Process Technology Equipment exam 3

thin material transfers heat better, fins create turbulence

Fins are added to tubes because

Convection

Fluids when warmer molecules move toward coller moecules.

Tube-and-shell pressure rating

Fouling resistance is determined by all of the following except the

forced, induced

Mechanical draft towers use fans to force air in (_______________ draft) or pull air out (_______________ draft).

water distribution header, hot water inlet to cooling tower

A pipe that evenly disperses hot water over the fill of a cooling tower is

increasing fluid velocity, lowering the temperature, adding inhibitors

A process technician can reduce fouling in a heat exchanger by

Kettle reboiler

A shell-and-tube heat exchanger with a vapor disengaging cavity, used to supply heat for separation of lighter and heavier componenets in a distillation system and to maintain heat balance.

parallel flow

A term applied to fluid flow that is equally distributed to multiple pieces of equipment. Example is heat exchanger

cross flow

A term used to describe flow in a heat exchanger where shell-side flow vertically crosses the horizontal tube flow is

counter flow

A term used to describe flow in a heat exchanger where tube-side flow and shell-side flow go in opposite directions is

parallel flow

A term used to describe flow in a heat exchanger where tube-side flow and shell-side flow go in the same directions is

multi-pass, u-tube, floating head

A type of heat exchanger that channels the tube-side flow across the tube bundle more than once is

kettle

A type of heat exchanger that uses a tubular bundle to heat and flash a liquid in an over-sized shell with a vapor disengaging cavity is a

forced, slows-down, 20% efficiency decrease

Air moves through a (forced draft or induced draft) at a higher rate. What happens to the flow rate at the discharge point?

radiant

All of the following are examples of heat transfer found in a heat exchanger except

Basin heaters

Are designed to keep cooling system water from freezing during the winter months.

Longitudinal baffles

Are used inside the shell to split or divide the flow, increase velocity, and provide superior heat transfer capabilities.

10%, 20%

Sensible heat transfer accounts for _______________ to _______________ of the cooling effect in a cooling tower

section

Shell and tube nomenclature includes all of the following except

Air intake louvers

Slats located at the bottom or sides of a cooling tower to direct airflow

thermal shock

Sudden temperature changes that result in the rapid expansion or contraction of metal is

Basin

Concrete storage compartment located at the bottom of the cooling tower.

Turbulent flow

random movement or mixing in swirls and eddies of a fluid.

Laminar flow

streamline flow that is more or less unbroken; layers of liquid flowing in a parallel path.

plenum

the open area directly under the fan.

static film

A layer of fluid that tends to adhere to the walls of a heat exchanger is referred to as

impingement

A baffle that is designed to deflect high velocity fluids inside a heat exchanger are called

fouling

A common term used to describe the internal buildup on the surface area of a heat exchanger that results in restricted flow is

it produces air flow; mechanical or natural, the air flows in relation to the downward flow of water; cross, or counter current

A cooling tower is classified by how

Channel head

A device mounted on the inlet side of a shell and tube heat exchanger that is used to channel flow in a multipass heat exchanger is called the

splash bar

A device used in a cooling tower to break up and redirect the flow of falling water is a

air-cooled heat exchanger

A fin fan is an example of a(n)

double pipe

A hairpin heat exchanger is an example of

drift eliminators

Devices used in a cooling tower to keep water from blowing out are called

Drift eliminators

Devices used in a cooling tower to keep water from blowing out.

80%, 90%

Evaporative cooling accounts for _______________ to _______________ of the cooling effect in a tower.

Baffles

Evenly spaced partitions in a shell-and tube heat exchanger that support the tubes, prevent vibration, control fluid velocity and direction, increase turbulent flow, and reduce hot spots.

Conduction

Heat energy is transferred through solid objects such as tubes, heads, baffles, plates, fins, and shell.

electromagnetic wave intensity

Heat exchanger effectiveness is linked to all of the following except

Plate and frame

Heat exchangers are easy to clean and have high heat transfer coefficients.

plate and packed

Heat exchangers can be found in all of the following categories except

sensible heat

Heat that can be measured or sensed is referred to as

power plants

Hyperbolic towers are primarily designed for service in what industry?

Fouling

Internal buildup on the surface area of a heat exchanger that results in a restriction is referred to as

Segmental baffles

Often used in horizontal shell-and-tube heat exchangers.

shell inlet valve #3- steam

On a simple shell and tube heat exchanger, a process technician would close which of the following valves first?

tube outlet valve #2- process fluid 325 F

On a simple shell and tube heat exchanger, a process technician would turn the device into a bomb if he closed which of the following valves first.

Fill

Plastic or wood surfaces that direct airflow and provide for contact of water and air in a cooling tower

Wet-bulb temperature

The air temperature as measured by a thermometer that takes into account the relative humidity.

Dry-bulb temperature

The air temperature as measured without taking relative humidity into account.

differential pressure, Δ P (delta P)

The difference between inlet and outlet pressures is commonly referred to as

personnel

The efficiency of a tower is tied to all of the following factors except

u-tube

The heat exchanger that is designed to take the highest flow rates and largest temperature differences is

relative humidity

The measure of how much water the air has absorbed at a given temperature is the

relative humidity

The measurement of how much water the air has absorbed at a given temperature is

wind velocity

The rate of air flow in a natural draft cooling tower depends primarily on

scale

The result of dissolved solids adhering to internal surfaces of equipment in the form of deposits is

Cell

The smallest subdivision of a cooling tower that can function as an independent unit. Some cooling tower systems have multiple.

Approach to tower

The temperature difference between the water leaving a cooling tower and the wet-bulb temperature of the air entering the tower.

corrosion

This results when electrochemical reactions occur between metal surfaces and surrounding hot water that results in the gradual wearing away of metal.

Horizontal baffles

Used in vapor-phase or all-liquid-phase operations.

louvers

Vents located on the side of a cooling tower are called

The air temperature as measured by a thermometer that takes into account the relative humidity

WBT or wet-bulb temperature is the

Laminar and Turbulent

What are the two major classifications of fluid flow?

vertical baffles, impingement baffle,longitudinal baffles

What is the name of the metal plates located inside a shell and tube heat exchanger that are designed to increase turbulent flow and reduce hotspots?

Natural, mechanical

_______________ draft cooling towers use natural forces to bring air into a cooling tower while _______________ draft towers use fans to induce or force air into a tower.

Tub head

a floating head heat exchanger is firmly attached to the tube sheet.

Impingement baffles

are used to protect tubing from direct fluid impact.

Cooling tower

box-shaped collection of multi-layered wooden slats and louvers that direct air flow and breaks up water as it falls from the top of the tower or water distribution header, internal design of the tower that ensures good air and water contact

shell-an-tube

heat exchanger can be used to heat and cool a substance

Hairpin

heat exchangers are relatively easy to clean and install.

Sensible heat

heat that can be measured or sensed by a change in temperature.