ARCH SCI FINAL

what determines the seasons?

the tilt of the earths axis

(T/F) In the Northern Hemisphere, summer happens when the Earth is closest to the Sun.

False

What does ASHRAE stand for?

American Society of Heating, Refrigerating and Air-Conditioning Engineers

The human body generates heat in a process called metabolism. Depending on physical activity, rate of heat gain can be high or low. Metabolism is defined as ...............

DB Temperature and Wind Speed

Wind Chill, as a measure of equal comfort, takes into account the combined effect of ..........

DB Temperature and Wind Speed

Operative Temperature, as a measure of equal comfort, takes into account the combined effect of ..........

DB Temperature and Mean Radiant Temperature

Heat Index, as a measure of equal comfort, takes into account the combined effect of ..........

DB Temperature and % Relative Humidity

Effective Temperature, as a measure of equal comfort, takes into account the combined effect of ..........

DB Temperature and % Relative Humidity

For a location at a given latitude, sun angles can be calculated using this equation [LAT + ALT = 90o], hence Altitude is the vertical sun angle at solar noon on the two equinoxes. This equation is true ....
a. Only in the Northern Hemisphere
b. Everywhere on the planet
c. Only in the Southern Hemisphere

B

Choose the correct statement that describes the rotation of earth around its own axis and its orbiting around the sun.
a. Earth rotates around its own axis clockwise and orbits around the sun clockwise (north is up).
b. Earth rotates around its own axis clockwise, but orbits around the sun counterclockwise (north is up).
c. Earth rotates around its own axis counterclockwise and orbits around the sun counterclockwise (north is up).
d. Earth rotates around its own axis counterclockwise, but orbits around the sun clockwise (north is up).

C

For solar control at the Equator, is it more important to shade the south facade, the north facade, or both?

Both north and south facades.

At the Equator, when is the strongest sun?

On the two Equinoxes (March 21 & September 21)

(T/F) Daytime is always longer than nighttime in the summer, and nighttime is always longer than daytime in the winter (including at the Equator)?

False, equator is same times per day

(T/F) For simplification, sunpath diagrams assume that all days are 24 hours and solar noon always happens at 12:00 clock. However, in fact not all days are 24 hours and solar noon doesn't always happen at 12:00 clock.

True

How much energy us consumed to operate buildings? (source energy)

40-41%

What is sustainability?

Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.

What is our biggest and only utility company?

The sun E=m*c^2

(T/F) A lesson learned from "Easter Island" is that population, development, and consumption of natural resources may increase indefinitely without causing damage to the ecosystem.

False

(T/F) At any location on the planet, at solar noon on the two equinoxes (approximately on March 21st and September 21st), the vertical sun (altitude) is equal to the latitude of the location.

False

(T/F) For buildings to be part of the solution of the global energy problem, they need to be all electric in the future (100% electric, with no natural gas).

True

(T/F) Electromagnetic waves emitted by the sun and received on the surface of planet earth share the same exact wavelength and frequency.

False

Solar energy is generated in the sun as a result of nuclear fusion between Hydrogen atoms, a process in which mass is converted into energy.
a. Yes, nuclear fusion happens between Hydrogen atoms.
b. No, no mass is converted into energy in the sun
c. No, nuclear fusion happens between Helium atoms.

A

(T/F) Overcast sky looks blue because the moisture molecules in atmosphere equally scatter all light wavelengths

false

(T/F) The real color of sky (space) is white. However, during daytime, clear sky looks blue because the scattered light energy in the atmosphere is dominated by the color blue (blue wavelength).

false

Electric power plants use a variety of energy sources. All forms of energy used to generate electricity are of solar origin, with the exception of ..........

Nuclear Power

(T/F) The industrial revolution (extensive use of energy) enabled mankind to be more productive and improved the quality of life (on average, but not for all).

true

Plants store solar energy (carried by the electromagnetic waves) in a chemical form, in a process called Photosynthesis. Photo synthesis can be defined as ..........

Building up organic matter

(T/F) An average person in a developed country receives more and better services (such as, education, health care, transportation, ... etc.), although consuming less energy than a person in a developing country.

false

Solar energy travels from the Sun to Earth in a form of .................

