Outdoor thermal comfort: Analyzing the impact of urban configurations on the thermal performance of street canyons in the humid subtropical climate of Sydney

دسته: , تاریخ انتشار: 22 اردیبهشت 1400تعداد بازدید: 359
قیمت محصول

رایگان

جزئیات بیشتر

انتشار

۲۰۲۱

پایگاه داده

نشریه الزویر

نوع نگارش مقاله

مقاله پژوهشی

نمایه

scopus – master journals – JCR

ایمپکت فاکتور

۴٫۲۷۶ در سال ۲۰۲۰

شاخص H_index

۲۶ در سال ۲۰۲۱

شاخص SJR

۰٫۹۰۱ در سال ۲۰۲۰

شاخص Quartile (چارک)

Q1 در سال ۲۰۲۰

مدل مفهومی

ندارد

پرسشنامه

ندارد

متغیر

ندارد

رفرنس

دارد

قوانین استفاده

خرید محصول توسط کلیه کارت های شتاب امکان پذیر است و بلافاصله پس از خرید، لینک دانلود محصول در اختیار شما قرار خواهد گرفت و هر گونه فروش در سایت های دیگر قابل پیگیری خواهد بود.

توضیحات مختصر محصول
Outdoor thermal comfort: Analyzing the impact of urban configurations on the thermal performance of street canyons in the humid subtropical climate of Sydney

فهرست مطالب مقاله:

Abstract

Abstract    The quality of outdoor space is becoming increasingly important with  the  growing rate of urbanization. Visual, acoustic, and  thermal balance degradation are  all negative im- pacts associated with  outdoor comfort in dense urban  fabrics. Urban morphology thus  needs assessment and  optimization to ensure favorable outdoor thermal comfort (OTC). This study aims to  evaluate the  thermal performance of streets in residential zones  of Liverpool,  NSW, Australia, and  tries to  improve  their comfort index  (Physiological Equivalent Temperature) to reveal optimum urban  configurations. This evaluation is done  by investigating the  following urban  design factors affecting OTC using computational simulation techniques: street orienta- tion, aspect ratio, building  typology, and  surface coverage. Our findings reveal that street canyon  orientation is the  most  influential factor (46.42%), followed by aspect ratio  (۳۰٫۵۹%). Among the influential meteorological parameters (air  temperature, wind speed, humidity and  solar  radiation), wind velocity had  the  most  significant impact on the thermal comfort of the  outdoor spaces in this  coastal region, which  typically  experiences intense airflow. The results of our analysis  can  be utilized by multiple stakeholders, allowing  them to under- stand and extract the  most vital design factors which contextually influence the  thermal com- fort  of outdoor spaces. Outdoor  thermal comfort has  a direct effect on the  health and wellbeing of occupants of outdoor spaces.

بخشی از متن مقاله:
  1. Introduction

Urban  heat Island  (UHI) phenomenon, which  refers to  the higher  temperature level in cities  than  in surrounding areas (Piselli  et al., 2018),  is a  critical problem caused by  ur- banization and  associated climate change (Akbari  et al.,

2016).  The  high  temperature in urban  areas can  increase energy  spending owing  to  a high  rate of cooling  demand, thus  increasing the  pressure on the  electricity grid during heat waves  (Pyrgou  et al., 2017).  An increase in ambient temperature  can   also   negatively affect  an   individuals’ health (Santamouris et al., 2017).  Comfort, in conjunction with  health, is being  increasingly used  to  define  wellbeing in the  built  environment (Bluyssen,  ۲۰۱۰).  There  has  thus been an  increasing interest in studies concerning outdoor comfort (Srivanit  and  Jareemit, 2020).  The  value  of well- designed open  spaces in contributing towards a high qual- ity  of  life  is  now  acknowledged more  than   ever  (Klemm et al., 2015).  Outdoor   thermal  comfort (OTC) is  one  of the   most   influential factors  which   directly impacts the perceived quality of urban  open  spaces (Zhao et al., 2018) and  thus  the  participation in outdoor activities (Lai et al.,

2014).   As  a  consequence,  thermal  comfort  in  outdoor space has recently attracted considerable attention for the sustainable design  of cities  (Emmanuel, 2016).

The effect of UHI can exacerbate in cities  with a hot and humid  climatic condition characterized  by  high  air  tem- perature, high humidity and  low wind speed levels. Humid tropical climates tend to  suffer the  consequences of heat island effect twice as much as other regions. This also holds true for  urban   environments with  humid  subtropical  cli- mates (such  as Sydney) during  the  summer. More than  ۳۳% of the  world’s  population live  in such  cities, which  cover one  of  the   five  climate classes of  Koppen’s  (Cfa:  humid subtropical climate,  Cwa:   dry-winter  humid   subtropical climate, Af: tropical rainforest climate, Am: tropical monsoon  climate, Aw: tropical savanna climate with  dry- winter characteristics). Such cities  are  exposed to hot  and humid  weather condition for a considerable period of time (Binarti  et al., 2020).  On the  other hand, long  periods of warm   weather  make   outdoor  and   semi-outdoor spaces more  favorable. People thus  prefer to  spend  their time  in open   environments,  in  the   absence  of  air-conditioning (Baruti  et al., 2019).

