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FORCES DUE TO FLOW THROUGH PIPE’S BENDAndersen - Osel Sakadewa

1406604626 - 1406604600Teknik Kimia

A “BUM GUN”

A “Bum Gun” with entrance diameter 27

mm and at exit is 25 mm working at the

pressure from 0.1 MPa ~ 1 MPa. The grip

and the mouth make a 1350 angle bend.

The flow rate is 0.25 kg/s.

Neglecting the friction, determine the

magnitude needed and the direction to

suspend the forces exerted by the water!

STEPS 1 AND 2

• Define the control volume. This contains the fluid in the pipe• between the inlet,1, and the outlet, 2, shown below with the co-ordinate axes.

45𝑜

STEPS 3 AND 4

The forces acting on the fluid in the control volume are:a) Pressure forces are at 1 and at 2. Note that pressure forces always act at right

angles to the cross-sectional area and in to the control volume.b) Structural force, . Since we don’t know either the magnitude or the direction this is

drawn as its two components, and in the x and y directions, respectively.These forces are shown on the CV, as well as the directions of flow at 1 and 2.

45𝑜

STEP 5

From continuity:

STEP 6

Energy :

From Bernoulli’s equation (neglecting friction):

STEP 7

In the x-direction

In the y-direction

Therefore, the force exerted by the pipe on the fluid is:

61.78 °

A plumber is an adventurer who traces leaky pipes to their source.”

- Arthur Baer

Forces through Pipe Bend

Water flows through a reducing bend. Determine the magnitude of the force exerted on the bend in the x-direction. Assume energy losses to be negligible.

Step 1 & 2

1. Draw the sketch from the problem2. Between the fluid flow from A to B, shown with the co-ordinate axes3. Gaya yang bekerja pada fluida pada control volume adalah : a) Gaya tekan pada y

x

Penyelesaian• Continuity

• Energy

• Momentum