-Electromagnetic waves-Light and thermal radiation-Radiant energy

(T/F) In the Northern Hemisphere, winter happens when Earth is closest to the sun (Dec. 21st), while in the Southern Hemisphere, winter happens when Earth is farthest from the sun (June 21st).

true

(T/F) The Psychometric Chart is used to visualize human thermal comfort, indoor, and outdoor moist air conditions. When at least two (related or unrelated) properties of the moist-air are known, a condition can be defined and plotted on the chart.

false

(T/F) When moist air is cooled down, its wet bulb temperature drops down too. In this cooling process, however, its relative humidity increases.

true

(T/F) The psychrometer (also known as the sling thermometer) can only measure the dry bulb temperature, and not the wet bulb thermometer.

false

(T/F) Equal (thermal) comfort is a result of equal rate of heat loss to the surrounding environment, regardless of the mechanism through which the body loses heat.

true

The six factors that affect human comfort include 4 environmental factors, which are: _________, __________, _________, and _________, and two occupant-related factors, which are: _________, and _________.

1. dry bulb Temperature
2. Relative Humidity
3. Wind Speed/Air Motion
4. MRT/Radiation
5. Clothing
6. Metabolism

Solar Altitude

vertical angle of the sun's position above the horizon

Solar Azimuth

horizontal angle of the sun, above the horizon

According to the UN (United Nations), quality of life can be assessed on....

Illiteracy of life, infant mortality rate, and life expectancy

At which condition do we feel comfortable?

When the rate of heat loss is equal to the rate of heat gain.

Humans' environment impact on the planet is function in:

Population, Affluence per Capita, Technology

Since latent heat is the heat required to change the phase of matter, its level can be measured by:
a. dry bulb temperature
b. globe thermometer
c. none of the above

C. None of the above

At any location at 40 degrees South Latitude (southern hemisphere), solar altitude angle at solar noon on the two equinoxes is:
a. 60 degrees
b. 50 degrees
c. 40 degrees

B. 50 degrees
ALT=90-LATALT=90-40=50

In spaces where occupants perform more vigorous physical activity (in a gymnasium or a practice room), the set temperature (thermostat temperature) should be:

Lower than normal

When does condensation start when moist air is cooled down?

At its dew point temperature

In a room, the dry-bulb temperature is 72 degrees, however occupants feel warm. The reason is:

High relative humidity and warm glass of the curtain wall in summer

In a room, the dry-bulb temperature is 72 degrees, however occupants feel cold. The reason is:

High air flow and cold glass of the curtain wall in winter

In which case the wet bulb temperature of moist air is equal to its dry bulb?

at the saturation level, at the dew point, and at 100% relative humidity

Declination Angle and Season of June 21st

+23.5, summer solstice

sun is above the equator

Declination Angle and Season of March 21st and September 21st

+/- 0, equinoxes

sun is at the equator

Declination Angle and Season of December 21st

-23.5, winter solstice

sun is below the equator

What is the best shading system for north walls in the United States?

Vertical Fins

since buildings are not occupied during the night, in the peak heating load calculations, is there an outside air load considered?

Outside air load is considered.

because thermal resistance (R-value) of glass is typically much lower than opaque surfaces (walls and roofs), is the rate of heat transfer through glass higher or lower per sqft?

rate of heat transfer through glass is higher per sqft

The space setpoint (thermostat temperature):
a. should be higher in the summer than winter
b. should be higher in the winter than summer
c. should stay the same all seasons

A. should be higher in the summer than winter

ASHRAE Standard 62.1 requires a minimum volume of outside air ventilation based on:
a. area of the space
b. number of occupants in the space
c. typically both of the above

C. typically both of the above

area of the space
number of occupants in the space

typically, peak cooling load due to radiant heat gains, such as solar heat gain, electric lighting load, and peoples' load is:
a. smaller than the heat gain
b. equal to the heat gain
c. greater than the heat gain

A. smaller than the heat gain

The cooling load from electric lighting systems is the result of:
a. sensible heat gain only
b. latent heat gain only
c. both sensible and latent heat gains

a. sensible heat gain only

Glass type (for windows) affects:
a. Transmitted heat loss (heating)
b. Transmitted heat gain (cooling)
c. Solar load (cooling)
d. All of the above
e. A&B only
f. B&C only

d. All of the above

Transmitted heat loss (heating)
Transmitted heat gain (cooling)
Solar load (cooling)

