What is the Force Exerted on Supports Holding a 90 Degree Reducing Bend Pipe?

In summary: The expression for the loss coefficient is: Loss Coefficient = (Velocity Heads Lost * Density of Fluid) / (Flow Rate * Diameter of Entrance) In this case, the loss coefficient is 0.75, because 500 gpm of water will lose 75 velocity heads over its travel through the bend.
  • #1
gfd43tg
Gold Member
950
50

Homework Statement


A 90 degree reducing bend has an inlet diameter of 4 in. and an outlet diameter of 2 in. If water enters the bend at a pressure of 40 psig and a flow of 500 gpm, calculate the force (net magnitude and direction) exerted on the supports that hold the bend in lace. The loss coefficient (number of velocity heads lost due to fluid frictional drag) is 0.75 based on the highest velocity in the bend.


Homework Equations





The Attempt at a Solution



For this problem, I am having troubles finding the pressure at the outlet, as well as the force of gravity in my first momentum balance in the y-direction since I don't know the volume of the pipe. Also, I'm not sure which direction the drag force should go, I've seen it in the lecture notes as being positive in a situation where water was flowing up a pipe, which seems odd to me, I imagine it would oppose motion similar to friction.
 

Attachments

  • 2.1 attempt 1.pdf
    315.7 KB · Views: 367
Physics news on Phys.org
  • #2
... Deleted, because I posted to the wrong thread.
 
  • #3
This problem doesn't give me the pressure at the outlet, and it doesn't specify that it is open to the atmosphere, so I am not sure what to use.

I also do not understand the jargon ''velocity heads''. What does it mean with reference to the expression for the loss coefficient?
 
  • #4
To calculate the force, I believe you only need are the flow rate (500gpm), the diameters of the entrance (4 inches) and exit (2 inches), and the fluid density (water).
 
  • #5
Well that is the information given, but for my momentum balance I don't know how to account for the gravitational force in the y-direction without some information about the size of the tube, meaning I don't know the mass of the water.
 
  • #6
You also don't know which end is up.
If you want to handle gravity, just prepend your answer with "Aside from supporting the weight of the plumbing and water, ...".
 

1. What is the force on a reducing bend pipe?

The force on a reducing bend pipe refers to the amount of pressure or stress that is applied to the pipe due to the movement of fluid or gas through it. This force is typically measured in units of pounds per square inch (psi) or newtons (N).

2. How does the force on a reducing bend pipe affect its structural integrity?

The force on a reducing bend pipe can cause bending, buckling, or other forms of deformation in the pipe. This can potentially weaken or damage the pipe, leading to leaks or even failure. It is important to consider the force on a pipe when designing and installing it to ensure its structural integrity.

3. What factors affect the force on a reducing bend pipe?

The force on a reducing bend pipe can be affected by several factors, including the type of fluid or gas flowing through the pipe, the velocity of the flow, the angle of the bend, the diameter of the pipe, and the material and thickness of the pipe. Other external factors, such as temperature and external pressure, can also play a role.

4. How can the force on a reducing bend pipe be calculated?

The force on a reducing bend pipe can be calculated using mathematical equations that take into account the factors mentioned above. These equations may vary depending on the specific situation and the type of pipe being used. Consulting with a qualified engineer or using specialized software can help accurately calculate the force on a pipe.

5. How can the force on a reducing bend pipe be reduced?

The force on a reducing bend pipe can be reduced by using appropriate support structures, such as brackets or clamps, to distribute the force evenly along the pipe. The pipe can also be reinforced with thicker or stronger materials, or by using multiple bends instead of a single sharp bend. Proper maintenance and regular inspections can also help identify and address any potential issues before they become a problem.

Similar threads

  • Mechanical Engineering
Replies
20
Views
7K
  • Engineering and Comp Sci Homework Help
Replies
1
Views
1K
  • Engineering and Comp Sci Homework Help
Replies
1
Views
2K
  • Classical Physics
Replies
28
Views
2K
  • General Engineering
Replies
11
Views
2K
  • Engineering and Comp Sci Homework Help
Replies
2
Views
4K
  • Engineering and Comp Sci Homework Help
Replies
11
Views
2K
  • Mechanical Engineering
Replies
31
Views
2K
  • Engineering and Comp Sci Homework Help
Replies
7
Views
1K
  • Engineering and Comp Sci Homework Help
Replies
5
Views
1K
Back
Top