## What is Hydraulic Engineering?

The movement and transportation of fluids, especially water and sewage, is the focus of hydraulic engineering. One of these systems’ unique features is the extensive utilization of gravity as the driving factor for fluid movement. Civil engineering includes bridges, dams, channels, canals, and levees, as well as sanitary and environmental engineering.

Hydraulic engineering is the application of fluid mechanics ideas to water collection, storage, control, transport, regulation, measurement, and consumption concerns. The hydraulic engineer creates conceptual designs for numerous water-related elements, such as dam spillways and outlet works, highway culverts, irrigation canals and related structures, and thermal power plant cooling-water facilities.

## Fluid Mechanics

Fluid mechanics is the discipline of science that studies the behavior of fluids while in motion or at rest. Whether the fluid is at rest or in motion, it is susceptible to a variety of forces and external variables, as we all know. It responds in these situations in accordance with its physical features. Fluid mechanics is concerned with three elements of the fluid: statics, kinematics, and dynamics.

Fluid statics: This studies the fluid in a state of rest

Fluid kinematics: Fluid kinematics: “moving fluid” refers to fluid in motion, and fluid kinematics is the study of it.

Fluid dynamics is the study of the effect of all pressures, including external pressures, on a moving fluid.

## PROPERTIES OF FLUID

MASS DENSITY (ρ)

The amount of fluid contained in a unit volume.

SPECIFIC VOLUME (v)

The fluid’s volume per unit mass.

SPECIFIC WEIGHT (w)

since W = mg and ρ = m/ V

SPECIFIC GRAVITY (S)

The dimensionless of the specific weight (or density) of a fluid to the specific weight ( or density) of a standard fluid.

VISCOSITY (μ)

DYNAMIC VISCOSITY (μ)

The property of fluid which determines the amount of its resistance to shearing stress, τ

Unit Conversion

KINEMATIC VISCOSITY (ϒ)

The ratio of a fluid’s dynamic viscosity to its density.

Unit Conversion

FORCE (F)

POWER (P)

### PROBLEM WITH VISCOSITY FOR SHAFT TYPE

VELOSITY SHAFT (u)

FORCE (F)

TORQUE ON SHAFT (T)

POWER ON SHAFT (P)

### CONICAL BEARING VISCOSITY PROBLEMS

ANGULAR VELOSITY (ω)

ANGLE (θ)

POWER (P)

THICKNESS OF OIL (h)

## CAPILLARITY

LIQUID HEIGHT IN TUBE (h)

## SURFACE TENSION

LIQUID DROPLET PRESSURE (P)

PRESSURE IN BUBBLE (P)

PRESSURE IN LIQUID JET (P)

CONTINUITY EQUATION

BERNOULLI’S EQUATION

COEFFICIENT OF DISCHARGE

COEFFICIENT OF VELOCITY

DISCHARGE OF VENTURIMETER & ORIFICEMETER

## MOMENTUM EQUATION

FORCE ACTING IN X- DIRECTION

FORCE ACTING IN Y- DIRECTION

RESULTANT FORCE

MOMENT OF MOMENTUM EQUATION

## FLOW THROUGH CIRCULAR CONDUITS

TOTAL ENERGY LINE (TEL)

HYDRAULIC ENERGY LINE (HEL)

HAGEN POISEUILLE’S EQUATION

SHEAR STRESS

VELOCITY

MAXIMUM VELOCITY

AVERAGE VELOCITY

THE RATIO BETWEEN MAXIMUM VELOCITY & AVERAGE VELOCITY

DISCHARGE

PRESSURE DIFFERENCE

DARCY  WEISBACH EQUATION

MAJOR LOSS IN PIPES

### MINOR LOSS IN PIPES

LOSS DUE TO SUDDEN ENLARGEMENT

LOSS DUE TO SUDDEN CONTRACTION

LOSS AT PIPE ENTRANCE

LOSS AT PIPE EXIT

LOSS AT BEND OF PIPE

LOSS AT DUE TO VARIOUS FITTINGS

LOSS AT DUE TO OBSTRUCTION

DISCHARGE

EQUIVALENT PIPE

### BOUNDARY LAYER

DISPLACEMENT THICKNESS

MOMENTUM THICKNESS

MOMENTUM THICKNESS

SHEAR STRESS

DRAG FORCE

LOCAL COEFFICIENT OF DRAG

AVERAGE COEFFICIENT OF DRAG

### BLASIUS’S SOLUTION

BOUNDARY LAYER THICKNESS

LOCAL COEFFICIENT OF DRAG

AVERAGE COEFFICIENT OF DRAG