G D Johnston objects to Bryan Leyland's characterisation of tidal current energy in terms of static head--but this is the basis of

Bernoulli's equation and is conventional (Letters, PE March).

The unsteady

Bernoulli's equation is used for time historical evaluation of the velocity potential and is given as:

The flow from an outlet in the pipe is calculated by applying the

Bernoulli's equation across the outlet.

INVESTIGATION OF THE EFFECTS OF AN EXIT PIPE ON THE CALCULATION OF DRAINAGE TIME OF WATER FROM A TANK USING

BERNOULLI'S EQUATION. VICTORIA Z.

To describe a mathematical model we use momentum equation and extended

Bernoulli's equation:

Bernoulli's equation is the integral of the Euler's equation and applies to general initial and final velocities and pressure.

The initial water velocity is calculated from the water jet pressure using

Bernoulli's equation.

Each section's resistance was then modeled by applying

Bernoulli's equation or Forchheimer-extended Darcy's Law.

Bernoulli's equation tells us that if we have a fluid flowing in a pipe, and a sudden enlargement exists in the pipe, there will be a corresponding drop in pressure.

Flow of the fluid inside the system's pipes and through the output valve, represented by parameters [Q.sub.i] and [Q.sub.o], are described by

Bernoulli's equation: