Form on the Air Temperature Based on Mobile Measurement: a Case - - PowerPoint PPT Presentation
Research on the Influence of Block Function and Form on the Air Temperature Based on Mobile Measurement: a Case Study in Wuhan By: Xu Huahua Email: 1049864796@qq.com CONTENTS 1 Introduction 2 Methods 3 Results and discussion 4
Research on the Influence of Block Function and Form on the Air Temperature Based on Mobile Measurement: a Case Study in Wuhan
By: Xu Huahua Email: 1049864796@qq.com
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In recent years, urban climate change has received more and more attention. The research on the urban climate are mostly fource on those topics, and the study subjects are from a single building to a entire city. The study methods include numerical simulation, wind tunnel, remote sensing, field measurement. In this paper, we research the influence of the form and function of different blocks on the air temperature in the downtown area of Wuhan.
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Scale Area Topics Tools urban ≥500 km2 urban climate map, urban heat island, transformation and chemistry of urban pollution WRF/MM5 + CMAQ regional 10-100 km2 the influence of urban morphology and land use on the thermal and wind environment, anthropogenic heat GIS + RS block ≤1 km2 the influence of building height, building area density, frontal area index, height-to-width ratio, SVF, on the thermal environment CFD building 1000 m2 heat emission of a single building CFD, wind tunnel
Table 01: Research topics, tools of different scales in urban climate
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We selected five blocks(Z-01~Z-05) in Wuhan, including business zone, industry zone and residential zone. The measurement started at July 23 and end at July 30 in 2016, each day we measure the air temperature three times at 5:30~6:30, 14:00~15:00, 20:00~21:00
Z-01 Z-02 Z-03 Z-04 Z-05 Fixed point
This photo comes from Hiroki YOKOYAMA, etc, Study of Mobile Measurement for Detailed Temperature Distribution in a High-Density Urban Area in Tokyo2016
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Method Instrument Item Specification Recor
interval Fixed ed Thermo-hygrometer Air temperature、Relative humidity Accuracy：0.1℃；±0.2℃； Rang：-35~80℃ 10s Weather station Wind speed Accuracy：0.01m/s；±3%； Rang：0.1~30 m/s 20s Wind direction — 20s Solar radiation — — Mobile Thermo-hygrometer Air temperature、Relative humidity Accuracy：0.1℃；±0.2℃； Rang：-35~80℃ 10s GPS Latitude, Longitude Accuracy：2.2m 10s Date Air temper eratu ture（℃） Relative humidity (%) weather Wind speed （m/s m/s） Wind direction Max Min 7/23 35 29 53~75 sunny 1-3 south 7/24 36 28 50~90 Sunny-cloudy 1-4 south 7/26 37 27 50~95 sunny 0-3 south 7/27 37 27 47~94 sunny 0-3 south 7/28 38 28 52-81 sunny 0-3
38 28 53~85 sunny 0-3
Table 03: the weather condition of Wuhan during the measurement
Wuhan is one of ten hottest cities in China, and nearly one-third of the urban area is the lake surface.
Why Wuhan?
In the last decade, the month with the highest monthly average temperature was July (33.4℃).
Why July?
The hot summer start in late June and end in Mid-October, last fot 135 days.
Why summer
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Z-01: Business Z-03: Residential
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Z-02: Industry
zone area(km2) building floor building density(%) plot ratio 5.29 6-54 56.4 3.32 zone area(km2) building floor building density(%) plot ratio 2.21 18-32 34.4 4.87 zone area(km2) building floor building density(%) plot ratio 21.316 1-3 34.1 0.72
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Z-04: Residential
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Z-05: Residential
zone area(km2) building floor building density(%) plot ratio 4.918 3-6 31.5 1.46 zone area(km2) building floor building density(%) plot ratio 8.013 6-24 27.5 1.57
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Correction for the air temperature: according to the daily variation of air temperature, we want to exclude the influence of temperature rise caused by solar radiation. We use the temperature rise of the fixed point to express the effect of solar radiation on the air temperature, and then subtract the fixed temperature from the data measured by the moving point. The formula is as above:
Z-01: 5:30~6:30 Z-01: 14:00~15:00 Z-01: 20:00~21:00
Z-01 Business zone: 1) 5:30~6:30, The highest temperature appears on the left side of the site where there are mainly high-rise residences. 2) 14:00~15:00, There are two parts of high temperature, The traffic volume of these two roads is very large, and the vehicles cause an increase in artificial heat emission, which makes the air temperature rising. 3) 20:00~21:00, The highest temperature appears on the north-east side of the site where there are mainly shopping malls.
