Speculations on the witness's evidence
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eccentrically1
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re: Speculations on the witness's evidence
My reply to Jim's comments are in blue:
You have to be kidding! The water screw is the most speculative of all the loads applied to the wheel. Its dimensions can only be derived by scaling Bessler's pictures. And as I stated in my last post, a water screw has a lot more friction than a simple rope over two pulleys.
It is true that the dimensions of the water screw are derived from Bessler's scale drawing. Why is that now not good enough when you seem quite happy to use those same drawings to derive other dimensions? Who's kidding who?
It is not true that the water screw is the most speculative of all the applied loads. We know it's size from the scale drawing, we know it's speed was about 10 RPM when driven by the wheel, we know it's approximate pump rate based on simple calculation (I even assumed your own flow rate overestimate). The fact is an archimedes water screw performance is not some unknown science fiction, it is well trodden ground.
With the water screw you have a very inefficient square pulley and rope drive system. There would have been a lot of rubbing of the rope on the square pulleys. The weight of the screw itself without any water would have been significant and thus produce significant friction on its bearings. Then adding the weight of the water would have produced even more friction. All of this weight of the water and the screw was supported by the two end bearings of the water screw. Add to this the sideways pulling of the rope and you get even more force on the bearing producing even more friction. Then add the churning of the water by the screwing of the pumps and you get yet more friction. The bottom line is that pumping water with a Archimedes screw is very inefficient and consumes a lot more energy than just the water lifting.
It is not true that the square pulley rope drive is very inefficient. At the low operating speed of the screw it is a relatively efficient power transfer. Try it.
Bearing friction would have been significant, but this is moderated by the very low 10 RPM operating speed of the pump. Losses through churning of the water is proportional to speed and is likewise moderated by the very low operating speed of the pump. The bottom line is that your consistent overestimates of losses is not realistic under the specific operating conditions and known performance of this kind pump of pump.
So don't give me this BS about lifting of weights (hammers and hundred weight) being more speculative and anecdotal than the water screw. It is the water screw that is much more speculative simply because its dimensions and thus its lifting weight are unknown. It also has much more friction. You also base some of your assumptions on a 'more than fourfold reduction' statement, which is a reference to the "Peritrochium" (Axis in Peritrochio) effect which Bessler explains.
Wolff described the 4 x lift reduction applied to the 60 lb being lifted by the Merseburg wheel. Wolff never explained it in terms of "Peritrochium" at all, that is your elaboration on Bessler's ramblings.
The bottom line is that the simple lifting of 112 pounds (hundred-weight) by way of a rope wrapped around the 8 inch wooden axle turning at a wheel speed of 26 RPM, which was the witnessed approximate turning speed of the wheel, produces a calculated wheel output of 138 Watts. This is the least speculative of all. And if by chance the wheel did slow down when lifting the hundred-weight, even though there was no witness of any such a slowing down when lifting the weight, the output at 20 RPM would still be 106 Watts. This is a four to five times greater than your purely highly speculative 25 Watts.
The bottom line is that no witness described the Kassel wheel lifting a hundred-weight while it maintained it's free running speed of 26 RPM. You made it up! In fact there is no independent witness measurement available that indicates what was lifted, how it was lifted, and the performance of the wheel under such a load. If Wagner is to be believed then no such feat occurred!
Do a calculation of the lifting of the hammer mill weights. They agree rather closely with the lifting of the hundred-weight.
How can I calculate the lifting of the hammer weights without knowing the lift height of the hammers? Your calculation only agrees closely with the hundred-weight lift assumption if you use your own stamper lift height assumption. Assumption supporting assumption!
It makes very good sense. The water screw had a very large amount of unknown friction. And the screw dimensions are highly speculative. There is no known statement as to the dimensions of the screw. All we have is the drawing. A simple increase of one inch to the screw radius adds about 30 percent to its work load. I put very little weight on any water screw calculation simply because of their highly speculative nature.
Bessler's scale drawing indicates the screw pump radius was about 9.5 inches. If you think an increase of 1 inch radius to 10.5 inches (which would be inconsistent with Bessler's scale drawing) would increase work load by 30% then you clearly still do not understand how a water screw works.
On the other hand we do have statements as to the dimensions of the hammers and the lifting of the hundred-weight load. Because the hundred-weight lifting took only about ten rotations lasting about 23 seconds, it was difficult to measure any slow down of the wheel produced by such a demonstration.
We do not have statements about the lift height of the hammers. We do not have statements about how the wheel performed under the supposed hundred-weight load. Where is the statement that the supposed hundred-weight lift lasted 23 seconds - you made it up!
Yes, there is always the possibility that the wooden hammers were hollowed out making them lighter than they looked. But then you must assume Bessler to be dishonest.
