What is Compressible: Definition and 79 Discussions

In thermodynamics and fluid mechanics, the compressibility (also known as the coefficient of compressibility or, if the temperature is held constant, the isothermal compressibility) is a measure of the relative volume change of a fluid or solid as a response to a pressure (or mean stress) change. In its simple form, the compressibility



κ


{\displaystyle \kappa }
(denoted β in some fields) may be expressed as




κ
=



1
V






V



p





{\displaystyle \kappa =-{\frac {1}{V}}{\frac {\partial V}{\partial p}}}
,where V is volume and p is pressure. The choice to define compressibility as the negative of the fraction makes compressibility positive in the (usual) case that an increase in pressure induces a reduction in volume. The reciprocal of compressibility at fixed temperature is called the isothermal bulk modulus.

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  1. R

    Compressible Flow Question

    Hi I was wondering, if a flow is compressible, then does that mean that if the inlet and exit of the control volume (same C.S. area) have different densities, would that mean that the temperature and/or pressure of the exit be different than at the inlet (assuming ideal gas)? If this were...
  2. F

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  3. M

    Heat Equation for Compressible Fluids: Valid or Not?

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  4. U

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  5. D

    Isothermal compressible flow in horizontal pipe

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  6. K

    Exploring Subsonic, Compressible Flow in Curved Ducts

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  7. E

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  8. G

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  9. T

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  10. B

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  11. T

    Hydraulic press and compressible fluids

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  12. K

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  13. J

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  14. K

    Energy loss in compressible flow

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  15. J

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  16. B

    What soft compressible materials safely work with wiring

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  17. A

    Compressible Flow: Flow in nozzles

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  18. C

    Diving Board Stress Points: Shear, Compressible, & Normal

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  19. J

    Finding Outlet Diameter for Compressible Fluid Flow

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  20. J

    Calculating Head Loss from Enlargement in Compressible Fluid

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  21. M

    Difference between compressible and incompressible flow

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  22. D

    What are some real-world examples of compressible fluid mechanics in action?

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  23. V

    Compressible or imcompressible?

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  24. A

    Deriving Conservation of Mass & Momentum for an Inviscid Compressible Gas

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  25. L

    Bernoulli's Principle on Unsteady State and Compressible Fluid

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  26. C

    Can 25 PSI Methane Flow Through a 3/8 Pipe Meet a 392,000 BTU/hr Demand?

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  27. M

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  28. I

    Compressible Fluid Thermodynamics

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  29. S

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