Two horizontal steam mains with diameters 5 cm and 15 cm are to be lai – McqOptions

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1.	Two horizontal steam mains with diameters 5 cm and 15 cm are to be laid in a boiler house that any mutual heat effect is precluded. The mains are at the same surface temperature of 500 degree Celsius whilst the ambient air is at 50 degree Celsius. Workout the ratios of the heat transfer coefficients
A.	0.136
B.	1.316
C.	2.136
D.	3.136
Answer» C. 2.136

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