How to Calculate and Solve for Heat Flux | Thermal Properties
Last Updated on July 25, 2022
The heat flux is illustrated by the image below.
To compute for heat flux, two essential parameters are needed and these parameters are Thermal Conductivity (K) and Change in Temperature per Change in Distance per Heat Flow (dT/dx).
The formula for calculating heat flux:
q = -K (dT/dx)
Where:
q = Heat Flux (K)
K = Thermal Conductivity
dT/dx = Change in Temperature per Change in Distance per Heat Flow
Given an example;
Find the heat flux when the thermal conductivity is 22 and the change in temperature per change in distance per heat flow is 10.
This implies that;
K = Thermal Conductivity = 22
dT/dx = Change in Temperature per Change in Distance per Heat Flow = 10
q = -K (dT/dx)
q = -(22) (10)
q = -220
Therefore, the heat flux is -220 W.
Calculating the Thermal Conductivity when the Heat Flux and the Change in Temperature per Change in Distance per Heat Flow is Given.
K = – q / dT/dx
Where:
K = Thermal Conductivity
q = Heat Flux (K)
dT/dx = Change in Temperature per Change in Distance per Heat Flow
Let’s solve an example;
Find the thermal conductivity when the heat flux is 42 and the change in temperature per change in distance per heat flow is 8.
This implies that;
q = Heat Flux (K) = 42
dT/dx = Change in Temperature per Change in Distance per Heat Flow = 8
K = – q / dT/dx
K = – 42 / 8
K = -6
Therefore, the thermal conductivity is -6.
Calculating the Change in Temperature per Change in Distance per Heat Flow when the Thermal Conductivity and the Heat Flux is Given.
dT/dx = – q / K
Where:
dT/dx = Change in Temperature per Change in Distance per Heat Flow
q = Heat Flux (K)
K = Thermal Conductivity
Let’s solve an example;
Find the change in temperature per change in distance per heat flow when the heat flux is 20 and the thermal conductivity is 2.
This implies that;
q = Heat Flux (K) = 20
K = Thermal Conductivity = 2
dT/dx = – q / K
dT/dx = – 20 / 2
dT/dx = – 10
Therefore, the change in temperature per change in distance per heat flow is -10.
Nickzom Calculator – The Calculator Encyclopedia is capable of calculating the heat flux.
To get the answer and workings of the heat flux using the Nickzom Calculator – The Calculator Encyclopedia. First, you need to obtain the app.
You can get this app via any of these means:
Web – https://www.nickzom.org/calculator-plus
To get access to the professional version via web, you need to register and subscribe to have utter access to all functionalities.
You can also try the demo version via https://www.nickzom.org/calculator
Android (Paid) – https://play.google.com/store/apps/details?id=org.nickzom.nickzomcalculator
Android (Free) – https://play.google.com/store/apps/details?id=com.nickzom.nickzomcalculator
Apple (Paid) – https://itunes.apple.com/us/app/nickzom-calculator/id1331162702?mt=8
Once, you have obtained the calculator encyclopedia app, proceed to the Calculator Map, then click on Materials and Metallurgical under Engineering.
Now, Click on Thermal Properities under Materials and Metallurgical
Now, Click on Heat Flux under Thermal Properities
The screenshot below displays the page or activity to enter your values, to get the answer for the heat flux according to the respective parameter which is the Thermal Conductivity (K) and Change in Temperature per Change in Distance per Heat Flow (dT/dx).
Now, enter the values appropriately and accordingly for the parameters as required by the Thermal Conductivity (K) is 22 and Change in Temperature per Change in Distance per Heat Flow (dT/dx) is 10.
Finally, Click on Calculate
As you can see from the screenshot above, Nickzom Calculator– The Calculator Encyclopedia solves for the heat flux and presents the formula, workings and steps too.