Mechanical Systems

Question 1

The energy produced per unit of surface area per hour by a seated person at rest

Answer 1

1 met (metabolic unit) = 18.4 Btu/hr-ft^2

Question 2

Factors: air temperature, humidity, air movement, surface temperature, clothing, ventilation

Answer 2

Factors in thermal comfort

Question 3

Relative humidity

Answer 3

Percent moisture in the air : maximum amount of moisture the air can hold at a given temperature without condensing

Question 4

emissivity

Answer 4

measure of an object’s ability to absorb and radiate heat (emittance: ratio of the radiation emitted by an object at a given temperature to the radiation emitted by a black body at the same temperature)

Question 5

mean radiant temperature (MRT)

Answer 5

a weighted average of all surface temperatures in a room and the angle of exposure of the occupant to these and any sunlight present

Question 6

operative temperature

Answer 6

average of air temperature of a space and the MRT of the space ;; can be measured using a black globe thermometer