Torques in a Pump: Understand Opposite Signs

  • Thread starter Thread starter Mikealvarado100
  • Start date Start date
  • Tags Tags
    Pump Torques
AI Thread Summary
In a pump operating at steady state, the pump torque is positive while the fluid torque is equal in magnitude but negative in direction, resulting in a net torque of zero. This occurs because torque represents a force that induces rotational motion, and the forces exerted by the pump and the fluid are equal but act in opposite directions. The positive sign of the pump torque indicates its direction of rotation, while the negative sign of the fluid torque reflects the opposing force exerted by the fluid. Understanding this relationship clarifies why both torques, despite rotating in the same direction, are assigned opposite signs. The interaction between the pump and fluid is essential for maintaining equilibrium in pump operation.
Mikealvarado100
Messages
52
Reaction score
0
Hi
In a pump (which operates in normal condition: steady state), pump torque is positive and fluid torque is of equal magnitude and of opposite direction so that the sum of both is zero. ''P. 66 of 'Water Hammer: An Analysis of Plumbing Systems, Intrusion, and Pump Operation' by: Dr. Loganathan and ...
I need so explanation about opposite sign of pump torque and fluid torque? Both rotate in a same direction, then why one of positive and the other is negative?
 
Physics news on Phys.org
Remember that torque isn't itself a rotation, it is a force. Specifically a force that tends to cause rotational motion. See here: https://en.wikipedia.org/wiki/Torque

The force from the water on the pump is equal to the force from the pump on the water, but in the opposite direction. Because it is in the opposite direction, the direction of torque is also opposite, hence the negative sign.
 

Thread '1:1 versus 2:1 Mechanical Advantage debate'

The rope is tied into the person (the load of 200 pounds) and the rope goes up from the person to a fixed pulley and back down to his hands. He hauls the rope to suspend himself in the air. What is the mechanical advantage of the system? The person will indeed only have to lift half of his body weight (roughly 100 pounds) because he now lessened the load by that same amount. This APPEARS to be a 2:1 because he can hold himself with half the force, but my question is: is that mechanical...
View full post »

Thread 'Average velocity as a weighted mean'

Hello everyone, Consider the problem in which a car is told to travel at 30 km/h for L kilometers and then at 60 km/h for another L kilometers. Next, you are asked to determine the average speed. My question is: although we know that the average speed in this case is the harmonic mean of the two speeds, is it also possible to state that the average speed over this 2L-kilometer stretch can be obtained as a weighted average of the two speeds? Best regards, DaTario
View full post »

Thread 'Newton's first law?'

Some physics textbook writer told me that Newton's first law applies only on bodies that feel no interactions at all. He said that if a body is on rest or moves in constant velocity, there is no external force acting on it. But I have heard another form of the law that says the net force acting on a body must be zero. This means there is interactions involved after all. So which one is correct?
View full post »

Similar threads

A Modeling the damping of a physical rigid pendulum
Replies
1
Views
2K
Underground pump vault airflow considerations
Replies
15
Views
3K
In which direction a spherical particle moves under torque?
Replies
6
Views
2K
Understanding Torque and Reference Frames in Rotational Motion
Replies
4
Views
2K
Torque on a Pivot Point With Multiple Forces and Different Directions
Replies
6
Views
2K
What is the definition and significance of torque in physics?
Replies
1
Views
4K
Calculating Force & Torque from Submersible Well Pump
Replies
1
Views
2K
B Sign conventions in torque and non-uniform circular motion
Replies
1
Views
1K
Force on a rotating wheel/disc
Replies
25
Views
2K
Pump has a suction lift of more than 10.3 m
Replies
6
Views
6K

Hot Threads

Recent Insights

Back
Top