Fx Copy
LaTeX Copy
Heat Flow Rate is the amount of heat that is transferred per unit of time in some material, usually measured in watt. Heat is the flow of thermal energy driven by thermal non-equilibrium. Check FAQs
Q=Ti-Toln(r2r1)2πklcyl
Q - Heat Flow Rate?Ti - Inner Surface Temperature?To - Outer Surface Temperature?r2 - Radius of 2nd Cylinder?r1 - Radius of 1st Cylinder?k - Thermal Conductivity?lcyl - Length of Cylinder?π - Archimedes' constant?

Heat Flow Rate through Cylindrical Wall Example

With values
With units
Only example

Here is how the Heat Flow Rate through Cylindrical Wall equation looks like with Values.

Here is how the Heat Flow Rate through Cylindrical Wall equation looks like with Units.

Here is how the Heat Flow Rate through Cylindrical Wall equation looks like.

47.239Edit=305Edit-300Editln(12Edit0.8Edit)23.141610.18Edit0.4Edit
You are here -
HomeIcon Home » Category Physics » Category Mechanical » Category Heat and Mass Transfer » fx Heat Flow Rate through Cylindrical Wall

Heat Flow Rate through Cylindrical Wall Solution

Follow our step by step solution on how to calculate Heat Flow Rate through Cylindrical Wall?

FIRST Step Consider the formula
Q=Ti-Toln(r2r1)2πklcyl
Next Step Substitute values of Variables
Q=305K-300Kln(12m0.8m)2π10.18W/(m*K)0.4m
Next Step Substitute values of Constants
Q=305K-300Kln(12m0.8m)23.141610.18W/(m*K)0.4m
Next Step Prepare to Evaluate
Q=305-300ln(120.8)23.141610.180.4
Next Step Evaluate
Q=47.2390256288857W
LAST Step Rounding Answer
Q=47.239W

Heat Flow Rate through Cylindrical Wall Formula Elements

Variables
Constants
Functions
Heat Flow Rate
Heat Flow Rate is the amount of heat that is transferred per unit of time in some material, usually measured in watt. Heat is the flow of thermal energy driven by thermal non-equilibrium.
Symbol: Q
Measurement: PowerUnit: W
Note: Value can be positive or negative.
Inner Surface Temperature
Inner Surface Temperature is the temperature at the inner surface of the wall either plane wall or cylindrical wall or spherical wall, etc.
Symbol: Ti
Measurement: TemperatureUnit: K
Note: Value can be positive or negative.
Outer Surface Temperature
Outer surface temperature is the temperature at the outer surface of the wall (either plane wall or cylindrical wall or spherical wall, etc).
Symbol: To
Measurement: TemperatureUnit: K
Note: Value can be positive or negative.
Radius of 2nd Cylinder
Radius of 2nd Cylinder is the distance from the center of the concentric circles to any point on the Second concentric circle or radius of the third circle.
Symbol: r2
Measurement: LengthUnit: m
Note: Value can be positive or negative.
Radius of 1st Cylinder
Radius of 1st Cylinder is the distance from the center of the concentric circles to any point on the first/smallest concentric circle for the first cylinder in the series.
Symbol: r1
Measurement: LengthUnit: m
Note: Value can be positive or negative.
Thermal Conductivity
Thermal Conductivity is rate of heat passes through specified material, expressed as amount of heat flows per unit time through a unit area with a temperature gradient of one degree per unit distance.
Symbol: k
Measurement: Thermal ConductivityUnit: W/(m*K)
Note: Value should be greater than 0.
Length of Cylinder
Length of Cylinder is the vertical height of the Cylinder.
Symbol: lcyl
Measurement: LengthUnit: m
Note: Value should be greater than 0.
Archimedes' constant
Archimedes' constant is a mathematical constant that represents the ratio of the circumference of a circle to its diameter.
Symbol: π
Value: 3.14159265358979323846264338327950288
ln
The natural logarithm, also known as the logarithm to the base e, is the inverse function of the natural exponential function.
Syntax: ln(Number)

Other Formulas to find Heat Flow Rate

​Go Heat Flow Rate through Cylindrical Composite Wall of 2 Layers
Q=Ti-Toln(r2r1)2πk1lcyl+ln(r3r2)2πk2lcyl
​Go Heat Flow Rate through Cylindrical Composite Wall of 3 Layers
Q=Ti-Toln(r2r1)2πk1lcyl+ln(r3r2)2πk2lcyl+ln(r4r3)2πk3lcyl

Other formulas in Conduction in Cylinder category

​Go Total Thermal Resistance of 2 Cylindrical Resistances Connected in Series
Rth=ln(r2r1)2πk1lcyl+ln(r3r2)2πk2lcyl
​Go Total Thermal Resistance of 3 Cylindrical Resistances Connected in Series
Rth=ln(r2r1)2πk1lcyl+ln(r3r2)2πk2lcyl+ln(r4r3)2πk3lcyl

How to Evaluate Heat Flow Rate through Cylindrical Wall?