Thermal capacity of the construction (i.e., room's floor) affects the cooling load due to:
a. solar heat gain through the windows without interior shading only
b. solar heat gain through the windows with interior shading only
c. both of the above

a. solar heat gain through the windows without interior shading only

in general, for the same floor area, which private office space may have a higher load?
a. a space facing a single orientation
b. a corner office

b. a corner office

Using a glass type with lower U-factor will:
a. reduce transmitted load
b. increase transmitted load

a. reduce transmitted load

IECC (2015) stands for:
a. International Environmental Control Code
b. International Energy Conservation Code
c. International Envelope Compliance Code

b. International Energy Conservation Code

When the IECC requires the installation of a vapor barrier within the envelope, it should be installed on which side of insulation?
a. Warm-in-summer side of insulation
b. Warm-in-winter side of insulation
c. Better on both sides of insulation

b. Warm-in-winter side of insulation

The code requires more thermal insulation in colder climates, when does it always require insulation for the slab-on-grade?
a. For heated slabs
b. For unheated slabs

a. For heated slabs

In English unites (I-P units), conductivity of a material is equal to the conductance of:
a. one foot thickness
b. one inch thickness
c. one centimeter thickness

b. one inch thickness

Write a brief on your understanding of building performance (high vs low loads)

low: the wall is the most efficient loading to the least heat loss
high: Outside air is latent

Suggest at least two energy efficient measures to reduce the peak cooling load in this art space.

1. change building color to be lighter
2. provide more shading for the window covers

Based on your peak cooling load calculations, should the cooling equipment dehumidify or humidify the outside air for ventilation? Why?

dehumidify due to the difference in humidity ratio being positive

in calculation of light and equipment load, load is multiplied x 3.4, refer to worksheet. What is the 3.4 in the equation?

conversion factor for units

in calculation of the solar cooling load (a radiant hear component), cooling load is lower than the solar heat gain, refer to the worksheet. Why is the cooling load lower than the heat gain?

because of the thermal lag factor, there will be a delay in the load due to the absorption of heat

In reference to the IECC (International Energy Conservation Code) , a code-compliant wall assembly must include the following control layers:
a. Water proofing + thermal insulation + vapor retarder
b. Thermal insulation + vapor retarder
c. Air barrier + thermal insulation + vapor retarder
d. All four control layers, I.
e., water proofing + air barrier + thermal insulation + vapor retarder.

d. All four control layers, i.e., water proofing + air barrier + thermal insulation + vapor retarder.

In reference to the IECC (International Energy Conservation Code), for the same climate zone
a. The building thermal energy requirements are the different for residential and commercial buildings.
b. The building thermal energy requirements are the same for residential and commercial buildings.

a. The building thermal energy requirements are the different for residential and commercial buildings.

In reference to the IECC (International Energy Conservation Code), a wall assembly should comply based on which of the following pathways?In reference to the IECC (International Energy Conservation Code), a wall assembly should comply based on which of the following pathways?
a. Either the Minimum R-value or the Maximum U-factor
b. Maximum U-factor only
c. Both of the Minimum R-value and Maximum U-factor
d. Minimum R-value of the thermal insulation (insulation component) only.

a. Either the Minimum R-value or the Maximum U-factor

When we check code compliance of steel frame construction with cold-formed metal studs, we should ...
a. Ignore thermal bridging through the metal studs, since it won't have a significant impact on the overall R-value of the wall assembly.
b. Account for thermal bridging through the metal studs which reduces the total R-value of the wall assembly.

b. Account for thermal bridging through the metal studs which reduces the total R-value of the wall assembly.

In commercial buildings, central sources of heating may be:
a. Boilers that supply hot water
b. Geo-exchange heat pumps that extract heat from the ground
c. Steam-to-water heat exchanger, when steam supply is provided by a central plant (district heating)
d. Any of the above

d. Any of the above

In commercial buildings, central sources of cooling may be:
a. Chilled water from a central plant
b. A water-cooled chiller
c. An air-cooled chiller
d. Geo-exchange heat pumps that reject heat to the ground
e. Any of the above

e. Any of the above

The four components of the refrigeration cycle (in the correct order) are:
a. Compressor, expansion valve, condenser, and evaporator
b. Compressor, condenser, expansion valve, and evaporator
c. Condenser, compressor, expansion valve, and evaporator

b. Compressor, condenser, expansion valve, and evaporator

Identify which type of heat pump is the air-cooled chiller:
a. Air-to-air HP
b. Air-to-water HP
c. Water-to-air HP
d. Water-to-water HP
e. Reversable air-to-water and water-to-airHP

c. Water-to-air HP

Identify which type of heat pump is the water-cooled chiller:
a. Air-to-air HP
b. Air-to-water HP
c. Water-to-air HP
d. Water-to-water HP
e. Reversable air-to-water and water-to-air HP

d. Water-to-water HP

Identify which type of heat pump is the geo-exchange heat pump (in cooling & heating):
a. Air-to-air HP
b. Air-to-water HP
c. Water-to-air HP
d. Water-to-water HP
e. Reversable air-to-water and water-to-air HP

e. Reversable air-to-water and water-to-air HP

Identify which type of heat pump is the DX unit (packaged unit):
a. Air-to-air HP
b. Air-to-water HP
c. Water-to-air HP
d. Water-to-water HP
e. Reversable air-to-water and water-to-air HP
f. It is not a heat pump

a. Air-to-air HP

Sizing central sources of heating and cooling is based on:
a. Annual energy consumption (total energy consumption in one year)
b. Peak load (highest load in the year)
c. EUI (Energy Use Intensity)
d. The average hourly load in the year
e. The lowest hourly load in the year

b. Peak load (highest load in the year)

