Process Equipment and Plant Design

The clearance between two tubes in a shell and tube heat exchanger is known as ‘ligament’, whose minimum value is _____________ the outside diameter of the tube, but in no case it should be less than 4.5 mm?

by
The clearance between two tubes in a shell and tube heat exchanger is known as ‘ligament’, whose minimum value is _____________ the outside diameter of the tube, but in no case it should be less than 4.5 mm?

A. Equal to
B. Half
C. One fourth
D. Three fourth

Elastic failure of a material occurs, when the tensile stress equals yield strength, yield point or the elastic limit. Also, the elastic failure occurs according to maximum strain theory, when the maximum tensile strain equals (where, ζ = yield strength and E = modulus of elasticity) ?

by
Elastic failure of a material occurs, when the tensile stress equals yield strength, yield point or the elastic limit. Also, the elastic failure occurs according to maximum strain theory, when the maximum tensile strain equals (where, ζ = yield strength and E = modulus of elasticity) ?

A. E
B. ζ
C. ζ/E
D. E/ζ