Kinematics and Dynamics of Flow

Kinematics and dynamics of flow are some of the basic aspects of fluid mechanics. Kinematics of flow deals with the motion of the fluid without considering the factors that are affecting the motion. On the other hand, fluid dynamics focuses on the factors that are affecting fluid motion, for example, pressure, momentum, force, etc. Fluid dynamics is based upon the conservation of energy theory, which gives us the formula of Bernoulli’s equation or the continuity equation. On the basis of the characteristics, the flow of these fluids is classified into several categories. For example, steady and unsteady flow, laminar and turbulent flow, uniform and non-uniform flow, etc.

KINEMATICS AND DYNAMICS OF FLOW:

Kinematics and Dynamics of flow are one of the major topics of fluid mechanics. Mechanics of the flow is the study of the motions in the fluid, like velocity, viscosity, acceleration, etc., irrespective of the forces that are causing that motion. The concept covered under the kinematic study of flow is acceleration, velocity, flow rate, and nature of a fluid flow. The dynamics of the flow, also called fluid dynamics, is the study of the forces and the factors that are affecting the flow of a fluid. Fluid dynamics is used for studying the force, pressure, and mass flow rate of the fluid. The flow is also classified into various categories as per their characteristics. For example, steady and unsteady flow, uniform and non-uniform flow, etc.

TYPES OF FLOW:

The Kinematics and dynamics of flow have described several types of flow:

• Study and a steady flow: A steady flow is defined as the flow whose fluid characteristics like velocity, pressure, density, etc., do not change with respect to that of time. In contrast, unsteady flow is defined as a fluid whose over fluid characteristics change with respect to time.
• Uniform and non-uniform flow: A uniform flow is defined as the type of flow in which the velocity at a given time does not change with respect to the space, i.e., length of direction. Ananya form flow is defined as the type of flow in which the flow velocity does not change with respect to space.
• Laminar and turbulent flow: in a laminar flow. The fluid particles flow in a definite path or streamline, whereas, in a turbulent flow, the fluid particle moves in zig-zag or random motion.
• Rotational and irrotational flow:
• Compressible and incompressible flow: In a compressive flow, the density of the fluid changes with time, whereas in an incompressible flow, density changes at any instant.

KINEMATICS AND DYNAMICS OF FLOW FORMULA:

Kinematics and dynamics of the flow formula represent the motion in the fluid. The formula on the basis of the kinematics and dynamics of flow are:

• Rate of flow or Discharge: The flow or discharge rate is defined as the fluid flowing per second through a section of pipe or a channel. It is denoted by the letter Q. Discharge of the flow totally depends upon the area of the cross-section of the pipe or the channel through which the fluid is passing by and the velocity of the flow. Mathematically, the rate of flow/Discharge is expressed as,

Q=A*V

• Bernoulli’s equation: Bernoulli’s equation is used for representing the relationship between the velocity and pressure of the fluid. As per the definition, the Bernoulli equation must be constant for the sum of the total heads, i.e., the pressure head, the kinetic head, and the potential head. Mathematically, Bernoulli’s equation is expressed as:

 P+12V2+gh=constant

KINEMATICS AND DYNAMICS OF FLOW EXAMPLES:

The kinematics and dynamics of flow examples represent various fluid mechanics applications. Several applications of these fluid mechanics are,

• Venturi metre.
• Orifice metre.
• Pilot Tube.

Flow dynamics are also used in several other applications, for example,

• It is also used for determining any kind of leakage in any section.
• For measuring the force acting on an aircraft.
• Determination of the pressure in the pipeline.

CONCLUSION:

Kinematics and dynamics of a flow are some of the basic topics of fluid mechanics. Kinematics of fluid deal with the motion of the fluid, for example, velocity, acceleration, viscosity, etc. In contrast, the dynamics of a flow focuses on the factors affecting the fluid motions, like pressure, moment, force, etc. The fluid mechanics defines the various types of flows like steady flow and unsteady flow, laminar and turbulent flow, rotational and irrotational flow, etc. Kinematics and dynamics of flow postulated several equations to determine several characteristics of the motion of the fluid. To understand the concept of kinematics and dynamics of flow, it is required to have the basic knowledge of the Lagrangian Approach and Eulerian Approach.