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What is the next radiant interchange per square meter for two very large plates at temperatures 800 K and 500 K respectively ? (The emissivity of the hot and cold plates is 0.8 and 0.6 respectively. Stefan Boltzmann constant is 5.67 × 10-8 w/m2 K4)

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  1. 1.026 kW
  2. 10.26 kWm2
  3. 102.6 kWm2
  4. 1026 kWm2

Answer (Detailed Solution Below)

Option 2 : 10.26 kWm2
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Concept:

Radiation heat exchange (q) between two infinitely long parallel plates is given by:

    

Calculation:

Given T1 = 800 K, T2 = 500 K; ϵ1 = 0.8, ϵ2 = 0.6;

Now the net heat exchange will be 

⇒ q = 10268.123 W/m2;

⇒ q = 10.26 kW/m2;

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