For those interested but may not have found before, the below site provides a continuously updated animated map of wind pattern throughout the continental US
PS I have a serious allergic reaction to a species of tree that grows NW of my location and during their pollination period I use this...
@windy miller, You are the OP so it would seem that you are the one to determine the criteria; although, I admit that is a difficult task; and, is why I posted my inquiry after pondering the issue for a while. Based upon your above criteria, it probably depends very much upon the configuration...
Using std 8" sch 40 PVC pipe dimensions; and, PVC material physical data from the below reference, I calculate about 0.65 Gal / 10 psi will be expelled due to pipe diametrical and longitudinal contraction while reducing the test pressure from 150 to 0 psig with an initial 1300 gallon pipe filled...
Do you have a pass/fail leak criteria for your pipe system; and, if so, who is determining this criteria i.e. is it your's internally or is it a customer's specification.
@Baluncore
Thankfully, my issue is now fully resolved and we still have full correlation.
My late night investigation just revealed that: Atan(L1/(D2*PI) = 33.995°, so using D2*PI() is the correct interpretation for my analysis.
Sometimes the hardest part of getting an answer to an issue is...
@Baluncore , After all of our work I hardly believe I am posting this.
Last night, I began to consider that I had made an error in my above calculation by using D2*π as the distance the ball traveled for each wrap of the helix in my in my F = E/n/(D2*π) calculation; when, I should have used:
F...
@vxiaoyu18 , Hello, from Houston, Texas, USA, the temperature is 23° C and it is raining.
I am happy we managed to find a solution for your issue and learn a bit for ourselves as well. This is what worldwide collaboration can achieve in solving problems . It is a shame that some of our...
@Baluncore , I had no doubt that your solution is correct; but, if my actually would match it results. At the same time, it is nice to have a correspondence of two methods.
This morning I fell into the mode of: Well, if my other method wasn't going to work then it was time to grab sometime off...
I think in all such cases the issue comes down to personal integrity and the definition of that can vary considerably from one society and one individual to another. For engineers, I believe they must always be consider the consequences of their choices of professional activities; but, that is...
@Baluncore I now believe you are correct, another quick review of my method now convinces that there is no simple geometric calculation solution to this issue; and, beyond that all I can say is that to me, what you have done is amazing work.
@Baluncore I am glad to see your calculation. Well done.
Now, it is time for me to see if I can develop a realistic version of mine for comparison. Obviously my final q equation should be in line with your's.
The issue was that when the helix axis becomes horizontal α = 0°, that is the point at which there will be no torque on the helix due to the ball wt. and my current program does not do that. I am now going to work to correct that issue.
That is correct.
Above you state that the ball "radius" is .045m but the:
helix tubing inside diameter = .5*(D3 - D2) - 2*s = .5*(.226 - .118) - 2*.004 = .046m
So is the above a typo and ball "diameter" = .045m
The torque you calculate from your I equation is the torque required to accelerate (or decelerate ) the rotational speed of the pipe from one rpm speed to another rpm speed; but, must also include any external rotational resistances, such as the pipe's supporting roller's contact and bearing...
@Baluncore, Good catch, I understand your point and you are correct. While first developing my calculation, whenever α rotated below α (34°) I was getting negative tangent force values, so I worked out a method to correct that issue.
However, while now looking at a diagram I drew today, it...
Well I have a new analysis (much better than my last effort) that seems to work but does not correlate with the Bernoulli or a modification of that equation as discussed above.
The sin(α + β) equation simply converts angle inputs in terms of "β" to be converted into an equivalent rotation of "α"...
Other than a force from an impact force being resisted by the inertia of a body you can not create a force on an object without a simultaneous force from the opposite end.
From here I am going to leave to the other forum members to address this with you.
With only one other viewer than my...
"the fact that forces propagate at the speed of sound in solid materials"
A contact shock wave will propagate through a rod at the speed of sound of the material; but, I am not sure that is true for an applied force which is applied at both ends of the object and will simultaneously and...
I fully agree.
On the issue of the cancellation of the radius, I observed that in the Bernoulli formula discussion but was unable to really comprehend it; so, I need to go back and take another look at that issue.
Good work, I also see that you revised the helix pitch angle to = asin(L1/.44 (one wrap of the helix coil)) = 33.99°, which seems to make makes sense to me as well.
I have calculated the torque based upon the Bernoulli's method and there is a problem for your application and there is an issue for it relative to your application because as α approaches 90° its calculated torques for your ball M*g increase unrealistically, i.e. for α = 80° its calculated...
No problem It was strictly a terminology issue.
Below is a formula I have developed based upon my last best theory (i.e. the pitch angle and tangent force determined with the helix axis vertical and then modified by the the helix angle; and, the ball contact radius being from the helix axis to...
I am working on an equation for the torque and noticed that the above dimensions in your Post#31 do not appear to be correct because they indicate that the helix tube length is shorter than the helix length. What am I misreading?
Edit: I used the calculation to determine the tubing length and...