Continued The Plank Distribution Eba C lecstar C1=3.742*108w:4m4/m2 C2=1.438*104um·K Whenλ=const T1一EAb↑
Continued The Plank Distribution [ 1] 5 / 1 2 − = b C T e C E λ λ λ C m K C w m m = ⋅ = ⋅ μ μ 4 2 8 4 2 1 1.438 *10 3.742 *10 / When λ=const T Eλ,b
Continued Wien's Displacement Law AT=C3 C3=2897.8,Um·K Sun,at 5800K,as black body, λ=C3/5800K=0.5m max Visible Range
Continued Wien’s Displacement Law λmaxT = C3 C3 = 2897 .8μm ⋅ K Sun, at 5800K, as black body, λmax = C3 / 5800K = 0.5μm Visible Range
109 visible spectral region 入maxT=2898以m-K Solar radiation 10 5800K 2000K 104 1000K 800K 10 300K 100K 102 10-3 50K 104 0.1 0.2 0.40.6 1 2 46 10 20 4060100 Wavelength,入(um) FIGURE 12.13 Spectral blackbody emissive power. Plank distribution curve
Plank distribution curve
Continued ▣Total Emissive Power E=fExda=l C exp(C2/λT)I刂 ◇E6=o4 0=5.67*10-8W/m2.K4 ▣Band Emission
Continued Total Emissive Power Band Emission ∞ ∞ − = = 0 0 2 5 1 , [exp( / ) 1] λ λ λ λ λ d C T C Eb E bd 4 Eb =σT 8 2 4 = 5.67*10 W / m ⋅K − σ