Some of the most common used technical terms used in fluid mechanics
Acoustic theory
Relating to mathematical description of sound waves.
Acoustical Engineering - Explains to architects and engineers the basic science of acoustics. Introduction to sound, decibel and propagation of sound. Calculate decibels, reduce noise in HVAC systems, sound levels ..
Aerodynamics
Aerodynamics is the study of the flow of gases.
The Ideal Gas Law - For a perfect or ideal gas the change in density is directly related to the change in temperature and pressure as expressed in the Ideal Gas Law.
Aeronautics
Aeronautics is the mathematics and mechanics of flying objects, in particular airplanes.
The boundary layer is the layer of fluid in the immediate vicinity of a bounding surface.
Dynamic, Absolute and Kinematic Viscosity - An introduction to dynamic, absolute and kinematic viscosity and how to convert between CentiStokes (cSt), CentiPoises (cP), Saybolt Universal Seconds (SSU) and degree Engler.
Cavitations
Cavitation and NPSH - An introduction to cavitation and Net Positive Suction Head, NPSH.
In a compressible flow the compressibility of the fluid must be taken into account.
The Ideal Gas Law - For a perfect or ideal gas the change in density is directly related to the change in temperature and pressure as expressed in the Ideal Gas Law.
Properties of Gas Mixtures - Special care must be taken for gas mixtures when using the ideal gas law, calculating the mass, the individual gas constant or the density.
The Coanda Effect is the tendency of a stream of fluid to stay attached to a convex surface, rather than follow a straight line in its original direction.
Conservation laws
The conservation laws states that particular measurable properties of an isolated physical system does not change as the system evolves.
In fluid dynamics, the Euler equations govern the motion of a compressible, inviscid fluid. They correspond to the Navier-Stokes equations with zero viscosity, although they are usually written in the form shown here because this emphasizes the fact that they directly represent conservation of mass, momentum, and energy.
Euler Number
The Euler Number - An introduction to and a definition of the Euler Number.
Fluid Flowmeters - Tools and information regarding fluid flowmeters.
Fluid Flow Measurement - An introduction to different types of fluid flowmeters - Orifices, Venturies, Nozzles, Rotameters, Pitot Tubes, Calorimetrics, Turbine, Vortex, Electromagnetic, Doppler, Ultrasonic, Thermal, Coriolis.
Fluids
The Bernoulli Equation - A statement of the conservation of energy in a form useful for solving problems involving fluids. For a non-viscous, incompressible fluid in steady flow, the sum of pressure, potential and kinetic energies per unit volume is constant at any point.
Laminar, Transitional or Turbulent Flow? - It is important to know if the fluid flow is laminar, transitional or turbulent when calculating heat transfer or pressure and head loss.
Froude number
The Froude Number - An introduction to and a definition of the Froude Number.
Gas
The Ideal Gas Law - For a perfect or ideal gas the change in density is directly related to the change in temperature and pressure as expressed in the Ideal Gas Law.
Properties of Gas Mixtures - Special care must be taken for gas mixtures when using the ideal gas law, calculating the mass, the individual gas constant or the density.
Hydraulics is a branch of science and engineering concerned with the use of liquids to perform mechanical tasks.
Hydrodynamics
Hydrodynamics is the fluid dynamics applied to liquids, such as water, alcohol, and oil.
Ideal Gas
The Ideal Gas Law - For a perfect or ideal gas the change in density is directly related to the change in temperature and pressure as expressed in the Ideal Gas Law.
Properties of Gas Mixtures - Special care must be taken for gas mixtures when using the ideal gas law, calculating the mass, the individual gas constant or the density.
Used by modelers who wish to non dimensionless speed
Laminar Flow
Laminar, Transitional or Turbulent Flow? - It is important to know if the fluid flow is laminar, transitional or turbulent when calculating heat transfer or pressure and head loss.
Laplace's equation
Describes the behavior of gravitational, electric, and fluid potentials.
Lift (force)
Lift consists of the sum of all the aerodynamic forces normal to the direction of the external airflow.
When an object travels through a medium, then its Mach number is the ratio of the object's speed to the speed of sound in that medium.
The Mach Number - An introduction to and a definition of the Mach Number.
Navier-Stokes Equations
The motion of a non-turbulent, Newtonian fluid is governed by the Navier-Stokes equation. The equation can be used to model turbulent flow, where the fluid parameters are interpreted as time-averaged values.
Newtonian Fluid
A fluid is Newtonian if viscosity is constant applied to shear force.
Dynamic, Absolute and Kinematic Viscosity - An introduction to dynamic, absolute and kinematic viscosity and how to convert between CentiStokes (cSt), CentiPoises (cP), Saybolt Universal Seconds (SSU) and degree Engler.
Non-Newtonian fluid
Non-Newtonian fluid viscosity changes with the applied shear force.
Prandtl number
Prandtl Number is a Dimensionless number approximating the ratio of momentum diffusivity and thermal diffusivity.
Pressure
What is Pressure? - An introduction to pressure, a definition and a presentation of common units as psi and Pa, and the relationship between them.
Reynolds Number
The Reynolds Number - An introduction to and a definition of the dimensionless Reynold's Number.
A shock wave is a strong pressure wave produced by explosions or other phenomena that create violent changes in pressure.
Sound barrier
The sound barrier is the apparent physical boundary stopping large objects from becoming supersonic.
The Mach Number - An introduction to and a definition of the Mach Number.
Speed of Sound - Speed of sound in air, fluids and solids. Formulas and values for different materials.
Streamline - Stream function
a streamline is the path that an imaginary particle would follow if it was embedded in the flow.
Strouhal number
The Strouhal number is a quantity describing oscillating flow mechanisms.
The Strouhal Number - An introduction to and a definition of the Strouhal Number.
Supersonic Flow
Flow with speed above the speed of sound, 1,225 km/h at sea level, is said to be supersonic.
The Mach Number - An introduction to and a definition of the Mach Number.
Speed of Sound - Speed of sound in air, fluids and solids. Formulas and values for different materials.
Surface tension
Surface tension is a force within the surface layer of a liquid that causes the layer to behave as an elastic sheet.
Transonic
Flow with speed at velocities just below and above the speed of sound is said to be transonic.
The Mach Number - An introduction to and a definition of the Mach Number.
Turbulent Flow - Turbulence
Laminar, Transitional or Turbulent Flow? - It is important to know if the fluid flow is laminar, transitional or turbulent when calculating heat transfer or pressure and head loss.
Vapor pressure
For a particular substance at any given temperature there is a pressure at which the vapor of that substance is in equilibrium with its liquid or solid forms.
Velocity
The Bernoulli Equation - A statement of the conservation of energy in a form useful for solving problems involving fluids. For a non-viscous, incompressible fluid in steady flow, the sum of pressure, potential and kinetic energies per unit volume is constant at any point.
Venturi
A Venturi is a system for speeding the flow of the fluid, by constricting it in a cone-shaped tube.
Viscosity
Dynamic, Absolute and Kinematic Viscosity - An introduction to dynamic, absolute and kinematic viscosity and how to convert between CentiStokes (cSt), CentiPoises (cP), Saybolt Universal Seconds (SSU) and degree Engler.
Fluid Mechanics The study of fluids - liquids and gases. Involves various properties of the fluid, such as velocity, pressure, density and temperature, as functions of space and time.
