Urban Form Effect on Outdoor Thermal Environment Case Study of - - PowerPoint PPT Presentation

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10th International Conference on Urban Climate/ 14th Symposium on the Urban Environment Presentation Urban Form Effect on Outdoor Thermal Environment Case Study of Traditional Arcade-Street Neighborhood in Hot Humid Zone Shi Yin, Werner Lang,

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

10th International Conference on Urban Climate/ 14th Symposium on the Urban Environment Presentation

Urban Form Effect on Outdoor Thermal Environment

Shi Yin, Werner Lang, Yiqiang Xiao 10.08.2018 New York Case Study of Traditional Arcade-Street Neighborhood in Hot Humid Zone

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

Introduction BACKGROUND Traditional Neighborhood 1900s

Compact and Uniform Layout
Humanity Scale
Shading Facility (Grey and

Green Infrastructure)

Modern Neighborhood 2000s

High Rise Building
Over Wide Street
High Sky Explosion

Guangzhou

LCZ classification map of Guangzhou

http://geopedia.world/#T4_L107_x12622485.993643802_y2641625.479021549_s11_b17

Legend Modern area Guangzhou Zhujiang New Town Traditional area Guangzhou Enning Road

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

What we can learn from the strategy

adopted in such local neighborhoods to respond their climate, and furthermore, how apply the historical experience on current urban form design to improve the pedestrian thermal comfort?

RESEARCH ISSUE

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

Traditional Neighborhood in South China CASE STUDY

Block Division Canyon Case Arcade Street Alley Neighborhood Da=3-9m H/W=1-4 A=30-120m B=25-30m H=7-21m Scale Dp=9-21m H/W=0.7-1.2 Type

A B

Taishan Guangzhou Shantou Xiamen

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

Street Canyon Survey and Measurement Block Division Neighborhood Layout Type and Aspect-ratio HYPOTHESIS & FRAMEWORK Type and Scale In Traditional Arcade-street Neighborhood Climate Responding Simplified Spatial Model Simplified Spatial Model Pedestrian Thermal Comfort

Correlate influence of

neighborhood layout and street canyon on urban climatology

Combine the layout and

canyon according its climate adaptive code in design perspective

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

Spatial Model METHODOLOGY

Set Volume: 120mx120mx12m Set depth of Building: 30m Set Context: Surrounded Arcade Street (W=12m) Variant: Block Division (Proportion, A/B)

| Neighborhood Design Level | Canyon Design Level | Pedestrian Thermal Comfort

Set height of Building: 12m Variant: Canyon Type/ Aspect Ratio Interval: 3m

12m

Analysis: Pedestrian Area

A B H W

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

CANYON LAYOUT

A/B=4.00 A/B=2.00 A/B=1.33 A/B=1.00 A/B=0.75 A/B=0.50 A/B=0.25

ANALYSIS

Aspect Ratio Canyon Type Orientation Layout Type Thermal Comfort In Summer Daytime H/W=4.00/2.00/1.33 Dp=3m/6m/9m H/W=1.33/1.00/0.80 Da=9m/12m/15m

RESULT

Impact of Urban Form On OTC

Correlation Analysis METHODOLOGY

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

Microclimate Model METHODOLOGY Model

Envi-met V4.3.1 Domain: 300x300x30m Net size: 3x3x2m Duration: 4am-8pm Boundary Condition: from measurement

Alley Dp=3m Arcade Da=12m Receptors

In orthogonal Axis Every 9m on each side Only in pedestrian area

Assessment

Pedestrian Thermal Comfort Physiological Equivalent Temperature (PET). Calculate by Biomet Thermal comfort range:

（Slight Cool）（Comfort） 1 （Slight Warm） 2 （Warm） 3 （Hot） 4 （Very hot） PET Taiwan <26 26-30 30-34 34-38 38-42 42 (Lin, Matzarakis et al. 2008)