I do not think the hammers were hollow. But in order to calculate power we need to know more than their weight, we need to know the height they were lifted and the frequency they were lifted - of which we do not have any eyewitness statements. I do not assume Bessler was dishonest but I do assume that his marketing strategy was designed to give him an advantage. Some things have not changed in 300 years.
There are just way too many unknown factors involved with the water screw to be able to calculate a realistic or reliable load value for it. I'll eventually get around to calculating the water screw, but it is very low priority simply because I know that there is no way to determine the friction involved, there is no stated dimensions for the screw, and I know that a water screw involves a very large amount of wasted friction making any calculation highly speculative.
Already been covered.
Each one of us is free to make our own conclusions. I conclude that the output of the Kassel (4th) wheel was at least 100 Watts and most likely produced more than 130 Watts when friction and peak load is considered. I base it upon known stated wheel data involving the simple straight-forward lifting of known weight, and not on unknown speculations involving the water screw.
I think it is unwise to make any conclusions based on our present limited data. However, I do think there are indications that the wheel was much less powerful than Bessler's marketing spin might lead us to believe.
Wagner appeared incensed by the discrepancy between what Bessler said about the power of his wheel and what was actually demonstrated and contends the wheel was much less powerful than promoted. Wolff's description of the Merseburg wheel 60 lb lift reduction suggests the wheel was less powerful than promoted. Leibniz's comment that the wheel was of little practical value in it's current form because it "could not do anything" suggests the wheel was less powerful than promoted. Karl's apparent lack of interest in buying and/or practically implementing Bessler's wheel seems to suggest the wheel was less powerful than promoted (why would Karl think anyone might be interested in buying a wheel that he had rejected?). I could go on.
Bill, I hope I've stated my case clearly. You can choose to disagree, but the known facts support my conclusions.
Jim, the known facts can't support any conclusions at all. But they can point us in the right direction.
You have to be kidding! The water screw is the most speculative of all the loads applied to the wheel. Its dimensions can only be derived by scaling Bessler's pictures. And as I stated in my last post, a water screw has a lot more friction than a simple rope over two pulleys.
It is true that the dimensions of the water screw are derived from Bessler's scale drawing. Why is that now not good enough when you seem quite happy to use those same drawings to derive other dimensions? Who's kidding who?
It is not true that the water screw is the most speculative of all the applied loads. We know it's size from the scale drawing, we know it's speed was about 10 RPM when driven by the wheel, we know it's approximate pump rate based on simple calculation (I even assumed your own flow rate overestimate). The fact is an archimedes water screw performance is not some unknown science fiction, it is well trodden ground.
With the water screw you have a very inefficient square pulley and rope drive system. There would have been a lot of rubbing of the rope on the square pulleys. The weight of the screw itself without any water would have been significant and thus produce significant friction on its bearings. Then adding the weight of the water would have produced even more friction. All of this weight of the water and the screw was supported by the two end bearings of the water screw. Add to this the sideways pulling of the rope and you get even more force on the bearing producing even more friction. Then add the churning of the water by the screwing of the pumps and you get yet more friction. The bottom line is that pumping water with a Archimedes screw is very inefficient and consumes a lot more energy than just the water lifting.
It is not true that the square pulley rope drive is very inefficient. At the low operating speed of the screw it is a relatively efficient power transfer. Try it.
Bearing friction would have been significant, but this is moderated by the very low 10 RPM operating speed of the pump. Losses through churning of the water is proportional to speed and is likewise moderated by the very low operating speed of the pump. The bottom line is that your consistent overestimates of losses is not realistic under the specific operating conditions and known performance of this kind pump of pump.
So don't give me this BS about lifting of weights (hammers and hundred weight) being more speculative and anecdotal than the water screw. It is the water screw that is much more speculative simply because its dimensions and thus its lifting weight are unknown. It also has much more friction. You also base some of your assumptions on a 'more than fourfold reduction' statement, which is a reference to the "Peritrochium" (Axis in Peritrochio) effect which Bessler explains.
Wolff described the 4 x lift reduction applied to the 60 lb being lifted by the Merseburg wheel. Wolff never explained it in terms of "Peritrochium" at all, that is your elaboration on Bessler's ramblings.
The bottom line is that the simple lifting of 112 pounds (hundred-weight) by way of a rope wrapped around the 8 inch wooden axle turning at a wheel speed of 26 RPM, which was the witnessed approximate turning speed of the wheel, produces a calculated wheel output of 138 Watts. This is the least speculative of all. And if by chance the wheel did slow down when lifting the hundred-weight, even though there was no witness of any such a slowing down when lifting the weight, the output at 20 RPM would still be 106 Watts. This is a four to five times greater than your purely highly speculative 25 Watts.
