Why does a centrifugal pump generate axial force?
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Why do centrifugal pumps generate axial force?
When a centrifugal pump is in operation, the pressures on both sides of the impeller are not equal; the pressure at the inlet is lower than that on the back side of the impeller, which results in an axial force that pushes towards the inlet of the impeller. :)
What was said upstairs is correct – it’s the difference in pressure that results in an axial thrust. There is high pressure at the pump outlet and low pressure at the pump inlet, and this pressure difference exerts a thrust on the impeller.
It seems you’re not familiar with fluid handling equipment and don’t know what back pressure is.
Impellers are generally equipped with balance holes to balance the forces acting on them; axial forces do exist, but they are reduced.
All turbine machinery has an axial force from high pressure to low pressure
It is described in detail in the textbook on chemical engineering principles
The pressure difference between the outlet side and the inlet side generates an axial force
The axial thrust is caused by the difference in pressure on the front and rear sides of the pump impeller; there is high pressure at the pump outlet and low pressure at the inlet, and this pressure difference exerts a force on the impeller.
The issue of axial force in centrifugal pumps is frequently discussed on forums; it is mainly caused by the pressure difference on both sides of the impeller. You can also refer to the following content, which will be somewhat helpful to LZ. http://bbs.hcbbs.com/thread-214066-1-1.html http://bbs.hcbbs.com/archiver/tid-176212.html http://bbs.hcbbs.com/archiver/tid-358806.html http://bbs.hcbbs.com/archiver/tid-358806.html
If it is a double-suction pump, then this problem does not exist!
I will explain in detail to the original poster the reasons for the axial force generated by centrifugal pumps: (1) As the fluid flows from the inlet to the outlet of the impeller, its flow direction changes from axial to radial, which results in a reaction force on the impeller. (2) The liquid pressure on both sides of the impeller is asymmetric. Due to the action of axial forces, the impeller can be displaced, altering its concentricity with the overflow channel; this results in a reduction in flow rate and head. In severe cases, friction occurs between the impeller and the pump casing, leading to equipment failure.
There is a pressure difference before and after the pump impeller, which results in an axial force
In turbomachinery such as centrifugal pumps and fans, during operation the pressure at the inlet of the impeller is lower than the pressure on the back side of the impeller at that same inlet; since these pressures are not equal, an axial force is generated. This axial force is reduced by creating balance holes and adding auxiliary impellers, while the remaining axial force is absorbed by the bearings.
The working principle and structural characteristics of centrifugal pumps inevitably result in the generation of axial force
Since the blades are inclined, they actually have a spiral shape; therefore, an axial force is definitely generated during operation. One can draw a diagram and conduct a simple force analysis to understand this
I think a double-suction pump will solve this problem
Generally, in centrifuges with covered impellers and semi-covered impellers, liquid tends to accumulate inside the pump casing, which increases the back pressure on the impeller and exerts an axial force on it. To counteract this pressure, a balance hole is usually provided to equalize the pressure on both sides of the impeller, thereby reducing damage to the impeller and the pump casing
What was said on the 18th floor is correct – centrifugal pumps do not have any issue in dealing with axial thrust
It is caused by the difference in pressure at the inlet side and on the back blade of the impeller