Chapter 11

Question 1

A procedure in which the direction of flow through the exchanger is reversed to remove solids that, for example, have accumulated in the inlet tubes of a heat exchanger.

Answer 1

Backwashing

Question 2

A metal plate that is placed inside a vessel or tank and is used to alter the flow of chemicals, facilitate mixing, or cause turbulent flow.

Answer 2

Baffle

Question 3

A measure of energy in the English system, referring to the heat required to raise the temperature of 1 pound of water 1°F at sea level.

Answer 3

British thermal unit (BTU)

Question 4

The amount of heat energy required to raise the temperature of 1 g of water by 1°C at sea level.

Answer 4

Calorie

Question 5

Flow that occurs when two fluids are flowing in the same direction.

Answer 5

Co-current flow

Question 6

An exchanger used to convert a substance from a vapor to a liquid.

Answer 6

Condenser

Question 7

The transfer of heat from one substance to another by direct contact.

Answer 7

Conduction

Question 8

The transfer of heat as a result of fluid movement.

Answer 8

Convection

Question 9

Occurs when two streams flow perpendicular (at 90° angles) to each other.

Answer 9

Cross flow

Question 10

Located on the end of a heat exchanger, it directs the flow of fluids into and out of the tubes.

Answer 10

Exchanger head

Question 11

Accumulation of deposits (such as sand, silt, scale, sludge, fungi, and algae) built up on the surfaces of processing equipment.

Answer 11

Fouling

Question 12

The transfer of energy from one object to another as a result of a temperature difference between the two objects.

Answer 12

Heat transfer

Question 13

A process to process heat exchanger. Interchangers use hot process fluids on the tube side and cooler process fluids on the shell side. Also known as cross exchanger.

Answer 13

Interchanger

Question 14

A streamline flow that occurs when the Reynolds number is low (at very low fluid velocities).

Answer 14

Laminar flow

Question 15

Occurs in a heat exchanger when the shell flow and the tube flow are parallel to one another.

Answer 15

Parallel flow

Question 16

A heat exchanger that adds heat to some substance prior to a process operation.

Answer 16

Preheater

Question 17

The transfer of heat through electromagnetic waves (example warmth emitted from the sun).

Answer 17

Radiation

Question 18

A tubular heat exchanger, placed at the bottom of a distillation column or stripper, that is used to supply the necessary column heat.

Answer 18

Reboiler

Question 19

A number used in fluid mechanics to indicate whether a fluid flow in a particular situation will be smooth or turbulent.

Answer 19

Reynolds number

Question 20

The outer casing, or external covering of a heat exchanger.

Answer 20

Shell

Question 21

The measure of the thermal energy of a substance (example the “hotness” or “coldness”) that can be determined using a thermometer.

Answer 21

Temperature

Question 22

A group of fixed, parallel tubes though which process fluids are circulated.

Answer 22

Tube bundle

Question 23

A formed metal plate with drilled holes that allows process fluids to enter the tube bundle.

Answer 23

Tube sheet

Question 24

flow that occurs when a dimensionless number (Reynolds number) is above 10,000 (at high velocities).

Answer 24

Turbulent flow

Question 25

Devices that are used to transfer (exchange) heat from one substance to another without the two process fluids physically contacting each other. Without this many processes could not occur properly.

Answer 25

Heat exchangers

Question 26

Heat can be transferred through conduction, convection, or radiation. However, the primary modes of heat transfer in the process industries are:

Answer 26

conduction and convection

Question 27

1BTU is equivalent to:

Answer 27

252 calories

Question 28

The term calorie, with a capital C found on food labels and in diet books is really 1,000 of the calories referred to in this chapter. That means one BTU is actually equivalent to:

Answer 28

252,000 of the calories we eat!

Question 29

Heat is commonly transferred by three methods:

Answer 29

conduction, convection, and radiation

Question 30

Example of conduction

Answer 30

frying pan

Question 31

Example of convection

Answer 31

hair dryer

Question 32

Example of radiation

Answer 32

sunlight

Question 33

consist of a series of thin plates that are mounted on a frame with alternating hot and cold fluids.

Answer 33

Plate and frame heat exchangers

Question 34

a group of fixed or parallel tubes through which process fluids are circulated.

Answer 34

Tube bundle

Question 35

is a flat plate to which the tubes in a heat exchanger are fixed.

Answer 35

Tube sheet

Question 36

consists of a group of fixed or parallel tubes, a tube sheet, baffles, and tie rods.

Answer 36

Tube bundle

Question 37

Heat exchangers are used to transfer heat between:

Answer 37

hot and cold streams

Question 38

Which of the following is the flow characteristic that occurs when the tube side stream and the shell side stream flow in the opposite directions?

Answer 38

Parallel flow

Question 39

Components that are found in a heat exchanger:

Answer 39

channel cover, baffle/divider, and tube sheet

Question 40

A ________________ is the piece of equipment that is bolted to the outside end of the channel to retain exchanger fluid and provide access for cleaning.

Answer 40

channel cover

Question 41

Which of the following pieces of equipment is used to convert a vapor to a liquid?

Answer 41

condenser

Question 42

Which of the following is not a potential problem in heat exchangers?

Answer 42

chemical balance

Question 43

Provides circulation based on density differences.

Answer 43

Thermosiphon reboiler

Question 44

Used to cool hot liquids.

Answer 44

Cooler

Question 45

Used to cool gas from a furnace.

Answer 45

Transfer line exchanger

Question 46

Uses cooling to convert a substance from a vapor to a liquid.

Answer 46

Condenser