The bottom line is that no witness described the Kassel wheel lifting a hundred-weight while it maintained it's free running speed of 26 RPM. You made it up! In fact there is no independent witness measurement available that indicates what was lifted, how it was lifted, and the performance of the wheel under such a load. If Wagner is to be believed then no such feat occurred!
Do a calculation of the lifting of the hammer mill weights. They agree rather closely with the lifting of the hundred-weight.
How can I calculate the lifting of the hammer weights without knowing the lift height of the hammers? Your calculation only agrees closely with the hundred-weight lift assumption if you use your own stamper lift height assumption. Assumption supporting assumption!
It makes very good sense. The water screw had a very large amount of unknown friction. And the screw dimensions are highly speculative. There is no known statement as to the dimensions of the screw. All we have is the drawing. A simple increase of one inch to the screw radius adds about 30 percent to its work load. I put very little weight on any water screw calculation simply because of their highly speculative nature.
Bessler's scale drawing indicates the screw pump radius was about 9.5 inches. If you think an increase of 1 inch radius to 10.5 inches (which would be inconsistent with Bessler's scale drawing) would increase work load by 30% then you clearly still do not understand how a water screw works.
On the other hand we do have statements as to the dimensions of the hammers and the lifting of the hundred-weight load. Because the hundred-weight lifting took only about ten rotations lasting about 23 seconds, it was difficult to measure any slow down of the wheel produced by such a demonstration.
We do not have statements about the lift height of the hammers. We do not have statements about how the wheel performed under the supposed hundred-weight load. Where is the statement that the supposed hundred-weight lift lasted 23 seconds - you made it up!
Yes, there is always the possibility that the wooden hammers were hollowed out making them lighter than they looked. But then you must assume Bessler to be dishonest.
I do not think the hammers were hollow. But in order to calculate power we need to know more than their weight, we need to know the height they were lifted and the frequency they were lifted - of which we do not have any eyewitness statements. I do not assume Bessler was dishonest but I do assume that his marketing strategy was designed to give him an advantage. Some things have not changed in 300 years.
There are just way too many unknown factors involved with the water screw to be able to calculate a realistic or reliable load value for it. I'll eventually get around to calculating the water screw, but it is very low priority simply because I know that there is no way to determine the friction involved, there is no stated dimensions for the screw, and I know that a water screw involves a very large amount of wasted friction making any calculation highly speculative.
Already been covered.
Each one of us is free to make our own conclusions. I conclude that the output of the Kassel (4th) wheel was at least 100 Watts and most likely produced more than 130 Watts when friction and peak load is considered. I base it upon known stated wheel data involving the simple straight-forward lifting of known weight, and not on unknown speculations involving the water screw.
I think it is unwise to make any conclusions based on our present limited data. However, I do think there are indications that the wheel was much less powerful than Bessler's marketing spin might lead us to believe.
Wagner appeared incensed by the discrepancy between what Bessler said about the power of his wheel and what was actually demonstrated and contends the wheel was much less powerful than promoted. Wolff's description of the Merseburg wheel 60 lb lift reduction suggests the wheel was less powerful than promoted. Leibniz's comment that the wheel was of little practical value in it's current form because it "could not do anything" suggests the wheel was less powerful than promoted. Karl's apparent lack of interest in buying and/or practically implementing Bessler's wheel seems to suggest the wheel was less powerful than promoted (why would Karl think anyone might be interested in buying a wheel that he had rejected?). I could go on.
Bill, I hope I've stated my case clearly. You can choose to disagree, but the known facts support my conclusions.
Jim, the known facts can't support any conclusions at all. But they can point us in the right direction.
Last edited by ovyyus on Wed Nov 09, 2011 10:27 pm, edited 2 times in total.
re: Speculations on the witness's evidence
Rope rubbing? only if it is slipping, and less likely than if on a round one! If it is/was slipping then none of your calculations based on speculation is going to be objective in the sense of having any actual existence?With the water screw you have a very inefficient square pulley and rope drive system. There would have been a lot of rubbing of the rope on the square pulleys
Ralph
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nicbordeaux
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What were they lowered and raised by, then ? Take an atwoods and it's initial purpose, it is fineley balanced and a very small amount of weight is added to one side to get that side to move downwards. If the stamper blocks are just a slightly modified incarnation of an atwoods, albeit with ropes over pulleys and maybe gearing via pulley wheel dia differences, the energy requirments are pretty close to zilch compared to a straight "no counter-balance" lift.eccentrically1 wrote:I think the stampers are different because they weren't lowered by the wheel.
Showmanship.
The "evidence" seems to point more and more to the wheel having very, very little power other than that conferred to it by the inertial characteristics of the large amounts of balanced mass moving around. Correspondingly, the energy input requirement would be piffling.
Shoot me down in flames, gimme the red star fairy if you want :-)
Edited to say that I am in absolute amazement and admiration upon re-reading my post.
