Units of quantities

1. Kinematic viscosity= Dynamic viscosity\\ Density

unit: m^2* S^-1

2. Dynamic viscosity= Shear stress* velocity gradient

unit: kg*( mS)^-1

3. Peclet number= It is the product of Reynold\'s number and Prandtl number,It can also be defined as the ratio of thermal energy convected within the fluid to the ratio of thermal energy conducted within the fluid since it is a dimensionless number it has no units.

4. Nusselt number= It is the ratio of convective to conductive heat transfer at the boundary. It is also a dimensionless number which is also a function of Reynold\'s number and Prandtl number.

5. Momentum flux= It is the transport of momentum in the direction perpendicular to the direction of fluid flow. It has the same unit as pressure

Unit: kg *m*s^-2

6. It states that the time rate of heat transfer through a material is proportional to the negative gradient in the temperature and to the area at right angles to the gradient through which the heat flows.

7. Fick\'s first law states that the flux goes from regions of high concentration to the regions of low concentration with a magnitude proportional to the concentration gradient.(concentration in mol/ m^3)

Fick\'s second law states that the rate of diffusion is a function of the second partial derivative of concentration w.r.t x(position) or the first partial derivative of diffusion gradient w.r.t x.

8. The tangential frictional force exerted by a fluid on a wall / surface when the find flows against it.

It is the product of dynamic viscosity and the partial derivative of velocity w.r.t distance from the wall

Unit: kg*m*s^-1

9. It is a physical quantity which describes in what direction and at what rate temperature changes more rapidly around a point.

Unit: K* m^-1

10. It defines the volume density of outward flux of velocity vectors in the given area. For expanding air divergence is positive.