What is the significance of Graetz number?

What is the significance of Graetz number?

This number is useful in determining the thermally developing flow entrance length in ducts. A Graetz number of approximately 1000 or less is the point at which flow would be considered thermally fully developed.

What is the significance of Schmidt number?

Schmidt number (Sc) is a dimensionless number defined as the ratio of momentum diffusivity (kinematic viscosity) and mass diffusivity, and is used to characterize fluid flows in which there are simultaneous momentum and mass diffusion convection processes.

How do I find my Sherwood number?

Formula

1. Sherwood Number : Sh = kl/D.
2. Mass Transfer Coefficient : k = ShD/L.
3. Characteristic Length : L = ShD/k.
4. Diffusion Coefficient : D = kl/Sh.
5. Where, Sh = Sherwood Number, k = Mass Transfer Coefficient, L = Characteristic Length, D = Diffusion Coefficient.

How do you define Stanton number for mass transfer?

The Stanton number, St, is a dimensionless number that measures the ratio of heat transferred into a fluid to the thermal capacity of fluid. The Stanton number is named after Thomas Stanton (engineer) (1865–1931). It is used to characterize heat transfer in forced convection flows.

What is Alpha in Fourier number?

α = Thermal Diffusivity, t = Characteristic Time, L = Characteristic Length.

What is Graetz problem?

The Graetz problem is a fundamental tube flow problem that couples fluid flow with heat and/or mass transfer. It is critically important in dealing with chemical reactors, heat exchangers, blood flow and a host of other phenomena.

What is the physical significance of Lewis number?

The Lewis number is defined as the ratio of thermal diffusivity and mass diffusivity. It is used to characterize fluid flows where there is simultaneous heat and mass transfer. The Lewis number is therefore a measure of the relative thermal and concentration boundary layer thicknesses.

What is the physical significance of the Schmidt number what is the heat transfer equivalent of this number What does SC 1 signify?

The Schmidt number corresponds to the Prandtl number in heat transfer. A Schmidt number of unity indicates that momentum and mass transfer by diffusion are comparable, and velocity and concentration boundary layers almost coincide with each other.

How is Schmidt number calculated?

The Schmidt number (Sc) is the ratio of the kinematic viscosity to the molecular diffusion coefficient, i.e., Sc= v/Dm.

What is kC in mass transfer?

The convective mass transfer coefficient kC is a function of geometry of the system and the velocity and properties of the fluid similar to the heat transfer coefficient, h. 2.3 Significant Parameters in Convective Mass Transfer. Dimensionless parameters are often used to correlate convective transfer data.

What is Stanton number formula?

The Stanton number is a dimensionless number that measures the ratio of heat transferred into a fluid to the thermal capacity of fluid. The Stanton number equals the heat transfer coefficient divided by the product of the specific heat capacity, haracteristic speed and the mass density.

What is Peclet number mention its significance in CFD?

Peclet number, or officially known as Péclet number, is a dimensionless number that represents the ratio of advection and diffusion caused by heat transfer. The greater Péclet number becomes, the more convection effects act on thermal transfer.

What is the meaning of Sherwood number?

The Sherwood number (Sh) (also called the mass transfer Nusselt number) is a dimensionless number used in mass-transfer operation. It represents the ratio of the convective mass transfer to the rate of diffusive mass transport, and is named in honor of Thomas Kilgore Sherwood. It is defined as follows.

What is the Sherwood number (SH) for polarization?

Concentration polarization has been studied using the Sherwood number (Sh). Sh is defined as the ratio of convective to diffusive mass transfer. It is a dimensionless number and the mass transfer equivalent of Nu. The overall mass transfer coefficient (K) can be obtained from the definition of Sh.

What is the Sherwood number in gas phase?

Gas phase mass transfer coefficient, mol/ (m 2 .s.mole fraction) The Sherwood number is a dimensionless number named in honour of Thomas Kilgore Sherwood and describes the ratio of convective mass transfer to the rate of diffusive mass transfer. It is the mass transfer equivalent of the Nusselt Number and is formulated as follows:

What is the difference between Nusselt and Sherwood numbers?

The Sherwood number is defined as the ratio of the convective mass transfer to the mass diffusivity. The Nusselt and Sherwood numbers represent the effectiveness of heat and mass convection at the surface. The Sherwood number is to the concentration boundary layer what the Nusselt number is to the thermal boundary layer.