In a manufacturing process, a transparent film is being bonded to a substrate as shown in the sketch. To cure the bond at a temperature To, a radiant source is used to provide a heat flux qő (W/m²) , all of which is absorbed at the bonded surface. The back of the substrate is maintained at T₁ while the free surface of the film is exposed to air at I and a convection heat transfer coefficient h. Air To h ↓ Lf Film Substrate 90 Ly= 0.25 mm k= 0.025 W/m-K L = 1.0 mm Bond, To k, = 0.05 W/m-K T₁ (a) Show the thermal circuit representing the steady-state heat transfer situation. Be sure to label all elements, nodes, and heat rates. Leave in symbolic form. (b) Assume the following conditions: T = 20°C, h = 50 W/m² K, and T₁ = 30°C. Calculate the heat flux d that is required to maintain the bonded surface at To = 60°C.

In a manufacturing process, a transparent film is being bonded to a substrate as shown in the sketch. To cure the bond at a temperature To, a radiant source is used to provide a heat flux qő (W/m²) , all of which is absorbed at the bonded surface. The back of the substrate is maintained at T₁ while the free surface of the film is exposed to air at I and a convection heat transfer coefficient h. Air To h ↓ Lf Film Substrate 90 Ly= 0.25 mm k= 0.025 W/m-K L = 1.0 mm Bond, To k, = 0.05 W/m-K T₁ (a) Show the thermal circuit representing the steady-state heat transfer situation. Be sure to label all elements, nodes, and heat rates. Leave in symbolic form. (b) Assume the following conditions: T = 20°C, h = 50 W/m² K, and T₁ = 30°C. Calculate the heat flux d that is required to maintain the bonded surface at To = 60°C.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.45P

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