In a shell and tube heat exchanger having triangular pitch, the shell side equivalent diameter is given by

In a shell and tube heat exchanger having square pitch, the shell side equivalent diameter is given by (where, P = pitch, d = outside diameter of the tube)

A

$$\frac{{4\left( {{{\text{p}}^2} - \pi {{\text{d}}^2}/4} \right)}}{{\pi {\text{d}}}}$$

B

$$\frac{{{{\text{p}}^2} - \pi {{\text{d}}^2}/4}}{{\pi {\text{d}}}}$$

C

$$\frac{{4{{\text{p}}^2}}}{{\pi {\text{d}}}}$$

D

$$\frac{{\pi {\text{d}}}}{{4{{\text{p}}^2}}}$$

Air is to be heated by condensing steam. Two heat exchangers are available (i) a shell and tube heat exchanger and (ii) a finned tube heat exchanger. Tube side heat transfer area are equal in both the cases. The recommended arrangement is

A

Finned tube heat exchanger with air inside and steam outside

B

Finned tube heat exchanger with air outside and steam inside

C

Shell and tube heat exchanger with air inside tubes and steam on shell side

D

Shell and tube heat exchanger with air on shell side and steam inside tubes

Triangular pitch tube layout as compared to square pitch in a shell and tube heat exchanger

A

Permits the use of less tubes in a given shell diameter

B

Facilitates comparatively easier external cleaning because of large clearance

C

Permits the use of more tubes in a given shell diameter

D

Both B and C

In a shell and tube heat exchanger, putting a longitudinal baffle across the shell, forces the shell side fluid to pass __________ through the heat exchanger.

A

Once

B

Twice

C

Thrice

D

Four times

In a shell and tube heat exchanger, square pitch compared to triangular pitch

A

Gives a higher shell side pressure drop

B

Gives a lower shell side pressure drop

C

Can pack more surface area into a shell of given diameter

D

Both (A) and (B)

E

Both (A) and (C)

In a shell and tube heat exchanger, triangular pitch arrangement as compared to square pitch arrangement

A

Results in higher shell side pressure drop

B

Can accomodate less number of tubes for a given shell diameter

C

Facilitates easier shell side cleaning; hence is more suitable for handling high dirt factor shell side fluid

D

Creates relatively lower turbulence on the shell side resulting in lower shell side heat transfer co-efficient

For the same heat load and mass flow rate in the tube side of a shell and tube heat exchanger, one may use multipass on the tube side, because it

A

Decreases the pressure drop

B

Decreases the outlet temperature of cooling medium

C

Increases the overall heat transfer coefficient

D

None of these

Shell side heat transfer co-efficient in case of square pitch as compared to the triangular pitch under similar condition of fluid flow and tube size is

A

More

B

Same

C

Less

D

Twice

In a shell and tube heat exchanger, the tube side heat transfer co-efficient just at the entrance of the tube is

A

Infinity

B

Zero

C

Same as average heat transfer co-efficient for tube side

D

None of these

In a shell and tube heat exchanger for a given heat transfer surface area, smaller diameter tubes are favoured as compared to larger diameter ones ; because the smaller diameter tubes

A

Are easier to clean

B

Are less prone to fouling

C

Can be fitted into a smaller shell diameter hence the cost of the heat exchanger would be less

D

None of these

In a shell and tube heat exchanger having triangular pitch, the shell side equivalent diameter is given by

Related Questions