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Shopping mall High-rise residences
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Z-02: 5:30~6:30 Z-02: 14:00~15:00 Z-02: 20:00~21:00
Z-02 Industry zone: 1) The air temperature in west of the site is always higher than that in the east, no matter in which time, the reason is, at first, the traffic volume in the west is much bigger than the east, and the function is mainly business and industry in the west, so the artificial heat emission is much more than the east. Secondary, Compared with the west, the height and density of buildings in the east are smaller, which is more conducive to the heat dissipation.
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Z-03: 5:30~6:30 Z-03: 14:00~15:00 Z-03: 20:00~21:00
Z-03 High-rise residential zone: 1) The highest temperature appears on the south-east side of the site which is adjacent to the elevated road, and there are high-rise residences over 100m. 2) Another high temperature appears on the mid-east of the site at 14:00~15:00, that’s because there are high-rise building with shopping mall and office function. Shopping mall &
High-rise residences
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Z-04: 5:30~6:30 Z-04: 14:00~15:00 Z-04: 20:00~21:00
Z-04 Low-rise residential zone: 1) The maximum variation of the air temperature is 0.6 ℃ in the three schedules, and the lowest temperature appears on the mid-east of the site which has a small building density and is adjacent to a park and a river. 2) The south of the site has a high air temperature at 14:00~15:00 and 20:00~21:00, because the traffic volume is very big at that time.
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Z-05: 5:30~6:30 Z-05: 14:00~15:00 Z-05: 20:00~21:00
Z-05 Waterfront high-rise residential zone : 1) Obviously, the air temperature on the waterfront side is much lower than that in the inland, espacially in the afternoon, the maximum variation of air temperature is 3.9 ℃. 2) The air temperatures in places with higher building densities and heights are also significantly higher than those with low building densities and heights.
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25.0 26.0 27.0 28.0 29.0 30.0 31.0 32.0 33.0 34.0 35.0 36.0 37.0 38.0 39.0 40.0 41.0 42.0
5:40 5:42 5:44 5:46 5:48 5:50 5:52 5:54 5:56 5:58 6:00 6:02 6:04 6:06 6:08 6:10 6:12 6:14 6:16 6:18 6:20 6:22 6:24 6:26 6:28 6:30 14:01 14:03 14:05 14:07 14:09 14:11 14:13 14:15 14:17 14:19 14:21 14:23 14:25 14:27 14:29 14:31 14:33 14:35 14:37 14:39 14:41 14:43 14:45 14:47 14:49 14:51 14:53 14:55 14:57 14:59 15:01 15:03 15:05 20:01 20:03 20:05 20:07 20:09 20:11 20:13 20:15 20:17 20:19 20:21 20:23 20:25 20:27 20:29 20:31 20:33 20:35 20:37 20:39 20:41 20:43 20:45 20:47 20:49 20:51 20:53 20:55 20:57 20:59
T
air（℃）
江汉路商业
红钢城工业 后湖高层住区 红钢城多层住区 南湖高层滨水住区Z-01 Z-02 Z-03 Z-04 Z-05
The variation of air temperature of five zones: In order to visually compare the effects of different plots on the function of the air temperature, we plot the temperature profiles
1. The maximum daily variation of air temperature appears in Z-05 (waterfront high-rise residential zone, 3.9℃), and the minimum variation appears in Z-04(low-rise residential zone, 0.5℃). 2. In the morning and everning, the air temperature of Z-05 is significantly lower than other zones. The same situation appears
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The variation of air temperature of five zones: 3. Due to the cooling effect of the water, the temperature of Z-05 drops significantly at 20:00~21:00; the air temperature of Z- 03 is the highest, and the distribution is concentrated. That’s because the heat emission come from the air conditioning is greatly increased at this time. 4. The temperature variation of Z-02 is large(about 3.2 ℃) at 14:00~15:00, and is concentrated on the west and south side of the site which is the main road of the city. The main reason is that the industry and traffic heat emission are concentrated on this place, and the building height and density are large here, resulting in a heat accumulation and difficulty in heat dissipation.
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In this paper, we obtained the air temperature of different blocks in Wuhan by mobile measurement, and visualizad and analyzed the data to study the influence of the function and morphology of urban blocks on the temporal and spatial distribution characteristics of air temperature. 1. Urban morphologies, such as building height, building density, floor area ratio and other factors will have a greater impact on air temperature. Generally, the place with a higher building height and density have a higher air temperature. 2. Urban functions, such as commercial, industrial, residential, etc., affect the temporal distribution of air temperature through the amount and time of artificial heat emission. On the
3. In addition, rivers and lakes have obvious cooling effects on waterfront zone, especially in the absence of solar radiation, such as morning and evening.