 05:14:34 PM

I've gone ahead and updated Experiment 3 with the Balloon Hypothesis.  I was very busy at work today and skimmed the thread and only halfway understand the experiment so If there is some information that needs more clearly defined please feel free to PM me.  I don't want it getting lost in the pages.

Also I'd encourage everyone to do all the experiments if possible.  I'm not sure if I can accurately do number 1, even with a compressor so it might be up to others to test.

I understand that number 2 could result in some issues with floating.  Would a weight to hold the object down and water covering both the object and weight to the same volume level in each container make the test inaccurate?  (Assuming the same weight is used in each test).

Number 2 might be helped of someone could put the floating item in a pressurise chamber of water to force the water into the item (wood for instance) and then see how much further it sinks.
The chamber would mimic a depth of water pressure upon the item and would save adding a weight to allow the item to have it's atmosphere squeezed out.

Maybe babyhighspeed might have something like this.
If not, the weight will suffice as it should start to show something.

I have a few different presses ranging from 50 tons to over 50k. Perhaps build a metal water tight chamber and press the top down? That is what first comes to mind.

The fuel systems I work with , the tanks are pressurized, but only to about 40 psi, high volume of flow, but low pressure. I don't know if that would be enough pressure to perform the test?

These are things that first come to mind of available items.

You've seen fence posts that are under pressure treatment, right?
Now we know that the pressure treatment they get forces the preservative through the pores of the wood to a certain depth. But even under that pressure there is still a lot of atmosphere trapped within that wood.
However, the wood comes out super heavy.

So realistically if we can use a small block of wood of say, something like 2x2x2 inches and put it under decent pressure in a strong but small enough chamber of water, weighing it beforehand then after, whilst also seeing what that weight is against a few items of equal size, of different densities.

Quote from: Rayzor on August 05, 2016, 01:10:05 AM

Here are the results of Experiment #3 the balloon experiment

Balloon before inflation.


Balloon Inflated.


Balloon after deflation.


So the inflated balloon weighed heavier by 0.544 grams after inflation.

The difference between before and after inflation, might be some residual humidity left in the balloon?   But only 0.113 grams  it doesn't change the result.

My prediction was for the inflated balloon to be heavier by about 1 gram,  but that depended almost entirely on the elasticity of the balloon material to determine what the pressure was inside the balloon.   

Denspressure predicted a loss of weight, the experiment clearly showed a weight gain,  so I call that a fail for denspressure theory.

There's no fail. There's nothing conclusive at all.

I'll wait for a few more experimental results to come in,  but unless you can predict, calculate and explain the experimental results,  then denspressure theory is in deep trouble. 

Quote from: inquisitive on August 05, 2016, 01:21:52 AM

Quote from: sceptimatic on August 05, 2016, 01:15:53 AM

Quote from: crutonius on August 04, 2016, 04:08:35 PM

Quote from: sceptimatic on August 04, 2016, 03:32:26 PM

Quote from: Jane on August 04, 2016, 03:28:41 PM

Quote from: sceptimatic on August 04, 2016, 03:17:18 PM

How much of that excess weight is water?

Yep, and this is another good reason why a balloon's a better example: transparency. We'd generally be able to see it's the same balloon, and usually be able to see if anything else is in it.

That's right. It's not as simple as 123 these experiments, are they?

I'm not sure the presence of humidity invalidates the experiment.  Whatever humidity in the tank is also present in the air around it.  Wouldn't that cancel out any effect humidity might have?

It's tricky because we're dealing with a huge energy source which is also agitating the atmosphere amid this humidity and yet that very same atmosphere has been super compressed inside a tank and under much less agitation.
It's a real tricky experiment.

Yet we know divers compressed air bottles are heavier when full.

Why wouldn't they be?

It's impossible for air pressure to know the tank is full and that it need to provide more force.

Quote from: crutonius on August 04, 2016, 04:08:35 PM

Quote from: sceptimatic on August 04, 2016, 03:32:26 PM

Quote from: Jane on August 04, 2016, 03:28:41 PM

Quote from: sceptimatic on August 04, 2016, 03:17:18 PM

How much of that excess weight is water?

Yep, and this is another good reason why a balloon's a better example: transparency. We'd generally be able to see it's the same balloon, and usually be able to see if anything else is in it.

That's right. It's not as simple as 123 these experiments, are they?

I'm not sure the presence of humidity invalidates the experiment.  Whatever humidity in the tank is also present in the air around it.  Wouldn't that cancel out any effect humidity might have?

It's tricky because we're dealing with a huge energy source which is also agitating the atmosphere amid this humidity and yet that very same atmosphere has been super compressed inside a tank and under much less agitation.
It's a real tricky experiment.

I have to point this out and I hope it doesn't come off as snarky. It's not a tricky experiment for those of us that modeled it after basic physics. It's actually pretty straight forward. You might have noticed a few posts ago rayzer correctly calculated the size of tank even though I didn't include that in the original data.

As for humidity we can rule that out as I've drained the tank afterwards and there was less than an ounce of water.

What other factors do you believe might have caused this experiment to produce results which are incompatible with denpressure?

Wow this is pretty pathetic

Before experiments were conducted Scepti had no problems with the setup or the theory behind each experiment. Now that the results are different from what he expected, he rejects the findings. He doesn't even say why. He just says "these tests are tricky" or "that's inconclusive" without providing any insight as to how we could improve the experiment.

Face it, scepti. Your theory has no leg to stand on. You are in denial.

Wow this is pretty pathetic

Before experiments were conducted Scepti had no problems with the setup or the theory behind each experiment. Now that the results are different from what he expected, he rejects the findings. He doesn't even say why. He just says "these tests are tricky" or "that's inconclusive" without providing any insight as to how we could improve the experiment.

Face it, scepti. Your theory has no leg to stand on. You are in denial.

Just as I predicted earlier in this thread when he stopped posting for a short time. 

This is not the first or the last time he will do this. 

@scepti

If you are truly searching for answers you need to go back to the drawing board and rethink your model.  If not you will just continue going down the wrong path resulting in never finding the right answer.

Lets just assume you are right and gravity does not exist.  How will you be able to put the puzzle together if you ignore things that says your current model is wrong? 

To advance you can not only look at what says you are right, but you need to accept things that say you are wrong.  When observations say you are wrong then you adjust and start looking at things from another angle.