ABSTRACT / SUMMARY

In this experiment, the main purpose is to investigate the validity of the Bernoulli

equation when applied to the steady flow of water in a tapered duct. In addition, flow rates

and both static and total pressure heads in a rigid convergent or divergent tube of known

geometry for a range of steady flow rates also measured. Bernoulli’s Theorem Demonstration

Unit (Model: FM 24) is used in order illustrates those circumstances to which Bernoulli's

Theorem may be applied. For this experiment, the pressure difference is taken from tapping

point A to tapping point F. The time taken for the water to fill up the water tank up to 3 liter

also recorded. Then, the flow rate, velocity, dynamic head and total head can be calculated by

using the data obtained. Based on the results, it can be conclude that for both convergent and

divergent flow, the total head pressure increase. This is valid for the Bernoulli’s theorem for a

steady flow of water and the velocity increased along the same channel. In addition, the flow

rates and both static and total head pressure in a rigid convergent or divergent of known

geometry for a range of steady flow rates are also calculated. The flowrates increased in all

the three flow of the experiment. The total pressure head increases neither convergent nor

divergent flow.

INTRODUCTION

Nowadays, fluid mechanics has established itself as an analytical field from the use of the

traditional laws of statics, dynamics, and thermodynamics to circumstances whereby fluids

may be treated as continuous media. The laws affiliated with this are conservation of mass,

energy, and momentum. Bernoulli theorem in fluid mechanics is the relation among the

pressure, velocity, and elevation in a moving fluid, in which, we assumed that the

compressibility and viscosity of the fluid are negligible and the flow is steady.

Daniel Bernoulli (1700-1782), Swiss mathematician, claims that for an inviscid flow,

an increase in the speed of the fluid happens concurrently with a decrease in pressure or a

decrease in the fluid’s potential energy. This is known as Bernoulli’s theorem or Bernoulli’s

principle. For example, in a horizontal pipe, the highest fluid pressure is in the section where

the fluid’s speed is the lowest, while the lowest fluid pressure is in the section where the

fluid’s speed is the highest.

In industry, the fluid’s speed can be determined by utilizing a device such as venturi

meter or an orifice plate where it is placed into the pipeline to lower the diameter of the flow.

For an incompressible fluid flowing in horizontal device, the reduction in the diameter will

cause the fluid’s speed to increase thus reducing the pressure. This phenomenon is known as

the venture effect. Bernoulli’s principle corresponds to the principle of the conservation of

energy. In a steady flow, the sum of all forms of mechanical energy along the streamline is

the same at all points. Thus, allow us to understand the Bernoulli’s principle.

Figure 1: Venturi tube

AIMS / OBJECTIVES

1. To investigate the validity of the Bernoulli equation when applied to the steady flow

of water in a tapered duct.

2. To measure flow rates and both static and total pressure heads in a rigid convergent or

divergent tube of known geometry for a range of steady flow rates.