Heat Flow Rate through Cylindrical Wall evaluator uses Heat Flow Rate = (Inner Surface Temperature-Outer Surface Temperature)/((ln(Radius of 2nd Cylinder/Radius of 1st Cylinder))/(2*pi*Thermal Conductivity*Length of Cylinder)) to evaluate the Heat Flow Rate, The Heat flow rate through cylindrical wall formula is defined as the rate of heat flow through a cylindrical wall in the radial direction when inner and outer surface temperatures, length of the cylinder, inner and outer radii and thermal conductivity are known. Heat Flow Rate is denoted by Q symbol.

How to evaluate Heat Flow Rate through Cylindrical Wall using this online evaluator? To use this online evaluator for Heat Flow Rate through Cylindrical Wall, enter Inner Surface Temperature (Ti), Outer Surface Temperature (To), Radius of 2nd Cylinder (r2), Radius of 1st Cylinder (r1), Thermal Conductivity (k) & Length of Cylinder (lcyl) and hit the calculate button.

FAQs on Heat Flow Rate through Cylindrical Wall

What is the formula to find Heat Flow Rate through Cylindrical Wall?
The formula of Heat Flow Rate through Cylindrical Wall is expressed as Heat Flow Rate = (Inner Surface Temperature-Outer Surface Temperature)/((ln(Radius of 2nd Cylinder/Radius of 1st Cylinder))/(2*pi*Thermal Conductivity*Length of Cylinder)). Here is an example- 8.266829 = (305-300)/((ln(12/0.8))/(2*pi*10.18*0.4)).
How to calculate Heat Flow Rate through Cylindrical Wall?
With Inner Surface Temperature (Ti), Outer Surface Temperature (To), Radius of 2nd Cylinder (r2), Radius of 1st Cylinder (r1), Thermal Conductivity (k) & Length of Cylinder (lcyl) we can find Heat Flow Rate through Cylindrical Wall using the formula - Heat Flow Rate = (Inner Surface Temperature-Outer Surface Temperature)/((ln(Radius of 2nd Cylinder/Radius of 1st Cylinder))/(2*pi*Thermal Conductivity*Length of Cylinder)). This formula also uses Archimedes' constant and Natural Logarithm (ln) function(s).
What are the other ways to Calculate Heat Flow Rate?
Here are the different ways to Calculate Heat Flow Rate-
  • Heat Flow Rate=(Inner Surface Temperature-Outer Surface Temperature)/((ln(Radius of 2nd Cylinder/Radius of 1st Cylinder))/(2*pi*Thermal Conductivity 1*Length of Cylinder)+(ln(Radius of 3rd Cylinder/Radius of 2nd Cylinder))/(2*pi*Thermal Conductivity 2*Length of Cylinder))OpenImg
  • Heat Flow Rate=(Inner Surface Temperature-Outer Surface Temperature)/((ln(Radius of 2nd Cylinder/Radius of 1st Cylinder))/(2*pi*Thermal Conductivity 1*Length of Cylinder)+(ln(Radius of 3rd Cylinder/Radius of 2nd Cylinder))/(2*pi*Thermal Conductivity 2*Length of Cylinder)+(ln(Radius of 4th Cylinder/Radius of 3rd Cylinder))/(2*pi*Thermal Conductivity 3*Length of Cylinder))OpenImg
Can the Heat Flow Rate through Cylindrical Wall be negative?
Yes, the Heat Flow Rate through Cylindrical Wall, measured in Power can be negative.
Which unit is used to measure Heat Flow Rate through Cylindrical Wall?
Heat Flow Rate through Cylindrical Wall is usually measured using the Watt[W] for Power. Kilowatt[W], Milliwatt[W], Microwatt[W] are the few other units in which Heat Flow Rate through Cylindrical Wall can be measured.
Copied!