1. Opportunities in variability of indoor temperature
Effect of spatial transitions on thermal comfort perception of occupants in closed office spaces
Opportunities in variability of indoor temperature
Introduction
Background
Research Question and Hypothesis
Research Methods
Findings / Data
Discussion
Conclusions
Further research
7LS1M0 BPS research project A
Date:
4 May 2018
Student:
J.J. (Arjan) Kraakman
Supervisors:
dr. A.K. (Asit) Mishra
dr.ir. M.G.L.C. (Marcel) Loomans

2. Introduction Limiting global warming <1.5 ⁰C
EU low-carbon economy in 2050
100% renewable energy sources
Constant  non-constant energy supply
Variability in indoor conditions
Ensuring comfort perception
Paris Agreement
80% reduction of Greenhouse gasses 1990
Office space rapidly evolves like flexible working
Introduction

3. 330 North Wabash (IBM building)
Wind city
330 North Wabash (IBM building)
Introduction

4. Background Primarily focused steady frame
Adaptation time and thermal perception1
Magnitude (∆T) of the temperature jump2
Not affected within ±3 ⁰C1
Primarily focused on occupants in a steady frame
Looked at adaptation time and thermal perception immediately following transitions
Effect of spatial transition on thermal perception depends on the magnitude of the temperature jump
At comfort level ± 2 degrees and warm of cold already at 1 degrees
Thermal perception is not significantly affected when the temperature difference across which the transition takes places keeps within ±3 degrees
[1] Mishra et al, 2016
[2] Palma & Stevenson, 2015
Figure 1 Relaxed thermal comfort requirements for transition spaces. (Mishra et al., 2016)
Background

5. Research Question Hypothesis
Movement across what range of inter-zone temperature difference does not impact occupant thermal perception?
Hypothesis
Temperature differences of 3 ℃, or less, between regular use and transitional spaces does not influence thermal sensation to a significant degree.
Research Question

6. Research Methods 6 occupants Room level control of indoor temperature
Two weeks
General comfort
End of October and end of November
Figure 4 Result comfort vote general survey Metaforum level 5
Figure 2 Floorplan MetaForum level 5
Figure 3 thermostat rooms
Research Methods

7. Instruments Questionnaire survey Time Spent out of room
Spent in room since last entry
Previous location
Temperature sensation vote (TSV)
Temperature comfort vote (TCV)
Measuring parameters
Wireless sensors on desks
Wireless sensors hallway (1,7 m)
Thermostat sensor of system
Point-in-time survey
Import questions: Time until fill in after transition, location before and TSV
Figure 6 position wireless T sensor and climate pole
Figure 5 Point-in-time survey
Research Methods

8. Results 142 usable responses
Temperature samples not significantly differ (p < 0.001)
Step change responses
Tair,BMS  77
Δ Tsensor  103
Did not significantly differ between the two periods of measurements
Delta Tdesk – Thallway
Delta TBMS – Thallway
Results

9. Results
Results

10. Results
Results

11. Results p value = 0.000 p value = 0.085 Hallway Hallway
TSV vs Δ Tsensor  weak (positive), non-significant
TSV vs Δ TBMS  weak (positive), significant
Figure 8 Section office MetaForm with hallway
Figure 7 Section office MetaForm with hallway
p value = 0.000
p value = 0.085
Results

12. Discussion Hypothesis not rejected with Tair,desk-sensor
Indicate that effect of transitions across temperature difference ±2 ℃, if any, on thermal perception is to short to affect perceptions significantly.
Figure 9 Section office MetaForm with hallway
Discussion

13. Discussion Most step changes within ±2 ℃ Small data sample
Cooler temperature for Tair,BMS
TSV similar to Tair,BMS and Tair,hallway
TSV correlated to Tair,hallway  museum study3
Important limitation of the study
Mean values of 21.8 vs 22.5 ⁰C
Distance to hallway
Within the last 20 minutes TVS correlate outdoor temp
[3] Mishra et al, 2016
Figure 9 Section office MetaForm with hallway
Discussion

14. Conclusion Δ Tair,desk-sensor ±2 ℃  TSV is negligibly impacted by ∆T
Promising results for climate chamber studies
Thermal zoning
Energy usage
Conclusion

15. Further research Creating larger Δ T Over other seasons
Different office building layouts
Different use patterns
Further research

16. Questions