If you think you have an overunity device, think again, there is no such thing. You might just possibly have an unexpectedly efficient device. In which case you will be abducted by MIB and threatened by aliens.
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eccentrically1
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Well, the stampers were raised by the little pegs on the axle I suppose and then dropped. Lowered by gravity. that's the way I understand it. If the wheel lowered them, they wouldn't stamp anything very well.
Regarding how high the stampers were lifted, Bill, wouldn't that be related to the diameter of the axle? And the frequency to the 26 rpm?I do not think the hammers were hollow. But in order to calculate power we need to know more than their weight, we need to know the height they were lifted and the frequency they were lifted - of which we do not have any eyewitness statements.
re: Speculations on the witness's evidence
Why any water screw calculations will always be highly speculative.
There are a number of variables which go into the calculate of the energy required to rotate Bessler's Archimedes screw. First there are a number of variable needed to calculate the volume of water lifted by a water screw. Second, there are a number of friction sources which values are unknown.
Screw Length.
The screw length must be derived by measuring the drawing.
Screw Internal diameter.
The screw internal diameter is unknown because we do not know the screw wall thickness. Thus it is a pure guess. A small change of this variable produces a very large change to the volume of water lifted. See note at end of post.
Screw Core shaft diameter
The screw core diameter can be derived by measuring the drawing.
Screw Slope.
The screw slope angle must be derived by measuring the drawing.
Screw Speed.
The screw speed must be derived by measuring the pulley ratios of the drawing.
Screw Vane spacing.
The screw vane spacing is almost totally unknown. The vane spacing (or lead) could be anything. The vane spacing determines how much water will fit inside each 'bucket' that is formed by the vane. We do not know if the vanes were spaced close together or far apart. Spacing makes a big difference in what percentage each bucket is filled.
Screw Vane count.
We don't know if it was a single vane pump or a multiple vane pump. It looks like a single vane pump because of the single notches at the ends, but that could be to make the drawing simple. Double lead screw pumps are much more common and are more efficient.
Screw Vane thickness.
The vane wall thickness is totally unknown. If the vane wall was thick then there was less room for the water. If the walls were thin then more water was in the screw.
Screw venting.
This aspect needs a little more investigation on my part. I'm concerned about the screw becoming a syphon which would inhibit its operation. A simple solution would be vent holes through the vanes at the core shaft. Such vents would be one of the limiting factors for how full the 'buckets' get filled. Or a screw can 'cup' a certain amount of water and air each rotation, but this method is not shown by Bessler.
Water Immersion level.
The amount of the screw that was above the water level must be measured from the picture. It is obvious that such a level could not be kept constant. If the tank was filled to overflowing when the screw begins to rotate then the water level will drop because water is pumped out of the tank and into the screw before being discharged. To determine how much the water drops you need to know the tank size, which must be scaled from the drawing. Then there is the problem of spillage and leakage which will lower the water level. This is plainly shown in the drawing where spilled water drains through the floor and then outside the building.
Friction of the water in the screw.
Churning of water produces friction. The water is churned by each vane as the water is lifted upward through the screw. The water must flow over the surface of each vane as it is lifted. The rough or smooth condition of the vanes would determine the friction. This friction would play a major roles in the overall friction of the screw.
Friction of the screw bearings.
The bottom bearing is in the water and cannot be lubricated. The bearings must support pressure in two direction, side ways and end ways. A big factor with bearing friction is always the weight load. Here we have the weight of the screw, which is very big and massive and unknown. Once pumping begins we also have the weight of the lifted water. Bearing friction is constant per rotation. Contrary to what Bill thinks, each rotation produces the same energy loss per rotation regardless of speed. Slower speed does not produce less friction. The bearings would have been a major source of friction. We know nothing about these bearings and thus cannot determine how much friction they produced.
Friction of the rope belt.
The screw is shown as being driven by a twisted rope belt on square pulleys. I have no idea why the pulleys were square. Square pulleys make no sense to me. Regardless, all pulleys produce friction. The rope belt rubs on the side flanges as the rope enters the pulley and then rubs again as it leaves the pulley groove. Twisting of the rope belt from the horizontal wheel axle to the sloped screw causes extensive rubbing of the rope belt on the sides of the pulleys. The amount of this friction is unknown.
CONCLUSION
The vast number of unknown variable factors involved with Bessler's Archimedes screw pump makes any attempt to calculate the power needed to drive it close to worthless because of the vast amount of unknown dimensional factors and the unknown friction factors.
The simple lifting of a known weight by wrapping of a rope around a known diameter of Bessler's wheel axle tuning at a known RPM speed with speculation that it might have slowed down is a vastly more accurate calculation.
The same goes for the lifting of the hammer weights which involves speculation as to the weight of the wood (different hardwoods have different weights) and speculation as to the actual lift height which must be scaled from the drawings.
