Overall heat transmission

It is necessary to consider the heat transfer from inside air to outside air. The heat transfer processes include conduction, convection, and radiation simultaneously.

T„	Ri	«2
1. O’	1
X	<
	Qi	Q2
Q <

R V

1Til T.

X

11+1

X-
X.

Ti

Rtv

Rri

X

Q Ro = T0 — Ti

Q Ri = Ti — T2

Q Ri= T„+i — T„

___ q Ri = Tn^j — Tj___________

+) q[R0+(ERJ)+RJ = T0-TI

J=i

T — T

Q =— 1——————————-

R0+(Јr,)+r,

J=i

N

R =R0 + Rj) + R; (Overall thermal resistance)

J=i

U =1/R (Overall heat transfer coefficient)

Example 5.3

Continue to work on example 6.1 to determine the outdoor and indoor air temperatures.

Solution:

O

Posted in Fundamentals of Heating. Ventilating, and Air-Conditioning