A heat flux of 2000 W m2 is incident on the surface of a two layer...

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A heat flux of 2000 W m2 is incident on the surface of a two layer composite slab shown in Figure 1. Layers of the slab are 15 cm and 10 cm thick and they have thermal conductivities of ki=12 W m-¹ K-¹ and k2= 7 W m-¹ K-¹, respectively. The hot side surface of the slab is found to be at 180 °C while the cold side surface is T2 °C. On the cold side, the heat is passed on to the surroundings at 25 °C both by convection and radiation (see Figure 1). If radiation is ideal (i.e., emissivity is 1) and the total heat transfer area is A m², then determine: i. the heat transfer coefficient related to radiation (hr) ii. the convective heat transfer coefficient (hc) iii. the percentage share of the heat flow between the convection and radiation processes (Qr and Qc) 180 °C Heat flux = 2000 W/m² Temperature gradient K₁ K₂ 15 cm 10 cm T₂ he, hr → Qr → Qc Ts= 25 °C A heat flux of 2000 W m2 is incident on the surface of a two layer composite slab shown in Figure 1. Layers of the slab are 15 cm and 10 cm thick and they have thermal conductivities of ki=12 W m-¹ K-¹ and k2= 7 W m-¹ K-¹, respectively. The hot side surface of the slab is found to be at 180 °C while the cold side surface is T2 °C. On the cold side, the heat is passed on to the surroundings at 25 °C both by convection and radiation (see Figure 1). If radiation is ideal (i.e., emissivity is 1) and the total heat transfer area is A m², then determine: i. the heat transfer coefficient related to radiation (hr) ii. the convective heat transfer coefficient (hc) iii. the percentage share of the heat flow between the convection and radiation processes (Qr and Qc) 180 °C Heat flux = 2000 W/m² Temperature gradient K₁ K₂ 15 cm 10 cm T₂ he, hr → Qr → Qc Ts= 25 °C

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Layer 1 thickness 15 cm Layer 2 thickness 10 cm Thermal conductivity of layer 1 k1 12 WmK Thermal co... View the full answer