There are a number of variables which go into the calculate of the energy required to rotate Bessler's Archimedes screw. First there are a number of variable needed to calculate the volume of water lifted by a water screw. Second, there are a number of friction sources which values are unknown.
Screw Length.
The screw length must be derived by measuring the drawing.
Screw Internal diameter.
The screw internal diameter is unknown because we do not know the screw wall thickness. Thus it is a pure guess. A small change of this variable produces a very large change to the volume of water lifted. See note at end of post.
Screw Core shaft diameter
The screw core diameter can be derived by measuring the drawing.
Screw Slope.
The screw slope angle must be derived by measuring the drawing.
Screw Speed.
The screw speed must be derived by measuring the pulley ratios of the drawing.
Screw Vane spacing.
The screw vane spacing is almost totally unknown. The vane spacing (or lead) could be anything. The vane spacing determines how much water will fit inside each 'bucket' that is formed by the vane. We do not know if the vanes were spaced close together or far apart. Spacing makes a big difference in what percentage each bucket is filled.
Screw Vane count.
We don't know if it was a single vane pump or a multiple vane pump. It looks like a single vane pump because of the single notches at the ends, but that could be to make the drawing simple. Double lead screw pumps are much more common and are more efficient.
Screw Vane thickness.
The vane wall thickness is totally unknown. If the vane wall was thick then there was less room for the water. If the walls were thin then more water was in the screw.
Screw venting.
This aspect needs a little more investigation on my part. I'm concerned about the screw becoming a syphon which would inhibit its operation. A simple solution would be vent holes through the vanes at the core shaft. Such vents would be one of the limiting factors for how full the 'buckets' get filled. Or a screw can 'cup' a certain amount of water and air each rotation, but this method is not shown by Bessler.
Water Immersion level.
The amount of the screw that was above the water level must be measured from the picture. It is obvious that such a level could not be kept constant. If the tank was filled to overflowing when the screw begins to rotate then the water level will drop because water is pumped out of the tank and into the screw before being discharged. To determine how much the water drops you need to know the tank size, which must be scaled from the drawing. Then there is the problem of spillage and leakage which will lower the water level. This is plainly shown in the drawing where spilled water drains through the floor and then outside the building.
Friction of the water in the screw.
Churning of water produces friction. The water is churned by each vane as the water is lifted upward through the screw. The water must flow over the surface of each vane as it is lifted. The rough or smooth condition of the vanes would determine the friction. This friction would play a major roles in the overall friction of the screw.
Friction of the screw bearings.
The bottom bearing is in the water and cannot be lubricated. The bearings must support pressure in two direction, side ways and end ways. A big factor with bearing friction is always the weight load. Here we have the weight of the screw, which is very big and massive and unknown. Once pumping begins we also have the weight of the lifted water. Bearing friction is constant per rotation. Contrary to what Bill thinks, each rotation produces the same energy loss per rotation regardless of speed. Slower speed does not produce less friction. The bearings would have been a major source of friction. We know nothing about these bearings and thus cannot determine how much friction they produced.
Friction of the rope belt.
The screw is shown as being driven by a twisted rope belt on square pulleys. I have no idea why the pulleys were square. Square pulleys make no sense to me. Regardless, all pulleys produce friction. The rope belt rubs on the side flanges as the rope enters the pulley and then rubs again as it leaves the pulley groove. Twisting of the rope belt from the horizontal wheel axle to the sloped screw causes extensive rubbing of the rope belt on the sides of the pulleys. The amount of this friction is unknown.
CONCLUSION
The vast number of unknown variable factors involved with Bessler's Archimedes screw pump makes any attempt to calculate the power needed to drive it close to worthless because of the vast amount of unknown dimensional factors and the unknown friction factors.
The simple lifting of a known weight by wrapping of a rope around a known diameter of Bessler's wheel axle tuning at a known RPM speed with speculation that it might have slowed down is a vastly more accurate calculation.
The same goes for the lifting of the hammer weights which involves speculation as to the weight of the wood (different hardwoods have different weights) and speculation as to the actual lift height which must be scaled from the drawings.
Note concerning screw radius verses volume:
Assuming a 2 inch radius core shaft and a change from an 8 inch internal radius to a 7 inch internal radius causes a 33% increase of the water volume.
8_inch_inside_radius ^ 2 × pi - 2_inch_shaft_radius ^ 2 × pi = 188.496_square_inch
7_inch_inside_radius ^ 2 × pi - 2_inch_shaft_radius ^ 2 × pi = 141.372_square_inch
188.496_square_inch ÷ 141.372_square_inch = 1.3333, which is a 33% increase of water within the screw.
My point being that a very small difference of assumed dimensions can make a very large difference in water volume.
