Page 27 - BASIC CONCEPTUAL OF THERMOFLUID

CHAPTER 2: FLUID APPLICATION

2.3.6 Energy of a Flowing Fluid

a. Potential energy Potential energy per unit weight = z

b. Pressure energy (Pressure Head)

Pressure energy per unit weight = =

c. Kinetic energy
²
Kinetic energy per unit weight =
2
²
Total energy per unit weight = z + +
2

2.3.7 Bernoulli Theorem
Total energy per unit weight at section 1 = Total energy per unit weight at section 2

The limits of Bernoulli’s Equation Bernoulli’s Equation is the most important and useful equation in fluid
mechanics. It may be written,

Example 2.7

Water flows through a pipe 36 m from the sea level as shown in figure a. Pressure in the pipe is 410 kN/m2 and
the velocity is 4.8 m/s. Calculate total energy of every weight of unit water above the sea level.

Figure 2.6
Solution:

²
∑ = z + +
2
410 × 10³ 4.8²
= 36 + +
9810 19.62
= 78.96
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