Whether the pumps flow more in series or parallel depends on the system curve. Given that your series configuration had straight through plumbing and no elbows, the system curve was quite different from your parallel configuration had had the elbows which cause significant flow resistance. Had you plumbed the parallel pumps using two “Y” fittings rather than the 90 elbows, I suspect you would have seen much closer results. And since parallel pumps are about increasing flow rather than pressure, you should have used pipes into and out of the “Y” fittings that had a cross sectional area about twice as big as the pump diameter. Since you kept the same size tubing and added in the elbows, you were keeping the system curve steep with high pressure requirement as the flow increases. Two pumps in series will work better with a steep system curve as you need pressure to get flow. If you made the system curve shallower by using larger inlet and outlet pipes and smoother flowing Y fittings to separate and combine the flow from the parallel pumps, you would have seen higher volume from the parallel configuration. So, which is better depends on the system. It appears you desire to use these pumps in a high resistance system and in that case the series configuration will be better.
Hey LTVoyager! 👋 I build equipment for exterior softwashing and I'm interested in getting the best flow-rate and pressure out of my systems. I use 12v everflow pumps, usually 5.5gpm sungle pumps. I have recently installed a 7gpm pump and it's not as great of an improvement as I was hoping for. Now, I'm thinking about running dual 12v 7gpm pumps and I want to be able to get the best distance, for applying my solution to roofs, etc... I'm always looking to improve and I came across your comment, which had me thinking about orher factors of fluid dynamics and how I can get the best results, for what I'm trying to achieve.
@@curtislitsair1093 The increase in the system curve is nonlinear so adding twice as many pumps doesn’t get you twice as much pressure or volume as you are simply moving up an ever steeper system curve. This is a longer video, but the professor covers this pretty well. Basically, if you have a high head, low volume system, then pumps in series is generally better. If you have a low head, high volume system, then pumps in parallel are better. ruclips.net/video/iDRoSxZKKz8/видео.html
@@LTVoyager This and the linked video basically shows that the amount of changes you would have to make to an existing system to get an increase from parallel is far outweighed by the cost. Essentially if you have two identical pumps you will always put in series because the system losses even with this guys test show literally two 90 degree bends and some extra hose is "too restrictive" to match theory. In real life you don't change potentially hundreds of feet of delivery system. You just buy a bigger pump or put two in series. Do you agree?
Should of had the outlet double the size of the feed considering its trying to push twice the amount of volume I guarentee better results in flow in parallel
This isn't true right? That's all just theory and in real life (the video) basically any restriction causes so much head pressure that parallel does not equal double the flow rate. This video reached the same conclusion, the theoretical graphs are misleading because they make up a system pressure curve that's artificially flat
@@baldrickscunningplan6154 sorry all the diagrams of two theoretical identical pumps say it doubles the flow. They draw all the points off two the right of the graph at 2 times current Q. In this test and in the professors video it didn't get anywhere close to double the flow and actually got less than two pumps in series
@@chrisb4825 No one said there was double the amount of flow. You are making that up in your own head. There is an increase in flow when situated in parallel as opposed to series. That was clearly demonstrated in this video. If you don't believe your own eyes. We cannot help you.
@@baldrickscunningplan6154 did you even watch the video? At 11:49s he summarizes that the series configuration flowed more than the parallel configuration. 21.5lpm vs 19lpm...
Interesting. I was expecting less difference between serial and parallel, but slightly more from the series config, like 50% more than a single pump. I'm really waiting for the bigger pump video. ;)
Very possible to "overcool" an engine, like when a thermostat is stuck open. Water circulates too fast and it doesn't have time to absorb heat energy, and engine cylinders run dangerously hotter. ....and the heater core doesn't blow hot and temperature sensor reads very low.
Yes, but speed of the El water pump can be controlled by a speed controller, it can be turned down, but can not be turned up over its maximum speed, so having too big of a pump is better than not having enough pump.
Can you elaborate on his flaws? Unless the measured flow rate is inaccurate then I would say it was valuable data with that particular hose routing setup/diameter
Whether the pumps flow more in series or parallel depends on the system curve. Given that your series configuration had straight through plumbing and no elbows, the system curve was quite different from your parallel configuration had had the elbows which cause significant flow resistance. Had you plumbed the parallel pumps using two “Y” fittings rather than the 90 elbows, I suspect you would have seen much closer results. And since parallel pumps are about increasing flow rather than pressure, you should have used pipes into and out of the “Y” fittings that had a cross sectional area about twice as big as the pump diameter. Since you kept the same size tubing and added in the elbows, you were keeping the system curve steep with high pressure requirement as the flow increases. Two pumps in series will work better with a steep system curve as you need pressure to get flow. If you made the system curve shallower by using larger inlet and outlet pipes and smoother flowing Y fittings to separate and combine the flow from the parallel pumps, you would have seen higher volume from the parallel configuration.
