Convection Definition and 194 Threads

Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convection is unspecified, convection due to the effects of thermal expansion and buoyancy can be assumed. Convection may also take place in soft solids or mixtures where particles can flow.
Convective flow may be transient (such as when a multiphase mixture of oil and water separates) or steady state (see Convection cell). The convection may be due to gravitational, electromagnetic or fictitious body forces. Heat transfer by natural convection plays a role in the structure of Earth's atmosphere, its oceans, and its mantle. Discrete convective cells in the atmosphere can be identified by clouds, with stronger convection resulting in thunderstorms. Natural convection also plays a role in stellar physics. Convection is often categorised or described by the main effect causing the convective flow, e.g. Thermal convection.

Convection cannot take place in most solids because neither bulk current flows nor significant diffusion of matter can take place.

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  1. M

    Heat Transfer Coefficients: Free and Forced Convection

    Hi all. I'm currently working on a problem where I have to determine individual and overall heat transfer coefficients for a vertical cylinder with water flowing on the inside and steam on the outside (parallel flow), studying the cases of free and forced convection. I only have four...
  2. R

    Heat transfer through AL shield by radiation & convection

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  3. J

    Thermal-expansion coefficients, convection as function of T

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  4. MrGianmarcoD

    Earth's Energy balance including a convective component

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  5. G

    Heat Transfer in glass pane windows

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  6. V

    Convection: Realising a Trivial Thing?

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  7. E

    Overall heat transfer coefficient for free convection exchanger

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  8. B

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  9. E

    Thermal Resistance due to Convection Heat Transfer

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  10. D

    Heat Loss Through a Box with a hole in it

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  11. D

    What is the temperature of an iron bar after 1 hour of convection heating?

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  12. F

    Increase temperature of liquid in a box without heat convection or conduction

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  13. S

    Conduction and convection- processes understanding

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  14. Y

    Thermal Physics: Cooling by both Conduction & Convection

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  15. N

    Stability condition for solving convection equation by FDM

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  16. K

    Explain convection heat transfer using kinetic theory

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  17. gauss44

    Home Improvement Project & PV=nRT

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  18. E

    How Does a Hot Molecule Move in a Convection Current?

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  19. H

    Derivation of "heat" equation w/ diffusion and convection

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  20. T

    Need explanation on Chracteristic Length in heat convection

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  21. D

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  22. C

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  23. U

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  24. O

    Could Convection Current power a stirring device in a saucepan

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  25. M

    Finding thermal conductivity with conduction and convection.

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  26. L

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  27. C

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  28. Maxo

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  29. M

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  30. N

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  31. W

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  32. T

    Why Does the Convection Heat Transfer Coefficient Vary with Temperature?

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  33. K

    Is there a general equation for convection of a fin's side surface

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  34. Z

    Direction of wind for forced convection

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  35. J

    Convection Currents Explained - No Pressure Difference

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  36. M

    Optimal fin spacing for natural convection when Nu = 1

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  37. T

    Finding the convection of a node in a hot pipe

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  38. C

    Mathematical Model for Convection Current

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  39. C

    Mathematical Model for Convection Currents

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  40. M

    Question combined mode radiation and convection ?

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  41. OdinAF

    What Is the Convection Coefficient Between Aluminum 4032 and Steel?

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  42. D

    Convection ; good conductor & bad conductor difference?

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  43. Z

    How to Calculate Mass Flow in a Torus Due to Temperature Differences?

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  44. L

    Convection and Radiation in an Electrically Heated Cylinder

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  45. F

    Thermodynamics: Convection and Industrial PC Heatsinks

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  46. S

    Rayleigh number for vertical cylinder with free convection

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  47. A

    Typical value free air convection heat transfer coefficient

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  48. H

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  49. J

    Can Rayleigh–Bénard Convection Be Observed at Home?

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  50. A

    Link between pressure and convection heat transfer ?

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