Question

What is the sensible heat factor during the heating and humidification process equal to?

Where, H₁ = Total heat of air entering the heating coil

H₂ = Total heat of air leaving the heating coil

H₃ = Total heat of air at the end of the humidification

1. \(\frac {H_1+H_2}{H_3-H_1}\)
2. \(\frac {H_2-H_1}{H_3-H_1}\)
3. \(\frac {H_1+H_2}{H_1-H_2}\)
4. \(\frac {H_3-H_1}{H_2-H_1}\)

Answer 1

Correct Answer - Option 2 : \(\frac {H_2-H_1}{H_3-H_1}\)

Concept:

Sensible heat, Latent heat and Total heat

• Sensible heat (S.H) is the heat which increases or decreases the temperature of the body.
• Latent heat (L.H) is the heat which is absorbed or released during phase change
• Total heat (T.H) is the sum of sensible heat and latent heat.

T.H = S.H + L.H

Sensible heat factor (S.H.F)

The sensible heat factor is the ratio of sensible heat to total heat.

\(\;\;SHF =\frac{SH}{SH+LH}= \frac{{{\rm{S}}.{\rm{H}}}}{{{\rm{T}}.{\rm{H}}}} \)

Here sensible heat SH = H₂ - H₁

Total heat TH = H₃ - H₁

Therefore, 

\(SHF= \frac{{{{\rm{H}}_2} - {{\rm{H}}_1}}}{{{{\rm{H}}_3} - {{\rm{H}}_1}}}\)