The unit ventilator (a terminal unit in water systems) is commonly used in motels, hotels, and classrooms. Main reason for its selection is its ability to:
a. Provide individual control for every space (a thermostat in every room/thermal zone).
b. Provide simultaneous heating and cooling (for different rooms)
c. Provide fresh air for ventilation
d. All the above

d. All the above

The appropriate location of the air-cooled chillers is:
A. Inside the main mechanical room
B. Outside of the building on the ground C. On the roof.
D. In its own fire-rated room
E. Any of the above
F. B or C
G. A and D

F. B or C

Outside of the building on the ground

On the roof.

The appropriate location of the central boilers is:
A. Inside the main mechanical room with other mechanical equipment
B. Outside of the building on the ground. C. On the roof
D. In its own fire-rated room
E. Any of the above
F. B or C
G. None of the above

D. In its own fire-rated room

The appropriate location of the water-cooled chiller is:
A. Inside the main mechanical room
B. Outside of the building on the ground
C. On the roof
D. In its own fire-rated room
E. Any of the above
F. B or C
G. None of the above

A. Inside the main mechanical room

Select the most energy-efficient water system that can also provide simultaneous heating and cooling:
a. One-pipe finned tubes
b. Two-pipe finned tubes
c. Three-pipe fan coil units
d. Four-pipe fan coil units
e. None of the above
f. All share the same efficiency

d. Four-pipe fan coil units

Select the system that consumes the smallest or no floor area inside the building (no mechanical rooms) is:
a. Packaged units (also known as DX units)
b. Any central air system with a boiler and chiller as the central source of heating and cooling
c. Any water system with a boiler and chiller as the central source of heating and cooling

a. Packaged units (also known as DX units)

To save energy by exchanging heat and moisture between fresh air and exhaust air, the appropriate heat recovery unit to use is:
a. Plate-to-plate units
b. Enthalpy wheels (desiccant wheels)
c. Energy wheel
d. Heat pipes
e. Heat pumps

b. Enthalpy wheels (desiccant wheels)

Which of the following is a heat rejection device (rejects heat to the outdoors)?
A. Air-cooled chiller
B. Cooling tower
C. Water-cooled chiller
D. Air handling units
E. A and B
F. A and C
G. C and D

E. A and B

In the closed loop heat pump systems, the heat pumps operate as:
a. Air-to-air heat pumps all year
b. Water-to-air heat pumps all year
c. Air-to-water heat pumps all year
d. Water-to-water pumps all year
e. Air-to-water in the cooling mode and water-to-air in the heating mode

e. Air-to-water in the cooling mode and water-to-air in the heating mode

Furnaces are typically used to provide heating for single-family homes. Furnaces generate:
a. Hot water
b. Steam
c. Hot air

c. Hot air

In the heating mode, VAV boxes supply the required rate of heating by controlling:
a. Air flow by means of the motorized damper inside of the VAV box
b. Flow of hot water into the reheat coil
c. Both of the above

c. Both of the above

The cooling tower is considered to be a ......................................................................................[a] heat exchanger, [b] heat pump, [c] heat rejection device

[c] heat rejection device

The unit heater is considered to be a ..........................................................................................[a] heat exchanger, [b] heat pump, [c] heat rejection device

[a] heat exchanger

Fan coil terminals and unit ventilators are considered to be ......................................................
[a] heat exchanger, [b] heat pump, [c] heat rejection device

[a] heat exchanger

The heating and cooling coils inside air handling units are considered to be ............................
[a] heat exchangers, [b] heat pumps, [c] heat rejection devices

[a] heat exchangers

Fan coil terminals (units) are terminal units in a water system, they .........................................[a] can provide ventilation, [b] cannot provide ventilation

[b] cannot provide ventilation

Unit ventilators are terminal units in a water system, they..........................................................
[a] can provide ventilation, [b] cannot provide ventilation

[a] can provide ventilation

Passive chilled beams are terminal units in a (four-pipe) water system, they can provide ........
[a] cooling only, [b] heating only, [c] simultaneous heating and cooling

[c] simultaneous heating and cooling