Rayleigh Number Calculator

✖Grashof Number approximates the ratio of the buoyancy to viscous force acting on a fluid.ⓘ Grashof Number [G]			+10% -10%
✖Prandtl Number (Pr) or Prandtl group is a dimensionless number, named after the German physicist Ludwig Prandtl, defined as the ratio of momentum diffusivity to thermal diffusivity.ⓘ Prandtl Number [Pr]			+10% -10%

✖Rayleigh Number(t) is a dimensionless parameter that is a measure of the instability of a layer of fluid due to differences of temperature and density at the top and bottom.ⓘ Rayleigh Number [Ra_c]

⎘ Copy

👎

Formula

LaTeX

Reset

👍

Download Chemical Engineering Formula PDF PDF Image

Rayleigh Number Solution

STEP 0: Pre-Calculation Summary

Formula Used

Rayleigh Number(t) = Grashof Number*Prandtl Number
Ra_c = G*Pr
This formula uses 3 Variables

Variables Used

Rayleigh Number(t) - Rayleigh Number(t) is a dimensionless parameter that is a measure of the instability of a layer of fluid due to differences of temperature and density at the top and bottom.
Grashof Number - Grashof Number approximates the ratio of the buoyancy to viscous force acting on a fluid.
Prandtl Number - Prandtl Number (Pr) or Prandtl group is a dimensionless number, named after the German physicist Ludwig Prandtl, defined as the ratio of momentum diffusivity to thermal diffusivity.

STEP 1: Convert Input(s) to Base Unit

Grashof Number: 0.87 --> No Conversion Required
Prandtl Number: 0.7 --> No Conversion Required

STEP 2: Evaluate Formula

Substituting Input Values in Formula

Ra_c = G*Pr --> 0.87*0.7

Evaluating ... ...

Ra_c = 0.609

STEP 3: Convert Result to Output's Unit

0.609 --> No Conversion Required

FINAL ANSWER

0.609 <-- Rayleigh Number(t)

(Calculation completed in 00.004 seconds)

You are here -

Home » Engineering » Chemical Engineering » Fluid Dynamics » Dimensionless Numbers » Rayleigh Number

Credits

Created by Nishan Poojary

Shri Madhwa Vadiraja Institute of Technology and Management (SMVITM), Udupi

Nishan Poojary has created this Calculator and 500+ more calculators!

Verified by Rajat Vishwakarma

University Institute of Technology RGPV (UIT - RGPV), Bhopal

Rajat Vishwakarma has verified this Calculator and 400+ more calculators!

< Dimensionless Numbers Calculators

Archimedes Number

LaTeX Go Archimedes Number = ([g]*Characteristic Length^(3)*Density of Fluid*(Density of Body-Density of Fluid))/(Dynamic Viscosity)^(2)

Reynolds Number

LaTeX Go Reynolds Number = (Density of Liquid*Fluid Velocity*Diameter of Pipe)/Dynamic Viscosity

Euler Number using Fluid Velocity

LaTeX Go Euler Number = Fluid Velocity/(sqrt(Change in Pressure/Density of Fluid))

Weber Number

LaTeX Go Weber Number = ((Density*(Velocity of Fluid^2)*Length)/Surface Tension)

< Rayleigh and Reynolds Number Calculators

Rayleigh number based on turbulence for annular space between concentric cylinders

LaTeX Go Rayleigh Number(t) = ((((ln(Outer Diameter/Inner Diameter))^4)*(Rayleigh Number))/((Length^3)*((Inner Diameter^-0.6)+(Outer Diameter^-0.6))^5))

Rayleigh number based on length for annular space between concentric cylinders

LaTeX Go Rayleigh Number = Rayleigh Number(t)/((((ln(Outer Diameter/Inner Diameter))^4))/((Length^3)*((Inner Diameter^-0.6)+(Outer Diameter^-0.6))^5))

Rayleigh number based on turbulence for concentric spheres

LaTeX Go Rayleigh Number(t) = ((Length*Rayleigh Number)/(((Inside Diameter*Outside Diameter)^4)*(((Inside Diameter^-1.4)+(Outside Diameter^-1.4))^5)))^0.25

Reynolds Number given Graetz Number

LaTeX Go Reynolds Number Based on Length = Graetz Number*Length/(Prandtl Number*Diameter)

Rayleigh Number Formula

LaTeX Go

Rayleigh Number(t) = Grashof Number*Prandtl Number
Ra_c = G*Pr

What is Convection?

Convection is the process of heat transfer by the bulk movement of molecules within fluids such as gases and liquids. The initial heat transfer between the object and the fluid takes place through conduction, but the bulk heat transfer happens due to the motion of the fluid.

How to Calculate Rayleigh Number?

Rayleigh Number calculator uses Rayleigh Number(t) = Grashof Number*Prandtl Number to calculate the Rayleigh Number(t), The Rayleigh Number formula is defined as a dimensionless parameter that is a measure of the instability of a layer of fluid due to differences of temperature and density at the top and bottom. Rayleigh Number(t) is denoted by Ra_c symbol.

How to calculate Rayleigh Number using this online calculator? To use this online calculator for Rayleigh Number, enter Grashof Number (G) & Prandtl Number (Pr) and hit the calculate button. Here is how the Rayleigh Number calculation can be explained with given input values -> 0.609 = 0.87*0.7.

FAQ

What is Rayleigh Number?

The Rayleigh Number formula is defined as a dimensionless parameter that is a measure of the instability of a layer of fluid due to differences of temperature and density at the top and bottom and is represented as Ra_c = G*Pr or Rayleigh Number(t) = Grashof Number*Prandtl Number. Grashof Number approximates the ratio of the buoyancy to viscous force acting on a fluid & Prandtl Number (Pr) or Prandtl group is a dimensionless number, named after the German physicist Ludwig Prandtl, defined as the ratio of momentum diffusivity to thermal diffusivity.

How to calculate Rayleigh Number?

The Rayleigh Number formula is defined as a dimensionless parameter that is a measure of the instability of a layer of fluid due to differences of temperature and density at the top and bottom is calculated using Rayleigh Number(t) = Grashof Number*Prandtl Number. To calculate Rayleigh Number, you need Grashof Number (G) & Prandtl Number (Pr). With our tool, you need to enter the respective value for Grashof Number & Prandtl Number and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.

How many ways are there to calculate Rayleigh Number(t)?

In this formula, Rayleigh Number(t) uses Grashof Number & Prandtl Number. We can use 2 other way(s) to calculate the same, which is/are as follows -

Rayleigh Number(t) = ((((ln(Outer Diameter/Inner Diameter))^4)*(Rayleigh Number))/((Length^3)*((Inner Diameter^-0.6)+(Outer Diameter^-0.6))^5))
Rayleigh Number(t) = ((Length*Rayleigh Number)/(((Inside Diameter*Outside Diameter)^4)*(((Inside Diameter^-1.4)+(Outside Diameter^-1.4))^5)))^0.25

Home

FREE PDFs

🔍 Search