Big Props to Pump Design Engineers

Started my Sunday, pretty typical, hanging with the kids etc. Thunderstorms had kicked in and we had one of the hardest rains in Philly in a very long time. Having a fairly old house by US standards comes with flooding wet basements from time to time. As you can imagine the clean up side of the story was less than fun.

I purchased a submersible pump (Water Ace Model R6S) model from Lowe's or Home Depot a few years ago for just such an occasion. Fortunately, I have only needed to use it only a few times and it has saved me a ton of aggravation. It is amazing the volume of water that can accumulate in a very short time. I bet I pumped a few 100 gallons in less than an hour. It got me thinking of all the pump engineers I have spoken to over the years and it was really cool to use a device where some engineer somewhere in the world designed it so that it just worked. Maybe, just maybe CFdesign (or some CFD software) played a contributing factor on the design.

Check out the pump above in action. Got me also thinking, about my expectations as a consumer of what appears to be a simple device. I want to just stick it in the watery/muddy mess and turn it on and miraculously it just works. Fact is, that is basically what has happened, every time I used it. But in reality, what appears to be a simple device is pretty sophisticated. It has moving parts internally, tight clearances and is expected to prime itself and pump "whatever". Obviously the rain water gets mixed with the sand and dirt from my cellar floor as well as all kinds of debris it picks up along the way. There is a very simple screen on the suction side that allows the debris to collect in a pile instead of being suctioned into the impeller etc. But, watching the discharge end its pretty obvious that this "simple" pump is working it and pumping all kinds of stuff.

Not trivial stuff to design, obviously. We have worked with the folks at Pentair Pumps (parent company of Water Ace folks) for a few years as well as many other pump manufactures.

Take, Cornell Pumps shown above for example, we have helped them reduce the amount of prototyping. There is a long list of things Upfront CFD can do to help such as providing flow rate, pressure head, performance curve data, efficiencies and torque to name a few of the basics. But where we really help is seeing inside the device, which simply can't be seen in a testing environment.

At the end of the day, the cleanup was no fun at all. But it always brings a smile to see products designed by mechanical engineers that just work as expected, easy to forget the blood, sweat and tears that was put into the design.

When Everyday Life & CFD Converge

My wife convinced me to put a pool in our backyard. Probably not what you are thinking. You immediately thought in-ground, diving board with a slide and grotto, right? Not even close. We purchased an Easy Set Pool. You know the kind with the blow up ring at the top and you just fill it with water. Well, 3 pool fills later on uneven ground, the pool is up and running. "Easy" is all relative.

It comes with its own pumping filtration system. Enter the CFD part of the story. I turned it on initially and was amazed how quiet it was and the pumping power was amazing. Over the course of a couple weeks, I noticed that the pump was not cleaning the pool. I then noticed that there were large pockets of air at the discharge of the pump. I vented the pump numerous times and it seemed to be ok, but eventually would lose suction. Really cool to see cavitation in action and the effect it has on the performance of the pump.

Not one to read directions, I figured it was time. Sure enough, it recommended changing the filter on the pump every few weeks. I quickly changed out the filter and was having a great time checking out the internals of the pump, impeller, filter etc.. The filter was packed with all kinds of stuff, clearly impeding the performance of the pump. I have seen literally 100s of pump CAD models and run countless CFD analyses on pumps but haven't seen the inside of too many in person. I quickly re-assembled and the pump worked like a charm. It made me appreciate even more the challenges that manufactures have to go through everyday to ensure their products perform as expected. Competition is tough everywhere and you have to get it right the first time.

Above is a model we did for Davey Water Pumps awhile back. Click on the image for more details as well. They were able to improve efficiency by 15% by redesigning the pump in CAD and leveraging the CFD results to drive the design changes. As consumers, we just expect that the pump will work all the time. Pump manufactures surely have a difficult challenge to package the pump in a small area, make it as efficient as possible, quiet as possible and sell for less than $100. There has to be a streamlined way for designers to gain insight to their designs.