Q4. Calculate the minimum heat flux using an energy balance at the material surface and the time-to-ignition if the ignition temperature is 150 "C, ambient temperature is 30 "C. The thermal properties of aluminium alloy balls ( K- 4.8 W/m.K, C, 950 J/kg.K, 2770 kg/m. The emissivity to the surface is 0.8, Stefan Boltzman constant is 5.67x10 W/m.K. Convictive heat transfer coefficient is 12 W/m'K and net heat flux into the material surface is 20 KW/m².

Q4. Calculate the minimum heat flux using an energy balance at the material surface and the time-to-ignition if the ignition temperature is 150 "C, ambient temperature is 30 "C. The thermal properties of aluminium alloy balls ( K- 4.8 W/m.K, C, 950 J/kg.K, 2770 kg/m. The emissivity to the surface is 0.8, Stefan Boltzman constant is 5.67x10 W/m.K. Convictive heat transfer coefficient is 12 W/m'K and net heat flux into the material surface is 20 KW/m².

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Concept explainers

Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.

Question

Q4. Calculate the minimum heat flux using an energy balance at the material surface and
the time-to-ignition if the ignition temperature is 150 "C, ambient temperature is 30 "C.
The thermal properties of aluminium alloy balls ( K- 4.8 W/m.K, C, 950 J/kg.K,
2770 kg/m. The emissivity to the surface is 0.8, Stefan Boltzman constant is 5.67x10
W/m.K. Convictive heat transfer coefficient is 12 W/m'K and net heat flux into the
material surface is 20 KW/m.

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