Related Resources: calculators

Heat Radiation of a Surface


Heat Radiation of a Surface
Fraction of heat energy absorbed,α = absorbtivity
Fraction of heat energy reflected, ρ = reflectivity
Fraction of heat energy passed thru.,τ = transmissivity (transparent; solids, liquids, & gasses)
By definition,α + ρ + τ = 1.00
 
Black Body Radiation
An ideal black body absorbs all incidentradiation so that,α = 1.00
therefore,ρ = 0 and τ = 0
  Input Data  
t =
deg C
S.I. absolute temperature,Tk = t + 273.2 deg K
Answer:Tk = deg K
  Input Data  
t =
deg F
U.S. absolute temperature,Tr =
t + 459.8 deg R
Answer:Tr =
deg R
 
Radiation Example Input Data  
Material surface emissivity,e =
-
Stefan-Boltzmann constant,σ =
W / m^2-K^4
Dimension,L1 =
m
Dimension,L2 =
m
Surface temperature,t1 =
deg C
  Results  
Area,A =
L1*L2  
Answer:A =
m^2
Absolute temperature.T =
C + 273  
T =
deg Abs
Radiant thermal flux reflected,Q =
e*σ*T^4  
Answer:Q =
Watts