Matter :- Anything that has mass and occupy space.

Basically matter of two types Solids and Fluids.

Solids :- Solids are substance that have finite deformation under the action of shear force and will try to regain its original position after removal of load.

Enough amout of loading

It will try to regain its original position.

Finite deformation.

1.Rigid Solid – Strong intermolecular force .

2.Deformable Solid – Weak intermolecupar force .

Fluids :-Fluid is a substance which is capable of flowing under action of shear force ( However small force may be )  OR

Fluid are the substance that deform continuously under the action of shear force (no matter how it small it is )

◆ Liquid & Gases are example of fluids.

◆ Fluids are called zero memory substance 1

1. Liquids :- Liquids have free surface ,No shape

2.Gasses :- Gases does not have free surface,Gases dont have size,No Shape

Properties Of Fluid :-

1.Density (९) :- ( Mass Density )

The density of fluid is defined as its mass per unit volume.                               Density = (Mass / Volume ).                                    =(m/v).          Unit -Kg/m^3.   

◆ Density of liquid is always constant .     ◆ Density of gases are function of Pressure & Temperature .  (when temerature increase   density decreases ,when pressure increases density also increases ) 

                      

Density of water is – 1000 kg/m^3.               Density of Mercury – 13500:Kg/m^3.         Density of oil – 800-850 Kg/m^3

2. Weight Density (w):- ( Specific weight )

Specific weight of liquid is defiend as weight per unit volume at standard temperature and pressure .                      w = (weight/volume)

w = (m×g)/v

w = ९×g

g – Accleration due to gravity.

Unit = ( N/m^3)

3. Specific Volume (Vs) :-

Specific volume is defiend as the volumenper unit weight.

4. Specific gravity / Relative density (s) :-

The ratio of specific weight of fluid to the specific weight of pure water at standard temperature and pressure is called as specific gravity.

5. Compressibility :- Compressibility gives idea how a fluid changes its volume when subjected to change  pressure or force

Compressibility = (fractional change in volume/change in pressure)

Unit- (m^2/N)

6. Viscosity:- Viscosity is resistance offered by one layer of fluid to another layer of fluid.

Newtons law of Viscosity :- states that the viscous force (F) between two parallel layers of a fluid is directly proportional to the velocity gradient (dv/dy) and the coefficient of viscosity (η), and inversely proportional to the distance between the layers (dy).

F = -η * (dv/dy) * A

Where:

F – viscous force.

η – (eta)coefficient of viscosity, (a measure of a fluid’s internal resistance to flow.)

dv/dy – velocity gradient, ( representing the change in velocity with respect to distance. )

A – cross-sectional area through which the fluid is flowing.

Dynamic Viscosity (η):

Dynamic viscosity defined as the ratio of the shear stress (τ) to the velocity gradient (du/dy) in a fluid.

η = τ / (du/dy)

Units: pascal-second (Pa·s) = kg/(m·s). = poise (P), where 1 P = 0.1 Pa·s.

Kinematic Viscosity (ν):(nu)

Kinematic viscosity is the ratio of dynamic viscosity (η) to the density (ρ) of the fluid.

It is a measure of a fluid’s resistance to flow relative to its density and is used to characterize how quickly a fluid spreads. ν = η / ρ

Units: square meter per second (m²/s). centistokes (cSt) in practical where 1 cSt = 1 x 10^(-6) m²/s.

Surface tension (σ):-

Surface tension is a property of liquids that arises due to the cohesive forces between the molecules at the surface of the liquid.

It’s a measure of the tendency of liquid molecules to stick together and resist being separated.

σ = F / L

σ – surface tension in N/m.

F – force acting perpendicular to a line of unit length at the liquid’s surface.

L – length of that line.

Unit – N/m. T

Capillary action, also known as capillarity or capillary rise, is the phenomenon where liquids move against the force of gravity within a narrow space, such as a thin tube or a porous material. This movement occurs due to the combined effects of adhesive and cohesive forces within the liquid and between the liquid and the solid surface.

