Correct Answer - Option 2 : friction
Explanation:
Losses in pipe: 2 type
Major loss: Major loss occurs only due to friction.
Minor loss: Depend on different factors.
Major loss:
Major loss in the pipe due to friction is given by the Darcy-Weisbach equation.
\({h_f} = \frac{{fL{V^2}}}{{2gD}}\)
Here, L = length of pipe
D = dia of pipe
V = mean velocity
f = friction factor (0.02 to 0.04 for metals)
hf = head loss due to friction
Minor loss:
Different type of minor losses in pipe
| Losses due to the sudden expansion |
\({h_{le}} = \frac{{{{({V_{^1}} - {V_{^2}})}^2}}}{{2g}} = \frac{{{V_1}}}{{2g}}{(1 - \frac{{{A_1}}}{{{A_2}}})^2}\)
|
| Losses due to a sudden contraction |
\({h_l} = \frac{{{{({V_c} - {V_2})}^2}}}{{2g}} = \frac{{{V_2}^2}}{{2g}}{(\frac{1}{{{C_c}}} - 1)^2}\)
If Cc is not given then, \({h_l} = \frac{{0.5{V_2}^2}}{{2g}}\)
|
| Losses at the exit of the pipe |
\({h_l} = \frac{{{V^2}}}{{2g}}\) |
| Losses at the entrance to the pipe |
\({h_l} = \frac{{0.5{V^2}}}{{2g}}\) |
| Losses due to bends |
\({h_l} = \frac{{K{V^2}}}{{2g}}\)
K = 1.2 for 90◦
K= 0.4 for 45◦
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