So, which is better depends on the system. It appears you desire to use these pumps in a high resistance system and in that case the series configuration will be better.
Hey LTVoyager! 👋
I build equipment for exterior softwashing and I'm interested in getting the best flow-rate and pressure out of my systems. I use 12v everflow pumps, usually 5.5gpm sungle pumps. I have recently installed a 7gpm pump and it's not as great of an improvement as I was hoping for. Now, I'm thinking about running dual 12v 7gpm pumps and I want to be able to get the best distance, for applying my solution to roofs, etc... I'm always looking to improve and I came across your comment, which had me thinking about orher factors of fluid dynamics and how I can get the best results, for what I'm trying to achieve.
@@curtislitsair1093 The increase in the system curve is nonlinear so adding twice as many pumps doesn’t get you twice as much pressure or volume as you are simply moving up an ever steeper system curve. This is a longer video, but the professor covers this pretty well. Basically, if you have a high head, low volume system, then pumps in series is generally better. If you have a low head, high volume system, then pumps in parallel are better. ruclips.net/video/iDRoSxZKKz8/видео.html
Wow, you just taught me something. Thank you ( :
I got out of that that pressure and flow are 2 different animals🔥
@@Chris-ji8jw Yes, related, but different.
@@LTVoyager This and the linked video basically shows that the amount of changes you would have to make to an existing system to get an increase from parallel is far outweighed by the cost. Essentially if you have two identical pumps you will always put in series because the system losses even with this guys test show literally two 90 degree bends and some extra hose is "too restrictive" to match theory. In real life you don't change potentially hundreds of feet of delivery system. You just buy a bigger pump or put two in series. Do you agree?
I was hoping he would plumb the pumps in parallel with 2 intakes(separate intake for each pump) and both pumps Y'ed into a single outlet.
Try with 2 inlets instead of one
2 inlets would definitely increased flow close to 100%...the single inlet restrict the flow...
You should leave 2 outlets free instead of combining, this may increase flow rate.
Should of had the outlet double the size of the feed considering its trying to push twice the amount of volume I guarentee better results in flow in parallel
That would defeat the whole point of the test.
I think that parallel is going to flow more fluid. I mean, not connected together.
Series =more pressure.
Parallel = more flow.
This isn't true right? That's all just theory and in real life (the video) basically any restriction causes so much head pressure that parallel does not equal double the flow rate. This video reached the same conclusion, the theoretical graphs are misleading because they make up a system pressure curve that's artificially flat
@@chrisb4825 Where did I say that parallel equals "double" the flow rate?
@@baldrickscunningplan6154 sorry all the diagrams of two theoretical identical pumps say it doubles the flow. They draw all the points off two the right of the graph at 2 times current Q. In this test and in the professors video it didn't get anywhere close to double the flow and actually got less than two pumps in series
@@chrisb4825 No one said there was double the amount of flow. You are making that up in your own head. There is an increase in flow when situated in parallel as opposed to series. That was clearly demonstrated in this video. If you don't believe your own eyes. We cannot help you.
@@baldrickscunningplan6154 did you even watch the video? At 11:49s he summarizes that the series configuration flowed more than the parallel configuration. 21.5lpm vs 19lpm...
Interesting. I was expecting less difference between serial and parallel, but slightly more from the series config, like 50% more than a single pump.
I'm really waiting for the bigger pump video. ;)
I was expecting more too, but it didn't happen.
In series pump don't create more flow just more suction right? In parallel it should be same suction but more flow.
Are you doing this for your motorcycle. Also remember the faster you move fluid u also have to cool it
I did the test to find out what pumps would do connected in series or parallel, and now I know.
Horsepower vs torgue
Very possible to "overcool" an engine, like when a thermostat is stuck open. Water circulates too fast and it doesn't have time to absorb heat energy, and engine cylinders run dangerously hotter. ....and the heater core doesn't blow hot and temperature sensor reads very low.
Yes, but speed of the El water pump can be controlled by a speed controller, it can be turned down, but can not be turned up over its maximum speed, so having too big of a pump is better than not having enough pump.
I appreciate your tests, but your tests are severaly flawed.
Can you elaborate on his flaws? Unless the measured flow rate is inaccurate then I would say it was valuable data with that particular hose routing setup/diameter
The Ts were the problem