Here’s a detailed explanation of capillary action:

1. Adhesive Forces: Adhesive forces are the attractive forces between the liquid molecules and the molecules of the solid surface in contact with the liquid. If the liquid wets the surface (meaning it spreads out and adheres to it), the adhesive forces are stronger. Water, for instance, wets glass, so it climbs up the walls of a thin glass tube.
2. Cohesive Forces: Cohesive forces are the attractive forces between the molecules within the liquid itself. These forces tend to keep the liquid molecules together. In the case of water, hydrogen bonding between water molecules creates strong cohesive forces.
3. Capillary Tube: Capillary action often occurs in thin tubes or capillaries. The term “capillary” itself refers to these small-diameter tubes. The smaller the diameter of the tube, the higher the liquid can rise due to capillary action.
4. Balancing Forces: In a narrow tube, the liquid rises until the upward force due to cohesive and adhesive forces is balanced by the downward force of gravity. The shape of the liquid meniscus (the curve at the liquid’s surface in the tube) depends on the balance between these forces.
5. Contact Angle: The angle at which the liquid meets the surface (contact angle) also plays a crucial role. If the contact angle is small, the liquid wets the surface better, resulting in a higher capillary rise. Conversely, if the contact angle is large, the rise will be limited.
6. Height of Capillary Rise: The height to which a liquid will rise in a capillary tube is inversely proportional to the tube’s radius (r) and directly proportional to the liquid’s surface tension (σ), the contact angle (θ), and the density (ρ) of the liquid. The equation for capillary rise is given by:h = (2σcosθ) / (rρg)Where:
   • h is the height of capillary rise.
   • σ is the surface tension of the liquid.
   • θ is the contact angle.
   • r is the radius of the capillary tube.
   • ρ is the density of the liquid.
   • g is the acceleration due to gravity.

Capillary action has various practical applications, such as in plant roots drawing water from the soil, in ink pens, and in medical devices like capillary tubes for blood analysis. It’s a fascinating phenomenon that results from the delicate interplay of molecular forces and geometry.

such as viscosity, vapour pressure, compressibility,
surface tension, capillarity, Mach number etc., pressure at a point in the static mass of fluid,
variation of pressure, Pascal’s law, pressure measurement by simple and differential
manometers using manometric expression.

Fluid Statics
Hydrostatic forces on the plane and curved surfaces, center of pressure, Buoyancy, center of
buoyancy, stability of floating bodies, metacenter and metacentric height its application in
shipping.

Unit 3: Fluid Kinematics [08 Hours]
Velocity of fluid particle, types of fluid flow, description of flow, continuity equation,
Coordinate freeform, acceleration of fluid particle, rotational and irrotational flow, Laplace’s
equation in velocity potential and Poisson’s equation in stream function, flow net.

Fluid Dynamics
Momentum equation, development of Euler’s equation, Introduction to Navier-Stokes
equation, Integration of Euler’s equation to obtain Bernoulli’s equation, Bernoulli’s theorem,
Application of Bernoulli’s theorem such as venturimeter, orifice meter, rectangular and
triangular notch, pitot tube, orifices, etc.

Types of Flow
a) Laminar Flow: Flow through circular pipe, between parallel plates, Power absorbed in
viscous flow in bearings, loss of head due to friction in viscous flow.
b) Turbulent Flow: Reynolds’s experiment, frictional loss in pipe flow, shear stress in
turbulent flow, major and minor losses, HGL and TEL, flow through series and parallel
pipes.

Dimensional Analysis
a) Dimensional Analysis: Dimensional homogeneity, Raleigh’s method, Buckingham’s
theorem, Model analysis, similarity laws and dimensionless numbers.
b) Introduction to boundary layer theory and its analysis.
c) Forces on Submerged bodies: Drag, lift, Drag on cylinder, Development of lift in
cylinder.