Empirical Viscosity Test for Pumps

Sweet solution

http://www.ebay.com/bhp/gallon-honey

Autodesk CFD, ANSYS or any can run a simulation for you, before you and your employer could waste big amount of money and efforts for the test.

Not unless verified by simulation, then rig a test.

I accept fixed contracts this type of job, affordable, I should say.

The calculated value was completed well before my time here, but a customer who bought one unit is asking because the fluid he has may be too thick for our pump. So we want to prove our pumps can handle what the theoretical limit claimed.

Drew K

Ok, so it's more like an exhibit or a demo, so go ahead.

Can you send your customers a trial pump, a barrel, and a stopwatch--and let them provide the fluid?

Who made your pumps? They must have all the data you need. If their pumps did not do what they claimed, they would soon be sued out of existence.

I would first consider renting or purchasing a calibrated viscometer so you can first verify the test fluid has the desired viscosity. Then I would obtain a few organic fluids in the range your pumps should operate. Unless your pump is a "food grade" pump, don't eat the test fluid. However, it will be easier to clean your pump out afterwards if you use some syrup. You probably can also adjust the viscosity by thinning or thickening.

The only way to prove the pump will perform with the customer's fluid is to pump the customer's fluid.

Anything else is an estimation, and invalid.

Yes, that will prove if the pump will perform with a customer's fluid. That is not the question. The question is how to demonstrate pumping 10,000 CPs fluid to prove the manufacturer's claim. The customer can be wrong about the viscosity of their fluid. The manufacturer can also be wrong in their claim.

Whatever. I doubt the manufacturer is wrong about their claim.

And, that won't matter anyway if the pump won't pump the customer's fluid.

The best way, and the most accurate way is to use a suitably sized sample of the fluid originally used to test them. When substituting with "test fluids" other variables are potentially introduced. Some materials are thixotropic and the viscosity decreases with agitation/pumping, spackling compound is one example of this. Some fluids will increase in temperature as they are pumped and the viscosity lowers.

Get a sample of the material that the pump was originally tested with to make the claim of performing with 10,000cps and test with that. Also, make sure you use the same viscometer model that was originally used if possible. To be even safer make sure the same type of disc or sensing element is used. Some types are difficult to reproduce the same numbers with different units of the same model such as Brookfields.

Good Luck, Old Salt

There will always be doubters of the tests if a calibration liquid is substituted for the original liquid pumped. "It ain't like the real thing baby" to quote a song popular in my much younger years. There are too many possibilities for the test not to be accurate with anything but the original 10,000 cps fluid that was originally used.

Unfortunately, the person questioning the results will probably be the president, vice-president, your boss or a bean-counter who knows nothing about what is going on. They will always bring the subject up because they don't understand what is going on.

Good Luck, Old Salt

Depending on the volumes pumped, calibration fluid could get awfully expensive.

Better to create your own with a food thickening agent such as sodium carboxymethylcellulose at slightly above your test temperature.

Of course, you will need to sample and test with a viscometer.

A wealth of great comments. I will check to see if it is cheaper to get a viscometer or by the calibrated fluid.

Nobody here knows if there was an empirical study done at the time the theoretical value was calculated so we want to do one now...some of the current benevolent overlords agree it is good to back up your words with proof!

Drew K

Now, I'm confused, again.

Did you buy the pump, or build the pump?

I once worked at an OEM where we did both.

All in-house pump designs were subjected to a full battery of tests, on a pump stand, prior to release to production for use in equipment. I made sure they met specification. The buck stopped at my desk.

Commercial pumps were tested by us prior to release into production.

We rarely could exactly duplicate the suppliers numbers.

<...can...> What does that mean?