#### Introduction to Pipe Flow: Screencast

Presents the mechanical energy equation and introduces the concepts of major and minor head loss.

We suggest that after watching this screencast, you list the important points as a way to increase retention.

Shows how to calculate major losses using the Moody chart.

We suggest that after watching this screencast, you list the important points as a way to increase retention.

##### Important Equations:

The Reynolds number, $$Re$$, is used to determine the flow regime.

$Re = \frac{\rho UD}{\mu} = \frac{UD}{\nu}$

where $$U$$ = freestream velocity
$$\rho$$ = fluid density
$$\mu$$ = fluid dynamic viscosity
$$\nu$$ = fluid kinematic viscosity
$$D$$ = pipe diameter

The governing equation for pipe flow:

$\frac{P_1}{\gamma} + \alpha _1 \frac{V^2 _1}{2g} + z_1 + h_P = \frac{P_2}{\gamma} + \alpha _2 \frac{V^2 _2}{2g} +z_2 +h_T + h_L$

$h_L = f\frac{L}{D} \frac{V^2}{2g}$

where $$\gamma$$ = specific weight of the fluid
$$P$$ = pressure at each point in the pipe
$$V$$ = velocity at each point in the pipe
$$g$$ = gravitational constant
$$z$$ = height at each point in the pipe, referenced to the same point at $$z = 0$$
$$\alpha$$ = kinematic energy parameter
$$h_L$$ = head loss
$$f$$ = frictional factor, which can be determined using the Moody chart
$$L$$ = length of the pipe

Although $$h_P$$ is the energy of the pump, and $$h_T$$ is the energy of the turbine, they are usually not included in the basic energy equation, but they must be used when pumps and/or turbines are part of the system.