Losses

Energy loss in fluid motion is directly proportional to $v^2$ where $v$ is the velocity.

Types

Local loss

Occurs when there is a sudden change in flow.

$$K_L \frac{v^2}{2g}$$

Here:

• $K_L$ - local loss coefficient
• $v$ - velocity
• $g$ - gravitational acceleration

Friction loss

Occurs because of

• viscosity
• friction between fluid and pipe wall

When the fluid is under turbulent flow:

$$\lambda \frac{L}{D} \frac{v^2}{2g}$$

Here:

• $\lambda$ - friction factor
• $L$ - length of the pipe
• $D$ - diameter of the pipe
• $v$ - velocity
• $g$ - gravitational acceleration