What is Fluid dynamics: Definition and 631 Discussions

In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids—liquids and gases. It has several subdisciplines, including aerodynamics (the study of air and other gases in motion) and hydrodynamics (the study of liquids in motion). Fluid dynamics has a wide range of applications, including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, understanding nebulae in interstellar space and modelling fission weapon detonation.
Fluid dynamics offers a systematic structure—which underlies these practical disciplines—that embraces empirical and semi-empirical laws derived from flow measurement and used to solve practical problems. The solution to a fluid dynamics problem typically involves the calculation of various properties of the fluid, such as flow velocity, pressure, density, and temperature, as functions of space and time.
Before the twentieth century, hydrodynamics was synonymous with fluid dynamics. This is still reflected in names of some fluid dynamics topics, like magnetohydrodynamics and hydrodynamic stability, both of which can also be applied to gases.

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  1. M

    Calculating Air Pipe Flow System Rates & Velocities

    I'm working in an engineering internship after my first year and we haven't covered fluid dynamics in my program yet. I've been assigned to find flow rates and velocities in several branches of a suction (dust collection) system in our factory. The main branch has a diameter of 30" and is...
  2. SurajBahuguna

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  3. S

    Contradictions in Irrotational Vortex?

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  4. ManicPIxie

    Bernoulli, Fluid Dynamics, and ships

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  5. C

    Fluid dynamics, mass flow rate

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  6. M

    (Fluids) Difference in stress or pressure between setups?

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  7. Nabil

    101 in air flow dynamics please?

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  8. D

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  9. I

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  10. S

    Effect Pressure In Main tube due to outlets

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  11. Feodalherren

    Computational fluid dynamics: steady 2D flow

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  12. P

    Can liquids be treated as rigid bodies for moment of inertia

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  13. Feodalherren

    Fluid Dynamics: Conservation of momentum equation

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  14. Wyn

    Other Intr. Fluid Mech. for Physicists and Mathematicians by Pert

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  15. A

    Fluid dynamics question (Poiseuille)

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  16. T

    Fluid dynamics - find velocity of a particle in a vector fie

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  17. E

    Comparison between CFD results and experimental data

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  18. K

    Determine the launching speed of the object

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  19. arthurchen

    Laminar flow exits an inclined tube

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  20. N

    Roman Inverted Siphons and Fluid Dynamics

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  21. H

    Modeling: Light irradiance and spatio-temporal decay

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  22. U

    Navier Stokes Equation - Flow of waves

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  23. A

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  24. A

    Fluid dynamics: Reynolds Number, Drag Constant

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  25. A

    Fluid dynamics: head losses and pressure

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  26. M

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  27. AdityaDev

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  28. AdityaDev

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  29. AdityaDev

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  30. A

    Does anyone know this equation? (fluid dynamics, Stokes law)

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  31. S

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  32. Strangelet

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  33. H

    Can applied physicists be CFD analysts

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  34. T

    Fluid Dynamics - Rate of Change of Momentum question

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  35. K

    Approximating Windshield Shape of a Car: Velocity at Points A & B

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  36. P

    Schools Computational Fluid Dynamics in Physics Graduate School

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  37. S

    Wind Speed & Heat: Is There a Constant?

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  38. G

    Jetski propulsion analysis (fluid dynamics)

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  39. L

    Fluid dynamics problem -- Tanks Connected by Capillary

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  40. F

    Calculating Minor Head Losses in a Fluid System

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  41. C

    Fluid dynamics - find distribution of a conserved variable

    I accidentally posted this to the "Calculus & Beyond" forum when I meant to post it to the physics forum. If someone can tell me how to move this post, I will get rid of it here! Homework Statement Consider a property, for example temperature θ, that is conserved during advection (i.e. Dθ/Dt =...
  42. F

    Calculating Minor Head Losses for Pumped Liquid System | Fluid Dynamics Question

    I have a question where I have to find minor head losses for a system using both the equivalent length method and number of velocity heads method . It will not let me attatch the drawing here but , a liquid is to be pumped from an underground vessel (which is vented) to a pressurissed...
  43. G

    Optics and fluid dynamics simulation software

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  44. F

    Fluid Dynamics Question - Pressure Difference in Horizontal Pipe

    Homework Statement The Trans-Alaska Pipeline System (TAPS) carries around 100,000m3 of oil per day from the Northern Alaskan oil fields to the nearest ice-free port of Valdez, around 1300km away. The pipe has an outer diameter of 1.22m and a wall thickness of 12mm. Eleven pumping stations...
  45. Z

    Need help for a CFD(computational fluid dynamics) software

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  46. crador

    Fluid Dynamics pipeline with a venturi injector

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  47. mattyboson12

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  48. K

    Analogy between fluid dynamics and electromagnetism

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  49. B

    Fluid dynamics in horizontal pipe

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  50. N

    Solving Fluid Dynamics Pressure at Different Speeds

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