Discovered by Lord Rayleigh in 1885, this equation has found widespread applications in diverse fields, from seismology and geophysics to materials science and non-destructive testing. This comprehensive guide aims to provide a deep understanding of the Rayleigh Equation, its underlying principles, and its practical uses.
Rayleigh Wave Calculator
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Material Database
Rayleigh equation for separation of chemicals:
For the batch distillation process where a fixed quantity of feed is charged to the distillation column and the separation of volatile products is done by supplying heat through the still or reboiler. As the boiling point of the liquid is reached a portion of the liquid starts to vaporize to the top of the column and is directed to the condenser, the vapor leaving the column is always in equilibrium with the liquid in the bottom of the column, thus a material balance equation is produced by Rayleigh called Rayleigh Equation which provides standard equilibrium data. For research and calculation of process conditions, this data is used to generate design equations. To determine the composition change with time Rayleigh equation is used and can be derived as:
Consider a liquid mixture of ‘Ao’ moles fed to the batch column. Let ‘A’ moles of liquid remain in the bottom of the column. At a given instant of time let y and x be the composition of vapor and liquid.
Material Balance:Total moles of component B left in the vessel: xA
Let dA be the amount of liquid vaporized than the mole of component B varies is: ydA or dAB
: dAB = Adx+xdA
By integration to the limits of initial and final concentrations, we produce a Rayleigh Equations:
Rayleigh Equation Calculator (Batch Distillation)
This calculator provides a practical tool for understanding and applying the Rayleigh equation in batch distillation with a combination of the analytical solution and Newton-Raphson method providing a fast and accurate result.