The  geometrical properties  of  urban   blocks  and  con- struction materials are  important factors affecting UHI (Falasca et  al.,  ۲۰۱۹; Kantzioura et  al.,  ۲۰۱۵).   Well- designed outdoor spaces and  thermally comfortable out- door  environments can  enhance public   health and  well- being  (Hendel  et al., 2017; Jiang  et al., 2019),  tourism (Ge et al., 2017),  the  use  of open  spaces, and  level  of social interactions (Huang  et al., 2019).  Studies  have  found  that people’s activities in outdoor spaces decrease in summer with  an increase in air temperature (Ta) (Lin et al., 2012). Urban outdoor areas lacking microclimatic considerations in their design  thus  tend to  be  avoided and  remain unused (Lenzholzer,  ۲۰۱۲),   due   to  the   lack  of  a  practical  and applicable design guideline for urban  planning  (Lenzholzer,

2010).

This  study   investigates  the   thermal  environment  of outdoor spaces in the  humid subtropical climate of Sydney,

 

NSW, Australia, and proposes an OTC-based urban  planning guideline  by  deploying computational  optimization  pro- cesses. This  process incorporates  the   use  of  parametric design  and  simulation techniques to  optimize the  thermal performance of  street  canyons. We evaluate the  current thermal environment of  selected case  studies and  subse- quently  optimize influential  urban   planning   factors that embody    the    micro-climatic  condition  of   the    selected location.

 

۱٫۱٫ Thermal perception in outdoor environments

 

Thermal perception  in outdoor spaces is a  complex issue that can  be  affected by climatic characteristics of regions (Indraganti, 2010).  Based  on a study  conducted in highly- dense urban  contexts, three elements: weather condition (solar   radiation,  humidity,  and   wind   speed);  personal health factors; and  psychological parameters,  affect  an individuals’ outdoor  thermal  sensation  significantly (Sharmin  and  Steemers, 2020).

Among  environmental factors,  air  Temperature is  the most  determining microclimatic factor affecting thermal sensation  (Liu  et  al.,  ۲۰۱۶; Tan  et al., 2019).   Thermal comfort  is  also  dependent on  other  climatic factors  of radiant temperature and  wind speed (Niu et al., 2015; Tan et al., 2019).  Air movement with  a  velocity   higher  than

1.5  m/s has  profound effects on the  thermal sensation of users   of  outdoor  spaces  (Ali-Toudert and   Mayer,  ۲۰۰۶; Johansson and  Emmanuel, 2006).  Besides  the   pattern  of solar  radiation, various  design  factors can  also lead  to UHI phenomena  (Ouali  et al., 2018).   Modifying  a  building’s layouts can  result in a significant difference in the  level  of thermal comfort of outdoor spaces, especially in moderate climate conditions (Ouali et al., 2020).  Many studies have investigated different strategies focusing  on OTC improve- ments, namely  ventilation (Hong and  Lin, 2015),  materials (Taleghani, 2018),  vegetation (Besir and  Cuce,  ۲۰۱۸; Zo¨lch et al., 2016)  and  water bodies  (Steeneveld et al., 2014). Besides   this,   various   geometrical  parameters  of   urban canyons, such as aspect ratio  (H/W) and  orientation affect environmental conditions such as solar access, wind status, air and surface temperature (Deng and Wong, 2020). Aspect ratio  and Street Canyon Orientation are the  most important factors  in   urban    planning   concerning outdoor  thermal comfort  (Bakarman and  Chang,  ۲۰۱۵; De and  Mukherjee,

2018; Deng  et al., 2016; Huang  and  Li,  ۲۰۱۷; Taleghani et al., 2015).  The  following  sub-section provides a  brief overview  of these two  factors, and  the  urban  surface con- dition  factor, as influencers of OTC.

نمایش بیشتر
دیدگاه های کاربران
دیدگاهتان را با ما درمیان بگذارید
تعداد دیدگاه : 0 امتیاز کلی : 0.0 توصیه خرید : 0 نفر
بر اساس 0 خرید
0
0
0
0
0

هیچ دیدگاهی برای این محصول نوشته نشده است.

لطفا پیش از ارسال نظر، خلاصه قوانین زیر را مطالعه کنید: فارسی بنویسید و از کیبورد فارسی استفاده کنید. بهتر است از فضای خالی (Space) بیش‌از‌حدِ معمول، شکلک یا ایموجی استفاده نکنید و از کشیدن حروف یا کلمات با صفحه‌کلید بپرهیزید. نظرات خود را براساس تجربه و استفاده‌ی عملی و با دقت به نکات فنی ارسال کنید؛ بدون تعصب به محصول خاص، مزایا و معایب را بازگو کنید و بهتر است از ارسال نظرات چندکلمه‌‌ای خودداری کنید.  

اولین کسی باشید که دیدگاهی می نویسد “Outdoor thermal comfort: Analyzing the impact of urban configurations on the thermal performance of street canyons in the humid subtropical climate of Sydney”

نشانی ایمیل شما منتشر نخواهد شد. بخش‌های موردنیاز علامت‌گذاری شده‌اند *

قیمت محصول

رایگان