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nicbordeaux
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As this is a thread (I think) about witness reports, I'd like to discuss the Ratchet Wench. The lass who split on Bessler sayig that an old man in a room next door was pulling a string. The objection to that one is obvious, and has been made : what the heck could an old man with a flimsy piece of string contribute ? In terms of direct drive, nada. However, if the "wheel" was using a ratchet system, as much "evidence" leads us to believe, a piece of string would easily engage or disengage a ratchet pawl. For continuous running it's unlikely, because the guy would need to get up for a pee from time to time. But for stopping the wheel running and starting it again if it was stopped in an "OB" position...
So, we now have a Socket Wench.
So, we now have a Socket Wench.
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eccentrically1
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re: Speculations on the witness's evidence
I had a perfectly wonderful reading, but this wasn't it!
re: Speculations on the witness's evidence
Screw Length.
The screw length must be derived by measuring the drawing.
It is a scaled drawing and the screw length is 12 feet.
Screw Internal diameter.
The screw internal diameter is unknown because we do not know the screw wall thickness. Thus it is a pure guess. A small change of this variable produces a very large change to the volume of water lifted. See note at end of post.
Hardly a "pure guess", the scale drawing indicates an outside diameter of close to 18 inches. Wall thickness is unknown, but probably quite thin because the inherent geometry of the screw does not require great material strength. An estimate of 1/4 inch wall thickness is probably close.
Screw Core shaft diameter
The screw core diameter can be derived by measuring the drawing.
It is about 2 inches diameter.
Screw Slope.
The screw slope angle must be derived by measuring the drawing.
20 degrees.
Screw Speed.
The screw speed must be derived by measuring the pulley ratios of the drawing.
About 10 RPM.
Screw Vane spacing.
The screw vane spacing is almost totally unknown. The vane spacing (or lead) could be anything. The vane spacing determines how much water will fit inside each 'bucket' that is formed by the vane. We do not know if the vanes were spaced close together or far apart. Spacing makes a big difference in what percentage each bucket is filled.
The scale drawing indicates vane spacing is about 2 feet.
Screw Vane count.
We don't know if it was a single vane pump or a multiple vane pump. It looks like a single vane pump because of the single notches at the ends, but that could be to make the drawing simple. Double lead screw pumps are much more common and are more efficient.
Drawing indicates single vane (it is also the easiest and lightest to construct).
Screw Vane thickness.
The vane wall thickness is totally unknown. If the vane wall was thick then there was less room for the water. If the walls were thin then more water was in the screw.
Once again the basic structure of the screw is quite strong and it would not require the use of heavy materials. I assume 1/4 inch vane thickness would not be far off.
Screw venting.
This aspect needs a little more investigation on my part. I'm concerned about the screw becoming a syphon which would inhibit its operation. A simple solution would be vent holes through the vanes at the core shaft. Such vents would be one of the limiting factors for how full the 'buckets' get filled. Or a screw can 'cup' a certain amount of water and air each rotation, but this method is not shown by Bessler.
Water Immersion level.
The amount of the screw that was above the water level must be measured from the picture. It is obvious that such a level could not be kept constant. If the tank was filled to overflowing when the screw begins to rotate then the water level will drop because water is pumped out of the tank and into the screw before being discharged. To determine how much the water drops you need to know the tank size, which must be scaled from the drawing. Then there is the problem of spillage and leakage which will lower the water level. This is plainly shown in the drawing where spilled water drains through the floor and then outside the building.
Water level does not change pump flow rate (unless it runs dry). As discussed in another thread there is no drain for "spillage and leakage". I have attached a crop of Bessler's drawing which plainly shows the drain is for emptying the water tank.
Friction of the water in the screw.
Churning of water produces friction. The water is churned by each vane as the water is lifted upward through the screw. The water must flow over the surface of each vane as it is lifted. The rough or smooth condition of the vanes would determine the friction. This friction would play a major roles in the overall friction of the screw.
The very low operating speed of the pump would limit churn to a relatively small loss.
Friction of the screw bearings.
The bottom bearing is in the water and cannot be lubricated. The bearings must support pressure in two direction, side ways and end ways. A big factor with bearing friction is always the weight load. Here we have the weight of the screw, which is very big and massive and unknown. Once pumping begins we also have the weight of the lifted water. Bearing friction is constant per rotation. Contrary to what Bill thinks, each rotation produces the same energy loss per rotation regardless of speed. Slower speed does not produce less friction. The bearings would have been a major source of friction. We know nothing about these bearings and thus cannot determine how much friction they produced.
The bottom bearing is very thin and lubricated by the tank water. The top bearing is open and would have been lubricated. Given that the overall construction of the screw was probably very light, due to the inherent strength of the structure, then bearing load (and friction loss) would be relatively minor. I have attached crops of the bearings indicated in Bessler's scale drawing.
