How to Calculate and Solve for Enthalpy of Wet Stream | Enthalpy

Last Updated on April 23, 2022

The image above represents enthalpy for wet steam.

To compute for enthalpy for wet steam, three essential parameters are needed and these parameters are Dryness Fraction (x), Enthalpy of Water (h_f) and Enthalpy of Vapourization (h_fg).

The formula for calculating enthalpy for wet steam:

h = h_f + xh_fg

Where:

h = Enthalpy of Wet Steam
x = Dryness Fraction
h_f = Enthalpy of Water
h_fg = Enthalpy of Vapourization

Let’s solve an example;
Find the enthalpy of wet steam when the dryness fraction is 4, the enthalpy of water is 6 and the enthalpy of vapourization is 8.

This implies that;

x = Dryness Fraction = 4
h_f = Enthalpy of Water = 6
h_fg = Enthalpy of Vapourization = 8

h = h_f + xh_fg
h = 6 + 4 x 8
h = 6 + 32
h = 38

Therefore, the Enthalpy of Wet Steam is 38 J/Kg.

Calculating the Dryness Fraction when the Enthalpy of Wet Steam, the Enthalpy of Water and the Enthalpy of Vapourization is Given.

x = ^{h – h_f} / _hfg

Where;

x = Dryness Fraction
h = Enthalpy of Wet Steam
h_f = Enthalpy of Water
h_fg = Enthalpy of Vapourization

Let’s solve an example;
Find the dryness fraction when the enthalpy of wet steam is 14, the enthalpy of water is 8 and the enthalpy of vapourization is 2.

This implies that;

h = Enthalpy of Wet Steam = 14
h_f = Enthalpy of Water = 8
h_fg = Enthalpy of Vapourization = 2

x = ^{h – h_f} / _hfg
x = ^{14 – 8} / ₂
x = ⁶ / ₂
x = 3

Therefore, the dryness fraction is 3.

Calculating the Enthalpy of Water when the Enthalpy of Wet Steam, the Dryness Fraction and the Enthalpy of Vapourization is Given.

h_f = h – xh_fg

Where:

h_f = Enthalpy of Water
h = Enthalpy of Wet Steam
x = Dryness Fraction
h_fg = Enthalpy of Vapourization

Let’s solve an example;
Find the enthalpy of water when the enthalpy of wet steam is 20, the dryness fraction is 4 and the enthalpy of vapourization is 3.

This implies that;

h = Enthalpy of Wet Steam = 20
x = Dryness Fraction = 4
h_fg = Enthalpy of Vapourization = 3

h_f = h – xh_fg
h_f = 20 – (4)(3)
h_f = 8

Therefore, the enthalpy of water is 8 J/Kg.

Calculating the Enthalpy of Vapourization when the Enthalpy of Wet Steam, the Dryness Fraction and the Enthalpy of Water is Given.

h_fg = ^{h – h_f} / _x

Where:

h_fg = Enthalpy of Vapourization
h = Enthalpy of Wet Steam
x = Dryness Fraction
h_f = Enthalpy of Water

Let’s solve an example;
Find the enthalpy of vapourization when the enthalpy of wet steam is 32, the dryness fraction is 10 and the enthalpy of water is 2.

This implies that;

h = Enthalpy of Wet Steam = 32
x = Dryness Fraction = 10
h_f = Enthalpy of Water = 2

h_fg = ^{h – h_f} / _x
h_fg = ^{32 – 2} / ₁₀
h_fg = ³⁰ / ₁₀
h_fg = 3

Therefore, the enthalpy of vapourization is 3 J/Kg.

Nickzom Calculator – The Calculator Encyclopedia is capable of calculating the enthalpy of wet steam.

Now, Click on Chemical Reaction Thermodynamics under Materials and Metallurgical

Now, Click on Enthalpy under Chemical Reaction Thermodynamics

Now, Click on Enthalpy of Wet Steam under Enthalpy

The screenshot below displays the page or activity to enter your values, to get the answer for the enthalpy of wet steam according to the respective parameter which is the Dryness Fraction (x), Enthalpy of Water (h_f) and Enthalpy of Vapourization (h_fg).

Now, enter the values appropriately and accordingly for the parameters as required by the Dryness Fraction (x) is 4, Enthalpy of Water (h_f)  is 6 and Enthalpy of Vapourization (h_fg) is 8.

Finally, Click on Calculate

As you can see from the screenshot above, Nickzom Calculator– The Calculator Encyclopedia solves for the enthalpy of wet steam and presents the formula, workings and steps too.