The Lewis number (Le) is a dimensionless number defined as the ratio of thermal diffusivity to mass diffusivity. It is used to characterize fluid flows where there is simultaneous heat and mass transfer.
Lewis number is appear in dimensionless concentration equation.
The Lewis number (Le) is a dimensionless number defined as the ratio of thermal diffusivity to mass diffusivity. It is used to characterize fluid flows where there is simultaneous heat and mass transfer.
The Lewis number ( Le ) is a dimensionless number defined as the ratio of thermal diffusivity to mass diffusivity. It is used to characterize fluid flows where there is simultaneous heat and mass transfer.
where is the thermal diffusivity and the mass diffusivity, the thermal conductivity , the density,
the mixture-averaged diffusion coefficient, and
the specific heat capacity at constant pressure.
The Lewis number can also be expressed in terms of the Prandtl number and the Schmidt number :
....hence, and in the context of a boundary layer flow, Le>1 means that heat diffuses more easily than solute does and therefore the thermal boundary layer thickness will be greater than the solutal boundary layer thickness.
Lewis number (Le) is a dimensionless number defined as the ratio of thermal diffusivity to mass diffusivity. it appears when we want to characterize fluid flows where there is simultaneous heat and mass transfer. it changes according to the nature of mixture fluid. for example Le is around of 1 for gases flow and Le>>1 for liquids flow.
you can refer to thermopedia or wikipedia for the definition of
The Lewis Number (Le) is defined as the ratio of the Schmidt Number (Sc) and the Prandtl Number (Pr). The Lewis Number is also the ratio of thermal diffusivity and molecular diffusivity as is found from the definitions of Schmidt and Prandtl Number
It seems to me that this discussion is complete, unless there is some novelty which I am unaware of!
Lewis Number (Le) is defined as the ratio of the Schmidt Number (Sc) and the Prandtl Number (Pr).
The Lewis number (Le) is a dimensionless number defined as the ratio of thermal diffusivity to mass diffusivity. It is used to characterize fluid flows where there is simultaneous heat and mass transfer.
The ratio of thermal diffusivity to mass diffusivity and is a dimensionless number
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