4.492 Daylighting in Buildings Class01 · “Introduction to Architectural Science” by Szokolay:...
Transcript of 4.492 Daylighting in Buildings Class01 · “Introduction to Architectural Science” by Szokolay:...
Passive controls
Passive solar heatingDirect gain and control of heat flow control of sunlight penetration
good thermal quality of window (thermal insulation, thermal bridges)
proper orientation
other factors
Low-Eplacement for
warm climates
Low-Eplacement for cold climates
Passive controls
Passive solar heatingDirect gain and control of heat flow
Heat storage wall (transparent insulation) stores heat in wall mass
adds to direct gain
Image by MIT OCW.
Passive controls
Passive solar heatingDirect gain and control of heat flow
Heat storage wall stores heat in wall mass
adds to direct gain
MASONARY
BLACK
GLASS
SUMMERWINTER
Trombe wall
Image by MIT OCW.
Passive controls
Passive solar heatingDirect gain and control of heat flow
Heat storage wall
Greenhouse heat collection during the day
buffer during the night
Winter
Summer
Image by MIT OCW.
Passive controls
Passive solar heatingDirect gain and control of heat flow
Heat storage wall
Greenhouse heat collection during the day
buffer during the night
design constraints
draw-backs
Passive controlsPassive solar heating
Control Potential Zone limit temperature(s) achievable with passive control:
Dv x A x η = q x (Ti – To)
report on psychrometric chart and determine CPZ
15
11.5
108.5
g/kg
5
050403020
22.3 24.8 27.3 C
40%
30%
20%
10%
°
ET
·40
SET35
·
SET
·30ET
·25
ET
·20
Image by MIT OCW.
Passive controls
Passive solar heating
Thermal mass
Passive controls
Jacobs House II in Wisconsin (Frank Lloyd Wright)
Photographs and floor plans removed due to copyright restrictions.
Passive controls
Theuer House in Phoenix AZ (William Bruder)
Photograph and floor plan removed due to copyright restrictions.
Passive controls
Passive solar heating
Thermal massmass distribution
continuous occupation
cold or hot-dry climates
specific mass
night ventilation
35
30
25
20
152 3 4 5 6 7
Tem
pera
ture
(oC
)
Date in August
Day Ventilation
Night Ventilation
Outside oTImage by MIT OCW.
Passive controls
Passive solar heating
Thermal mass
Air movementheat dissipation
cross-ventilation or fans
apparent cooling effect:
dT = 6v - 1.6v2
Stationarywarm air
Two openings
Cross-ventilation
One opening
Chimney
Two openingsTwo openings
Cross-ventilationCross-ventilation
One openingOne opening
ChimneyChimney
-10oC 500
5
10
15
20
25
30
403020100g/kg
Boundaries of the Control Potential Zone
Solid: with 1 m/s velocityDotted: with 1.5 m/s
Image by MIT OCW.
Passive controls
Passive solar heating
Thermal mass
Air movement
Evaporative cooling
Sump with float valve for make-up water
Fibrous material pade.g. wood shavingsin cheese cloth
Perforated drip pipe
Pump Motor
Fan
Image by MIT OCW.
Thermal balance
Equilibrium of heat gains and lossesQi + Qc + Qs + Qv + Qe = 0
Thermal balance
Qi + Qc + Qs + Qv + Qe = 0Qi = internal gain (±)
Internal GainsHeat Balance: QF + QV + QS + QI + QE
Image by MIT OCW.
Thermal balance
Qi + Qc + Qs + Qv + Qe = 0Qi = internal gain (±)
Qc = conduction gain (±)
Fabric Gains
Approx.Outside AirTemp 30O
Summer Sun
Heat Balance: QF + QV + QS + QI + QE
Image by MIT OCW.
Thermal balance
Qi + Qc + Qs + Qv + Qe = 0Qi = internal gain (±)
Qc = conduction gain (±)
Qs = solar gain (+)
Solar Gains
Approx.Outside AirTemp 12O
Winter Sun
Heat Balance: QF + QV + QS + QI + QE
Image by MIT OCW.
Thermal balance
Qi + Qc + Qs + Qv + Qe = 0Qi = internal gain (±)
Qc = conduction gain (±)
Qs = solar gain (+)
Qv = ventilation gain (±)
Ventilation Gains
Heat Balance: QF + QV + QS + QI + QE
Image by MIT OCW.
Thermal balance
Qi + Qc + Qs + Qv + Qe = 0Qi = internal gain (±)
Qc = conduction gain (±)
Qs = solar gain (+)
Qv = ventilation gain (±)
Qe = evaporative loss (-)
Evaporative GainsHeat Balance: QF + QV + QS + QI + QE
Image by MIT OCW.
Thermal balance
Qi + Qc + Qs + Qv + Qe = 0 for design projectQi = internal gain (+) = secondary heat sources + primary heating
Qc = conduction gain (-)
Qs = solar gain (+)
Qv = ventilation gain (-)
Qe = evaporative loss (-) ≈ 0
determine active ("primary") heating component in Qi
Passive gains/losses(for early March)
Integrated approach: new classroom at MIT
Criteria and risks for site
envelope
materials
…
Passive controls, Thermal Balance
Reading assignment from Textbook:“Introduction to Architectural Science” by Szokolay: § 1.4 (Intro) + § 1.5.1 - 1.5.2
Additional readings relevant to lecture topics:"How Buildings Work" by Allen: Chap 9 + pp. 73 - 77 in Chap 10
"Heating Cooling Lighting" by Lechner: Chaps 7 + 10