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. T

    Speed usage in Lattice Boltzmann Method

    One thing that confuses me is the physical speed and sound speed. The lattice sound speed cs=1/sqrt{3} corresponds to the physical sound speed for isothermal flow (sqt{RT}). Why isn't the physical speed (e.g. inlet speed up of lid cavity) converted and use accoringly? $$c_p=\sqrt{RT}≈330m/s...
  2. Roy S Ramirez

    Measuring the Discharge Coefficients of a Rocket Injector

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  3. L

    I Optimal Copper Pipe Size for Misting System

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  4. WhiteWolf98

    Fluid Dynamics - Mass Conservation, State Equation for an Ideal Gas

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  5. R

    Circulation of water in a cylindrical reservoir

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  6. S

    Help with Bernoulli's equation for a central heating system

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  7. X

    Would acceleration under water affect the person?

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  8. Roy S Ramirez

    How can I predict the flow rate for a real life water hose?

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  9. D

    Air Compressor Model Analysis

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  10. S

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  11. WhiteWolf98

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  12. C

    I Trying to better understand what viscosity really is

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  13. L

    I Massive Particles in Sonic & Slow Light Black Holes

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  14. T

    Normal Stress Balance at a Fluid-fluid Interface

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  15. Raihan amin

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  16. Roy S Ramirez

    How many O-rings would a mechanical engineer use here?

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  17. Hawkingo

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  18. J

    Lubrication theory for two spheres -- Finding the resisting force

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  19. P

    Is this kind of pressure chamber design possible?

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  20. Juanmdq

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  21. ikihi

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  22. Sizhe

    Pipe flow with precipitation at boundary

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  23. L

    Other Asking for recommendation on Fluid Dynamics and CFD textbooks

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  24. A

    Calculating the velocity and pressure profiles across an axial fan

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  25. A

    At what critical Reynolds number does vortex shedding begin?

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  26. J

    MHB Pressure and Force - Fluid Dynamics

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  27. F

    Is Bernoulli's Equation Applicable for Finding Pressure in Hydraulics Problems?

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  28. K

    How to calculate effective pump flow-rate across a filter?

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  29. P

    Other Ideas for a Physics Project (Fluid Dynamics)

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  30. runningman19

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  31. Domenico94

    Speed of fluid in a turbulent flow

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  32. Julian Erickson

    I Rocket-Jet Hybrid, Rocket + Ramjet

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  33. Domenico94

    I How does a fluid behave inside of a spherical cavity?

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  34. B

    Model pressure loss vs time for air in a cylinder w/ hole

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  35. F

    Solving Fluid Dynamics in Syringe: Magnitude & Pressure

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  36. I

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

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  37. M

    When will the barrel become half empty?

    Homework Statement [/B] I'm not a native english speaker, so I apologize if my explanations are a bit awkward. I do not have a solution to this problem and I'd be grateful if someone could check this/help. I also have absolutely no idea how to even begin. Asked my colleagues, none of them know...
  38. A

    I How Does a Pressurized Tank Empty Over Time Through a Hole?

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  39. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 1: Introduction and Fundamental Concepts - I

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 1: Introduction and Fundamental Concepts - I

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  40. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 2: Introduction and Fundamental Concepts - II

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 2: Introduction and Fundamental Concepts - II

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  41. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 3: Introduction and Fundamental Concepts - III

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 3: Introduction and Fundamental Concepts - III

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  42. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 4: Fluid Statics Part - I

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 4: Fluid Statics Part - I

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  43. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 5: Fluid Statics Part - II

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 5: Fluid Statics Part - II

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  44. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 6: Fluid Statics Part - III

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 6: Fluid Statics Part - III

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  45. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 7: Fluid Statics Part - IV

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 7: Fluid Statics Part - IV

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  46. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 8: Fluid Statics Part - V

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 8: Fluid Statics Part - V

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  47. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 9: Fluid Statics Part - VI

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 9: Fluid Statics Part - VI

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  48. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 10: Kinematics of Fluid Part - I

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 10: Kinematics of Fluid Part - I

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  49. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 11: Kinematics of Fluid Part - II

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 11: Kinematics of Fluid Part - II

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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  50. Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 12: Kinematics of Fluid Part - III

    Fluid Mechanics by Prof. S.K. Som (NPTEL):- Lecture 12: Kinematics of Fluid Part - III

    Copyright strictly reserved to Prof. Som and NPTEL, Govt. of India. Duplication prohibited. Lectures: http://www.nptel.ac.in/courses/105101082/ Syllabus: http://www.nptel.ac.in/syllabus/105101082/
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