Question about water pressure in IPX6 water intrusion testing of an enlosure

[Gremian]

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In my work I am always having to assess products for how they perform outdoors

One of the tests that we make is Ingress protection IPX6 for water jets
The test is made using a large hose, with water flowing at 100 liters per minute (or 15psi)
The test unit is 3 meters from the nozzle of the hose.

What I would like to know is what is the force acting upon the test product when the water is hitting it?

 

[phinds]

Welcome to the forum. State your question completely and clearly in the appropriate sub-forum and I'm sure someone will help you out.

 

[berkeman]

Probably the Mechanical Engineering forum would be the best fit. It's usually the MEs that do the IPV6 testing in the companies I've worked for.

 

[Gremian]

Hi berkeman. It is the same here.
But what I am looking for is the calculation of force of the water.

If the water is flowing at 15psi and the target is 3 meters from it, what is the force of water on the target at the point where it hits.

I was sure this was more of a physics equation, no?

 

[berkeman]

I was sure this was more of a physics equation, no?

It could be either, but most of our hydrodynamics type questions go in the ME forum. I will move your thread there now.

Your testing is like this, right?

https://keystonecompliance.com/ipx5-ipx6-water-jets/

 

[DaveE]

This will depend greatly on the nozzle size (i.e. stream velocity), stream size at impact, etc.. You can cut steel with the right water jet setup. In any case it is a difficult problem to solve.

 

[DaveE]

Check out the difference between Pelton wheels and paddlewheels. There are issues associated with the surface geometry to take into account. Also consider the difference between force and impulse, impulse is much easier to deal with, IMO.

Again, it's really complicated. Once you've fully specified the problem to get an answer, it may be so specific as to be irrelevant. This is why a lot of engineers end up relying on handbooks and such that have measured "typical" applications which we interpolate/extrapolate (or just guess) from.

 

[berkeman]

If the water is flowing at 15psi and the target is 3 meters from it, what is the force of water on the target at the point where it hits.

Looking at the summary from the link in my post #5, it looks like the test defines the pressure at the target, not back at the nozzle, no?

IPX6 Powerful Water Jet Testing:

Defined as water projected by a nozzle (12.5mm).
The requirement is that the equipment under test (EUT), shall experience no harmful effects from the water being sprayed against the enclosure from any direction.
The test details include a test duration of at least three minutes, water volume of 100 liters per minute and pressure of 100 kN/m² at distance of three meters.

EDIT -- Although, their wording is a bit ambiguous as to whether that water pressure is at the device which is 3m from the hose nozzle, or back at the nozzle 3m away from the device... Do you have access to the full test spec?