Fuel economy in furnaces remains unaffected by stock thickness provided the material being heated is__________________?
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Answer: C. Both A. and B.
Explanation
If a material has very high thermal conductivity, internal temperature gradients remain negligible throughout the stock. Low emissivity combined with high thermal conductivity means stock thickness has minimal impact on fuel economy. Uniform internal heating eliminates the thermal resistance barriers typically caused by thick furnace stock. Heat transfer into solid stock depends on thermal conductivity, surface emissivity, and material thickness. Thick materials usually require longer heating times and higher furnace temperatures, increasing fuel consumption. Materials with exceptional thermal conductivity transfer heat rapidly from surface to core without internal resistance.
Furnace operators must evaluate stock thermal properties carefully to optimize heating schedules and fuel usage. Specialized metallurgical heating operations take advantage of material conductivity characteristics to save energy. Understanding transient heat conduction helps engineers prevent thermal shock in sensitive metallic stock. Option A is incomplete because high thermal conductivity is equally required to make stock thickness irrelevant. Option B is incomplete because low emissivity must accompany high conductivity to ensure unaffected fuel economy. Option D is incorrect because both listed material properties together make stock thickness negligible.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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