The document discusses a new methodology for assessing how facades impact thermal comfort using detailed dynamic simulations. It involves:
1) Calculating solar radiation on body parts using Radiance raytracing and accounting for complex fenestration systems.
2) Using the Physiology model (PhySCo) to calculate the body's thermo-physiological response and transient thermal sensation/comfort.
3) Example calculations are shown for different shading systems in Bolzano, Italy, looking at solar load, sensation, and comfort over time and annually.
Exploring the Future Potential of AI-Enabled Smartphone Processors
Sabine Hoffmann, Technische Universität Kaiserslautern (DE) “How facades impact thermal comfort – a new methodology for assessment“
1. The Future Envelope 12 final event 20-21 May 2019, Bolzano
How facades impact thermal comfort :
A new methodology for assessment
Prof. Dr.-Ing. Sabine Hoffmann
TU Kaiserslautern
2. The Future Envelope 12 final event 20-21 May 2019, Bolzano
• Future envelopes need to
focus on energy reduction
and users’ comfort
• Daylight and solar radiation
are main influences on visual
and thermal comfort
• Trades-offs are often
necessary
• Solar and light management
is becoming more and more
important
• Detailed assessment
methods are necessary
Introduction
2
3. The Future Envelope 12 final event 20-21 May 2019, Bolzano
What is new?
• Variable occupant positions in the space, complex room geometries
• Detailed calculation of solar radiation on body parts
– Radiance raytracing calculations
– BSDF for complex fenestration systems (shading systems)
• Transient calculation of the body’s thermo-physiological reaction
– PhySCo: Physiology model
• Transient calculation of thermal sensation and thermal comfort
– PhySCo: Sensation and Comfort model
A new methodology for assessment
3
4. The Future Envelope 12 final event 20-21 May 2019, Bolzano
Transient assessment of thermal comfort
PhySCo
Radiance
4
Building
Simulation
5. The Future Envelope 12 final event 20-21 May 2019, BolzanoThe Future Envelope 12 final event 20-21 May 2019, Bolzano
Calculating solar load with Radiance
5
Continuous sky Discretized sky
Geometry of room and manikin
Solar load on body
• Complex room geometry possible
• Varying postures and positions
6. The Future Envelope 12 final event 20-21 May 2019, BolzanoThe Future Envelope 12 final event 20-21 May 2019, Bolzano
Possible workflows
Conventional raytracing The Three-Phase Method with BSDF
BSDF
6
• “Point in time”
• Macro systems
• Annual calculations
• Micro systems
7. The Future Envelope 12 final event 20-21 May 2019, Bolzano
PhySCo: Physiology, sensation, and comfort
Skin & Core
temperatures
Local Solar Load (W)
Local + Overall
Sensation
Overall
Comfort
T_air (°C)
V_air (m/s)
RH (%)
Local MRT (°C)
Metabolic Rate (met)
Clothing type (clo)
Physiology
7
Sensation Comfort
Local
Comfort
8. The Future Envelope 12 final event 20-21 May 2019, Bolzano
1
2 6
8
10
4
12
14
1615
13
11
9
7
5
3
Shortwave
Radiation
Longwave
Radiation
Respiration
Thermoregulation
Vasodilation
Vasoconstriction
Convection
Evaporation
Physiology
Zhang 2003
Sensation and Comfort
• no-opposite sensation
• opposite sensation
• mean based -> acceptance
• complaint driven -> discomfort
θi,j
8
Stolwijk, Tanabe
PhySCo: Physiology, sensation, and comfort
9. The Future Envelope 12 final event 20-21 May 2019, Bolzano
Example calculations:
Thermal comfort with shading systems
under clear sky conditions
in Bolzano, Italy
9
10. The Future Envelope 12 final event 20-21 May 2019, Bolzano
Shading systems
1. No shade (clear glass Tvis = Tsol = 60 %)
2. Venetian blinds 0°
3. Venetian blinds 45°
4. Honeycomb
5. Prismatic glass
2
3
4
5
1
10
Reference case
11. The Future Envelope 12 final event 20-21 May 2019, Bolzano
Jun 21
Sep 23Mar 20
Dec 22
Sun position
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12. The Future Envelope 12 final event 20-21 May 2019, Bolzano
0
50
100
150
200
250
2165 2285 2405 2525 2645 2765 2885
Solarload[W]
Time [hr]
0
50
100
150
200
250
0 120 240 360 480 600 720
Solarload[W]
Time [hr]
0
50
100
150
200
250
1445 1565 1685 1805 1925 2045 2165
Solarload[W]
Time [hr]
0
50
100
150
200
250
725 845 965 1085 1205 1325 1445
Solarload[W]
Time [hr]
8:00 10:00 12:00 14:00 16:00 18:00
8:00 10:00 12:00 14:00 16:00 18:00
8:00 10:00 12:00 14:00 16:00 18:00
8:00 10:00 12:00 14:00 16:00 18:00
Solar load on all body segments
Mar 20
Jun 21Dec 22
Sep 23
12
16. The Future Envelope 12 final event 20-21 May 2019, Bolzano
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Conclusion
• Solar radiation is a main influence on thermal comfort
-> PMV is not sufficient to assess thermal comfort
-> Importance of (dynamic) shading systems
• Radiance can be used for detailed solar load calculations on
the human body
• Detailed calculation methods are available (PhySCo)
-> Human-centered assessment method
17. The Future Envelope 12 final event 20-21 May 2019, Bolzano
• PhySCo in transient building simulation to control and
optimize dynamic shading systems
• Validation of results through human subject tests in
the Living Lab smart office space
Outlook
17