To determine minor losses due to line and branch flow at 90° Tee.

Object

To determine minor losses due to Line and branch flow at 90° Tee.

Apparatus

fluid friction apparatus; hydraulic bench; and stopwatch.

Fig. Fluid friction apparatus

Theory

(A)Line Flow(B) Branched Flow

The value of the loss coefficient for line flow in the case of 90^o Tee joint, KT90, is equal to 0.2.

The value of the loss coefficient for branched flow in the case of 90^o Tee joint, KT90, is equal to 1.0.

For the sake of verification of the value of the loss coefficient due to the 90^o Tee joint, we use the relationship

where

l

h  K

2

1

V

T 90 2g

(1)

hl = loss of head due to 90^o Tee joint

V1 = velocity of flow at section-1 = Q/A1 where,Area of flow at section-1 =

A  2

1

d

41

 3.14

4

(1.7)2

 2.27

cm2

(since d1 = 17 mm = 1.7 cm)

Putting values in Eq.(1),

Procedure

KT 90

2g

2 .hl

V



1

2  981

(Q / 2.27)2

.hl

 10108.2 hl

Q2

(2)

1. Fill the tank of the hydraulic bench with clean water.
   
2. Connect the fluid friction apparatus with the hydraulic bench.
   
3. Open the valve(s) that allow flow to the section under consideration and close all the irrelevant valves of the pipe friction apparatus.
   
4. Connect the two ends of the tubes to the pressure-tapping nipples at either side of the pair of elbows and manometer.
   
5. Slightly open the flow control valve on the hydraulics bench.
   
6. Remove air bubbles from the tubes by opening the vent valve and drain valves of the differential manometer.
   
7. Read the heads in the monometers corresponding to the pressure along the entry and exit of the sections under consideration.
   
8. Collect water in the volumetric measuring section of the hydraulic bench. Read the volume collected as well as the time taken to collect that volume of water.
   
9. Open the flow control valve at the hydraulic bench slightly more to take new readings.
   
10. Repeat steps 7 and 8 to observe new readings.
    
11. Carry out computations as per the table below and compare the average value of Ke and Kc with those given in the literature as discussed above.

Observations and Calculations

Comments