Friction of the rope belt.
The screw is shown as being driven by a twisted rope belt on square pulleys. I have no idea why the pulleys were square. Square pulleys make no sense to me. Regardless, all pulleys produce friction. The rope belt rubs on the side flanges as the rope enters the pulley and then rubs again as it leaves the pulley groove. Twisting of the rope belt from the horizontal wheel axle to the sloped screw causes extensive rubbing of the rope belt on the sides of the pulleys. The amount of this friction is unknown.
The square pulley would provide traction. Given that the wheel could be operated in either direction, Bessler could demonstrate the water screw load being driven equally well in either wheel direction by crossing the drive rope, or not, as desired. I see no reason to assume it was not a relatively efficient drive means.
CONCLUSION
The vast number of unknown variable factors involved with Bessler's Archimedes screw pump makes any attempt to calculate the power needed to drive it close to worthless because of the vast amount of unknown dimensional factors and the unknown friction factors.
There are unknown variables, but they are hardly "vast".
The simple lifting of a known weight by wrapping of a rope around a known diameter of Bessler's wheel axle tuning at a known RPM speed with speculation that it might have slowed down is a vastly more accurate calculation.
The slowing down of the wheel under the water screw load is not speculation. We know it was measured and specified as a reduction from 26 RPM unloaded to 20 RPM when driving the water screw.
The same goes for the lifting of the hammer weights which involves speculation as to the weight of the wood (different hardwoods have different weights) and speculation as to the actual lift height which must be scaled from the drawings.
The screw length must be derived by measuring the drawing.
It is a scaled drawing and the screw length is 12 feet.
Screw Internal diameter.
The screw internal diameter is unknown because we do not know the screw wall thickness. Thus it is a pure guess. A small change of this variable produces a very large change to the volume of water lifted. See note at end of post.
Hardly a "pure guess", the scale drawing indicates an outside diameter of close to 18 inches. Wall thickness is unknown, but probably quite thin because the inherent geometry of the screw does not require great material strength. An estimate of 1/4 inch wall thickness is probably close.
Screw Core shaft diameter
The screw core diameter can be derived by measuring the drawing.
It is about 2 inches diameter.
Screw Slope.
The screw slope angle must be derived by measuring the drawing.
20 degrees.
Screw Speed.
The screw speed must be derived by measuring the pulley ratios of the drawing.
About 10 RPM.
Screw Vane spacing.
The screw vane spacing is almost totally unknown. The vane spacing (or lead) could be anything. The vane spacing determines how much water will fit inside each 'bucket' that is formed by the vane. We do not know if the vanes were spaced close together or far apart. Spacing makes a big difference in what percentage each bucket is filled.
The scale drawing indicates vane spacing is about 2 feet.
Screw Vane count.
We don't know if it was a single vane pump or a multiple vane pump. It looks like a single vane pump because of the single notches at the ends, but that could be to make the drawing simple. Double lead screw pumps are much more common and are more efficient.
Drawing indicates single vane (it is also the easiest and lightest to construct).
Screw Vane thickness.
The vane wall thickness is totally unknown. If the vane wall was thick then there was less room for the water. If the walls were thin then more water was in the screw.
Once again the basic structure of the screw is quite strong and it would not require the use of heavy materials. I assume 1/4 inch vane thickness would not be far off.
Screw venting.
This aspect needs a little more investigation on my part. I'm concerned about the screw becoming a syphon which would inhibit its operation. A simple solution would be vent holes through the vanes at the core shaft. Such vents would be one of the limiting factors for how full the 'buckets' get filled. Or a screw can 'cup' a certain amount of water and air each rotation, but this method is not shown by Bessler.
Water Immersion level.
The amount of the screw that was above the water level must be measured from the picture. It is obvious that such a level could not be kept constant. If the tank was filled to overflowing when the screw begins to rotate then the water level will drop because water is pumped out of the tank and into the screw before being discharged. To determine how much the water drops you need to know the tank size, which must be scaled from the drawing. Then there is the problem of spillage and leakage which will lower the water level. This is plainly shown in the drawing where spilled water drains through the floor and then outside the building.
Water level does not change pump flow rate (unless it runs dry). As discussed in another thread there is no drain for "spillage and leakage". I have attached a crop of Bessler's drawing which plainly shows the drain is for emptying the water tank.
Friction of the water in the screw.
Churning of water produces friction. The water is churned by each vane as the water is lifted upward through the screw. The water must flow over the surface of each vane as it is lifted. The rough or smooth condition of the vanes would determine the friction. This friction would play a major roles in the overall friction of the screw.
The very low operating speed of the pump would limit churn to a relatively small loss.
Friction of the screw bearings.
