What is Fluid dynamic: Definition and 90 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. SherLOCKed

    Increase in the frequency of sound in a glass of water?

    Suppose you have a glass of water, and you beat a spoon on the bottom layer of glass through the mouth of glass, repeated beatings in a regular fashion will cause in increased frequency of sound produced due to the spoon beating?What causes such increase in frequency?
  2. B

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  3. Rahulx084

    Transport Phenomenon: Drag Coefficient & Friction Factor

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  4. I

    How long will it take for a gas cylinder to empty?

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  5. Gabriele99

    Will water flow ever stop if we increase resistance?

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  6. JorgeM

    I Is this expression for Mass Flowing Out of a Bottle correct?

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  7. K

    Hydrostatic pressure distribution despite fluid motion

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  8. T

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  9. JorgeM

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  10. helppls

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  11. T

    Non Newtonian / Newtonian Fluid interface

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  12. mkematt96

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  13. T

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  14. E

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  15. S

    Business major.... fluid dynamics question....

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  16. T

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  17. D

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  18. T

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  19. S

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  20. F

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  21. C

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  22. P

    Volume Flux for a Hydraulic Jump

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  23. M

    I Will a Dense Green Object Sink in a Sealed Water-Filled Pipe?

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  24. J

    Can a piezoelectric create dynamic pressure in oil fluid for energy harvesting?

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  25. R

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  26. C

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  27. S

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  28. J

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  29. A

    Fluid Dynamics - Water Storage Tank

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  30. Arsen

    Fluid Dynamic. Force on particles in carrying fluid (liquid)

    Good day to all! I have a question : We have a flowing fluid ( liquid ) with known pressure, flow in the pipe ( pump is pumping it). There are some spherical microparticles in the liquid, let's say 10-15 microns. I want to create force to stop them moving! Will the pressure force be in the form...
  31. L

    How to Determine Flow Rate in a Pipe Using Fluid Dynamics?

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  32. B

    Fluid Dynamic Torque [in symbols]

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  33. I

    Calculating Fluid Dynamic Forces on a Towing Cable

    I am trying to develop a calculator to approximate the depth of a trolling rig used by fisherman, which is typically a lead weight with a hook (jighead), attached to a single plastic/rubber shad body (http://www.tacklecoveshop.com/images/Product/icon/1734.jpg). The other typical rig is a...
  34. P

    Basic Fluid Dynamic Question (Oil Return on Turbocharged Car)

    Ok-I'm actually looking to settle an argument on another forum. I have turbocharged my 1979 Volvo 240, and converted to a later style motor. Instead of drilling and tapping the boss in the block for my oil return to the oil pan, I welded a 1/2" NPT bung into my oil pan. The approximate inner...
  35. G

    Solving Fluid Dynamics Problem: Granite Floating in Mercury & Water

    Hi I am solving some problems in fluid dynamics I came to this problem that I don't understand how to solve it. A piece of granite floats at the interface of mercury and water contained in a beaker (Fig.). If the densities of granite, water and mercury are ρ, ρ1 and ρ2 respectively, the...
  36. M

    Solving Fluid Dynamics Question on Droplet Shape

    Hi everyone. I've been out of college for some time and forgot how to determine the shape of a droplet. I know how to determine the contact angle based on the interracial energies of three mediums, but I'm not sure how to calculate the actual shape of the hanging drop. In my scenario I have a...
  37. A

    An equation in fluid dynamic ~ me ~

    When I studied the fluid dynamic , I saw a quite hard equation (typed in attached file) , I don't know how to prove it , maybe there's a somehow relationship between this eq with Gauss's Divergence Theorem ... Can anyone help me ?
  38. J

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    Hallo. I am new at forum, could please somebody send me a code for fluid dynamic in 3D written in Scilab, mathematica or Fortran. I will use it to start with learning!b Thaks, JG
  39. H

    Fluid Dynamic: Stokeslet? Rotlet?

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  40. A

    My fluid dynamic project, i need explenation

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