1
GATE ME 1990
Subjective
+5
-0
An iron rod $$\left( {K = 41.5W/mK} \right)$$ of $$15mm$$ diameter and $$160mm$$ long extends out of a hot surface of temp $${150^ \circ }C$$ into environment at $${36^ \circ }C.$$The free end of the rod is insulated. If the film heat transfer coefficient is $$25W/{m^2}K,$$ calculate the rate of heat flowing out of the hot surface through the rod and the temp at the insulated end of the rod.
2
GATE ME 1989
Subjective
+5
-0
The total efficiency, $${\eta _t}$$ for a finned surface may be defined as the ratio of the total heat transferred by the combined area of the fins, $${A_r},$$ and the exposed surface to that by the total area, $$A$$, if it were maintained at the base temp, $${T_0}.$$ Assuming uniform heat transfer coefficient over the entire surface, derive an expression for the relationship between efficiency and effectiveness of the fin.
Questions Asked from Fin Design and Transient Heat Conduction (Marks 5)
Number in Brackets after Paper Indicates No. of Questions
GATE ME Subjects
Engineering Mechanics
Machine Design
Strength of Materials
Heat Transfer
Production Engineering
Industrial Engineering
Turbo Machinery
Theory of Machines
Engineering Mathematics
Fluid Mechanics
Thermodynamics
General Aptitude