Impingement/Physics Question

[Red Baron]

My D&S i5000s' side-spinners are spun by slightly twistign each nozzle to opposite angles. The greater the angle, the faster the spinner spins. I don't know if the faster spinning spinners clean any better but I'm sure the customers' perception is that it's working harder. My question is, is it an equal and opposite force kind of thing where the spray that is hitting the surface in a faster side motion with the faster spinners, is offset because there is a little less stright on to the surface/car spray?

 

[rph9168]

The role of a detergent is to lift the soils from the vehicle's surface while impingement pushes that released soil away. To prove the point put a piece of paper on a flat surface and blow directly down at it. It will not move. Now move off to the side and blow at it at an angle. The paper will pull away from the surface. While blasting at the surface may look like it is doing the job, using impingement or angling the spray is much more effective in cleaning. While the speed of the spinners add to the sizzle, the angle of the spray is really doing the work.

 

[Bubbles Galore]

^yep, that's it

 

[ProCarWashes]

?

I guess you can pat yourself on your back for figuring this action of the SPINNING arms the best action since sliced bread. Did you happen to notice that the nozzle tips are traveling away from the surface they are pointed at? Which lessens the impact or force the water would have if it had hit the surface more directly. Your example of blowing down on paper is laughable. What about this example: A sandblaster pointed at a surface at an angle has Less penetrating power than pointed directly at the surface. The paper has nowhere to go lying on a table flat. But can move to the side. Your example proves nothing.

 

[rph9168]

The sandblaster works due to sheer force and depends on the media used. The paper demonstration is a good illustration of impingement. It does not depend on anything other than the force of the spray. The force of water hitting directly on the surface will remove the soils directly in its path but impingement "peels" those solids off with much less pressure. My suggestion was only to demonstrate the effect of impingement. If you want to sandblast soils off the finish feel free to do so.

 

[Red Baron]

I guess you can pat yourself on your back for figuring this action of the SPINNING arms the best action since sliced bread. Did you happen to notice that the nozzle tips are traveling away from the surface they are pointed at? Which lessens the impact or force the water would have if it had hit the surface more directly. Your example of blowing down on paper is laughable. What about this example: A sandblaster pointed at a surface at an angle has Less penetrating power than pointed directly at the surface. The paper has nowhere to go lying on a table flat. But can move to the side. Your example proves nothing.

The angle of the tips is barely noticeable - I'd guess it's not much more than happens by eyeballing the tip angle on the spinners on the standard 5000. Not a factor, imo, when that could probably be offset with another 25 psi (just grabbing out of thin air, admitedly).