HEAT TRANSFER QUIZ

Is thinner than hydrodynamic boundary layer

Is thicker than hydrodynamic boundary layer

Disappears

And the hydrodynamic boundary layer are identical

contaminated cooling

smooth clean

polished

clean and dirt free

Thermal diffusivity

Heat transfer co-efficient

Thermal conductivity

Stefan-Boltzman constant

Cross

Parallel

Counter

None of these

0.06 to 120

l to 50

0.6 to 120

1 to 103

Flows outside the tubes

Flows through the tube

Can flow either inside or outside the tubes

Should not be used as it gives very high pressure drop

Cost of equipment is lower

There is no mist formation

Heat transfer co-efficient are high

There is no risk of contamination

Decreases

Remains unchanged

Increases

Increases or decreases depending on number of shell passes

Brinkman number

Peclet number

Schmidt number

Stanton number

Thin walled having the value of Ao Ai/< 2

Having the value of Ao/Ai > 2

Both B and C

Thick walled