How to Calculate and Solve for Heat Flux | Solidification of Metals

Last Updated on September 14, 2021

The image above represents heat flux.

To compute for heat flux, three essential parameters are needed and these parameters are Thermal Conductivity (K), Density (ρ) and Heat Capacity at Constant Pressure (c_p).

The formula for calculating heat flux:

q = ^K / _ρcp

Where:

q = Heat Flux
K = Thermal Conductivity
ρ = Density
c_p = Heat Capacity at Constant Pressure

Let’s solve an example;
Find the heat flux when the thermal conductivity is 21, the density is 12 and the heat capacity at constant pressure is 24.

This implies that;’

K = Thermal Conductivity = 21
ρ = Density = 12
c_p = Heat Capacity at Constant Pressure = 24

q = ^K / _ρcp
q = ²¹ / _(12)(24)
q = ²¹ / ₂₈₈
q = 0.0729

Therefore, the heat flux is 0.0729 W.

Calculating the Thermal Conductivity when the Heat Flux, the Density and the Heat Capacity at Constant Pressure is Given.

K = q (ρ c_p)

Where:

K = Thermal Conductivity
q = Heat Flux
ρ = Density
c_p = Heat Capacity at Constant Pressure

Let’s solve an example;
Find the thermal conductivity when the heat flux is 15, the density is 10 and the heat capacity at constant pressure is 14.

This implies that;

q = Heat Flux = 15
ρ = Density = 10
c_p = Heat Capacity at Constant Pressure = 14

K = q (ρ c_p)
K = 15 (10 x 14)
K = 15 (140)
K = 2100

Therefore, the thermal conductivity is 2100.

Calculating the Density when the Heat Flux, the Thermal Conductivity and the Heat Capacity at Constant Pressure is Given.

ρ = ^K / _{q x cp}

Where:

ρ = Density
q = Heat Flux
K = Thermal Conductivity
c_p = Heat Capacity at Constant Pressure

Let’s solve an example;
Find the density when the heat flux is 18, the thermal conductivity is 12 and the heat capacity at constant pressure is 4.

This implies that;

q = Heat Flux = 18
K = Thermal Conductivity = 12
c_p = Heat Capacity at Constant Pressure = 4

ρ = ^K / _{q x cp}
ρ = ¹² / _{18 x 4}
ρ = ¹² / ₇₂
ρ = 0.167

Therefore, the density is 0.167.

Calculating the Heat Capacity at Constant Pressure when the Heat Flux, the Thermal Conductivity and the Density is Given.

c_p = ^K / _{q x ρ}

Where:

c_p = Heat Capacity at Constant Pressure
q = Heat Flux
K = Thermal Conductivity
ρ = Density

Let’s solve an example;
Find the heat capacity at constant pressure when the heat flux is 10, the thermal conductivity is 20 and the density is 6.

This implies that;

q = Heat Flux = 10
K = Thermal Conductivity = 20
ρ = Density = 6

c_p = ^K / _{q x ρ}
c_p = ²⁰ / _{10 x 6}
c_p = ²⁰ / ₆₀
c_p = 0.33

Therefore, the heat capacity at constant pressure is 0.33.

Nickzom Calculator – The Calculator Encyclopedia is capable of calculating the heat flux.

Now, Click on Solidification of Metal under Materials and Metallurgical

Now, Click on Heat Flux under Solidification of Metal

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), Density (ρ) and Heat Capacity at Constant Pressure (c_p).

Now, enter the values appropriately and accordingly for the parameters as required by the Thermal Conductivity (K) is 21, Density (ρ) is 12 and Heat Capacity at Constant Pressure (c_p) is 24.

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.