The backflow of the magnetic pump increases and the power output decreases – what’s the problem?
Thread Content
We have two sets of magnetic pumps here; as the flow rate increases, the power decreases. It seems like it no longer meets the pump’s characteristic curve. Logically, as the flow rate increases, more work needs to be done, so the power should be higher～～～～ This applies to systems with two impellers as well
How can one tell that the power has decreased?
Why increase the return flow rate? Is it because the normal flow rate of the pump is too low, which makes cavitation more likely to occur?
It’s better to check the pump’s performance curve; generally, as the flow rate increases, the outlet head decreases
When you increase the backflow, it seems like more work is required, but the distance over which that work is done is shorter, and thus the resistance at the outlet is reduced. Doesn’t that mean the power output will be lower? It should increase, that’s how I understand it. When the backflow is increased, the pressure in the outlet pipe should decrease – is that correct?
This is quite simple; based on the formula for shaft power, it’s easy to conclude that 1) density decreases as temperature rises, 2) flow rate increases while head pressure decreases, and 3) the pump efficiency reaches its optimum. These are the main reasons
Did you not understand what I described? The other pumps don’t have this problem; it’s only these two pumps. They feature low flow rates but high head pressure: 2.14 cubic meters per hour and 18 meters. The medium used is HF
The characteristic curve of the pump requires that there be no backflow! As the backflow increases, the actual work done decreases~