Time percentage of under Warm feeling Wind Environment

Boundary Condition

In Situ measurement, 4 days, two neighborhoods, Xiamen, Guangzhou Ta, Tg, V, rH recorded in 1.5m height Local weather data in measurement area:

4 8 12 16 20 24 26 28 30 32 34 36 38 40 2017.07.24@XM

Ta(OC)

4 8 12 16 20 24 2017.07.25@XM 40 45 50 55 60 65 70 75 80 85 90 95

rH(%)

4 8 12 16 20 24 26 28 30 32 34 36 38 40

Ta(oC)

2017.07.30@GZ 4 8 12 16 20 24 Ta rH Ta rH 2017.08.06@GZ 40 45 50 55 60 65 70 75 80 85 90 95

rH(%)

Guangzhou Xiamen

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

Validation

XIAMEN Date: 24.07.2017, 8am-8pm 25.07.2017, 8am-8pm GUANGZHOU Date: 30.07.2017, 8am-8pm 06.08.2017, 8am-8pm In Situ Measurement Validation of Simplified Model

RESULT

Simplified Scenario (Envi-met)

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 A1N A1 S A2 N A2 S A4 P

RMSE

0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00 A1N A1 S A2 N A2 S A4 P

R2

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 A1E A1W TN TS P2

RMSE

Ta RH Tmrt PET 0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00 A1E A1W TN TS P2

R2

Ta RH Tmrt PET 0.86 0.84 0.63 0.71 Ta RH Tmrt PET 0.77 2.95 6.58 3.45 Ta RH Tmrt PET 0.82 0.87 0.64 0.76 Ta RH Tmrt PET 0.86 1.89 5.82 2.93

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

Alley Scenario RESULT

40% 45% 50% 55% 60% 65% 70% 75% 80% 85% 1 2 3 4 5 6 7

Proportion of Thermal Stress (<Warm|2, 38℃) in ALLEY

AL3 AL6 AL9 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 1 2 3 4 5 6 7

Wind in Alley (m/s)

AL3 AL6 AL9

Better thermal comfort in south-north oriented alley
Thermal comfort improved with decreasing W-E oriented alley
Wind decreased by porosity increasing

PET at 16:00

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

40% 45% 50% 55% 60% 65% 70% 75% 80% 85% 1 2 3 4 5 6 7

Proportion of Thermal Stress (<Warm|2, 38℃) in Arcade

AR9 AR12 AR15 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 1 2 3 4 5 6 7

Wind in Arcade (m/s)

AR9 AR12 AR15

Arcade Scenario RESULT PET at 16:00

Pedestrian thermal comfort deteriorate with adding S-N oriented street
Wind decreased by porosity increasing

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

Different Canyon Type RESULT

WE NS

40% 45% 50% 55% 60% 65% 70% 75% 80% 85% 90% 1 2 3 4 5 6 7

Thermal Stress in Different Oriented Alley

AL3-NS AL3-WE AL6-NS AL6-WE AL9-NS AL9-WE 40% 45% 50% 55% 60% 65% 70% 75% 80% 85% 90% 1 2 3 4 5 6 7

Thermal Stress in Different Oriented Arcade

AR9-NS AR9-WE AR12-NS AR12-WE AR15-NS AR15-WE 40% 45% 50% 55% 60% 65% 70% 75% 80% 1 2 3 4 5 6 7

Proportion of Thermal Stress (<Warm|2, 38℃) in D=9m

AL9 AR9 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 1 2 3 4 5 6 7

Wind in D=9m

AL9 AR9

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Urban Form Effect on Outdoor Thermal Environment | Shi Yin

CONCLUSION

Common

Wind decreased by porosity increasing;
The value of A/B between 0.75-0.5 achieve better thermal comfort in both

canyon type; Difference

Neighborhood layout effect the thermal comfort in alley street significantly;
Better thermal comfort for pedestrian in W-E oriented Arcade street

Further research

Canyon with greenery respond varying neighborhood layout
Influence of wind direction
Combination different canyon type in different oriented street

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