enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Pulsatile flow - Wikipedia

    en.wikipedia.org/wiki/Pulsatile_flow

    is the angular frequency of the first harmonic of a Fourier series of an oscillatory pressure gradient, n: are the natural numbers, P' n: is the pressure gradient magnitude for the frequency nω, ρ: is the fluid density, μ: is the dynamic viscosity, R: is the pipe radius, J 0 (·) is the Bessel function of first kind and order zero, i: is the ...

  3. Optical pumping - Wikipedia

    en.wikipedia.org/wiki/Optical_pumping

    Optical pumping is a process in which light is used to raise (or "pump") electrons from a lower energy level in an atom or molecule to a higher one. It is commonly used in laser construction to pump the active laser medium so as to achieve population inversion. The technique was developed by the 1966 Nobel Prize winner Alfred Kastler in the ...

  4. List of equations in fluid mechanics - Wikipedia

    en.wikipedia.org/wiki/List_of_equations_in_fluid...

    Flux F through a surface, dS is the differential vector area element, n is the unit normal to the surface. Left: No flux passes in the surface, the maximum amount flows normal to the surface.

  5. Fluid dynamics - Wikipedia

    en.wikipedia.org/wiki/Fluid_dynamics

    In physics, physical chemistry 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 water and other liquids in motion).

  6. Phase conjugation - Wikipedia

    en.wikipedia.org/wiki/Phase_conjugation

    Then, a second pump wave reads the recorded signal and produces the conjugate wave. All those waves have the same frequency. In parametric pumping, the parameters of the medium are modulated by the pump wave at double frequency. The interaction of this perturbation with the incident wave will produce the conjugate wave.

  7. Centrifugal pump - Wikipedia

    en.wikipedia.org/wiki/Centrifugal_pump

    Warman centrifugal pump in a coal preparation plant application A pair of centrifugal pumps for circulating hot water within a hydronic heating system. Centrifugal pumps are used to transport fluids by the conversion of rotational kinetic energy to the hydrodynamic energy of the fluid flow. The rotational energy typically comes from an engine ...

  8. Secondary flow - Wikipedia

    en.wikipedia.org/wiki/Secondary_flow

    Consequently, near the center of the tornado or dust devil the air pressure is low. There is a pressure gradient toward the center of the vortex. This gradient, coupled with the slower speed of the air near the earth's surface, causes a secondary flow toward the center of the tornado or dust devil, rather than in a purely circular pattern.

  9. Gradient - Wikipedia

    en.wikipedia.org/wiki/Gradient

    For example, the gradient of the function (,,) = + ⁡ is (,,) = + ⁡ (). or (,,) = [⁡]. In some applications it is customary to represent the gradient as a row vector or column vector of its components in a rectangular coordinate system; this article follows the convention of the gradient being a column vector, while the derivative is a row ...