The bottom bearing is in the water and cannot be lubricated. The bearings must support pressure in two direction, side ways and end ways. A big factor with bearing friction is always the weight load. Here we have the weight of the screw, which is very big and massive and unknown. Once pumping begins we also have the weight of the lifted water. Bearing friction is constant per rotation. Contrary to what Bill thinks, each rotation produces the same energy loss per rotation regardless of speed. Slower speed does not produce less friction. The bearings would have been a major source of friction. We know nothing about these bearings and thus cannot determine how much friction they produced.
The bottom bearing is very thin and lubricated by the tank water. The top bearing is open and would have been lubricated. Given that the overall construction of the screw was probably very light, due to the inherent strength of the structure, then bearing load (and friction loss) would be relatively minor. I have attached crops of the bearings indicated in Bessler's scale drawing.
Friction of the rope belt.
The screw is shown as being driven by a twisted rope belt on square pulleys. I have no idea why the pulleys were square. Square pulleys make no sense to me. Regardless, all pulleys produce friction. The rope belt rubs on the side flanges as the rope enters the pulley and then rubs again as it leaves the pulley groove. Twisting of the rope belt from the horizontal wheel axle to the sloped screw causes extensive rubbing of the rope belt on the sides of the pulleys. The amount of this friction is unknown.
The square pulley would provide traction. Given that the wheel could be operated in either direction, Bessler could demonstrate the water screw load being driven equally well in either wheel direction by crossing the drive rope, or not, as desired. I see no reason to assume it was not a relatively efficient drive means.
CONCLUSION
The vast number of unknown variable factors involved with Bessler's Archimedes screw pump makes any attempt to calculate the power needed to drive it close to worthless because of the vast amount of unknown dimensional factors and the unknown friction factors.
There are unknown variables, but they are hardly "vast".
The simple lifting of a known weight by wrapping of a rope around a known diameter of Bessler's wheel axle tuning at a known RPM speed with speculation that it might have slowed down is a vastly more accurate calculation.
The slowing down of the wheel under the water screw load is not speculation. We know it was measured and specified as a reduction from 26 RPM unloaded to 20 RPM when driving the water screw.
The same goes for the lifting of the hammer weights which involves speculation as to the weight of the wood (different hardwoods have different weights) and speculation as to the actual lift height which must be scaled from the drawings.
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re: Speculations on the witness's evidence
There is no reason to assume that operation of the stampers did not slow the wheel to some value less than it's free running speed of 26 RPM.eccentrically1 wrote:Regarding how high the stampers were lifted, Bill, wouldn't that be related to the diameter of the axle? And the frequency to the 26 rpm?
I've attached a crop of the stamper and drive mechanism. Bessler's scale drawing indicates a lift height about equal to the axle diameter.
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FunWithGravity2
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- Posts: 1040
- Joined: Thu Jul 24, 2008 10:32 pm
re: Speculations on the witness's evidence
Are we sure that the stampers were driven as depicted, i would think that a pulley with a slack rope would have been the way i would have chosen. As depicted the shock/force of hitting each lifting arm is delivered directly to the wheel.
This is either a conceptualized drawing or says alot about the internal mechanism being able to take jolts to the system. based upon comments about a shove being able to upset the sytem i am curious.
Dave
This is either a conceptualized drawing or says alot about the internal mechanism being able to take jolts to the system. based upon comments about a shove being able to upset the sytem i am curious.
Dave
Si mobile in circumferentia circuli feratur ea celeritate, quam acquirit cadendo ex
altitudine, quae sit quartae parti diameter aequalis ; habebit vim centrifugam suae
gravitati aequalem.
altitudine, quae sit quartae parti diameter aequalis ; habebit vim centrifugam suae
gravitati aequalem.
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nicbordeaux
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- Posts: 2140
- Joined: Wed Sep 30, 2009 2:54 pm
- Location: France
The MT and clue stuff is full of ratchet depictions. There have been many discussions here about how Bessler would have used ratchets. Try using the search option for ratchet.eccentrically1 wrote:That's news to me!However, if the "wheel" was using a ratchet system, as much "evidence" leads us to believe
Wouldn't a ratchet system add unnecessary friction? And what is the evidence for it?
Add friction ? Of course. A ratchet can come with 5 degree "clicks, or once a turn (see the wonderful "Five hundred and-seven mechanical movements" digitalized book (link) posted on this forum by Michael (if not, google it), it contain's anything you will ever need for quicly testing an idea).
So, it adds friction, therefore rduces and slows rotation , swing or vertical travel a mite, but it also allows position of an object to be held for a span. Inasmuch, it can be of great assistance.
I could show you all, but I won't. Not yet, at any rate ;-)
Nick
ps : heading for the bunker.
If you think you have an overunity device, think again, there is no such thing. You might just possibly have an unexpectedly efficient device. In which case you will be abducted by MIB and threatened by aliens.