Numerical Investigation on the Urban Heat Island Effect by Using a Porous Media Model

Tingzhen Ming,Nyuk Hien Wong,Shengnan Lian,Renaud De Richter,Yueping Fang,Tianhao Shi,Yongjia Wu,Chong Peng

doi:10.3390/en14154681

Abstract

The urban heat island (UHI) effect resulted from urbanization as well as industrialization has become a major environmental problem. UHI effect aggravates global warming and endangers human health. Thus, mitigating the UHI effect has become a primary task to address these challenges. This paper verifies the feasibility of a three-dimensional turbulent porous media model. Using this model, the authors simulate the urban canopy wind-heat environment. The temperature and flow field over a city with a concentric circular structure are presented. The impact of three factors (i.e., anthropogenic heat, ambient crosswind speed, and porosity in the central area) on turbulent flow and heat transfer in the central business district of a simplified city model with a concentric circular structure were analyzed. It is found that the three-dimensional turbulent porous media model is suitable for estimating the UHI effect. The UHI effect could be mitigated by reducing the artificial heat and improving the porosity of the central city area.

Highlights

With global urbanization increasing, the rapid change in the structure of modern cities and human activities’ increasing have made urban heat islands (UHI) more and more serious. [1]
The UHI intensity can increase rapidly with the city size and a maximum intensity of 12 K was observed in Lodz (Poland) and Mexico City (Mexico) [2]
This study focuses on the effect of artificial heat on the UHI effect

Summary

Introduction

The rapid change in the structure of modern cities (e.g., high-density buildings) and human activities’ increasing (e.g., heavy urban traffic) have made urban heat islands (UHI) more and more serious. [1]. The rapid change in the structure of modern cities (e.g., high-density buildings) and human activities’ increasing (e.g., heavy urban traffic) have made urban heat islands (UHI) more and more serious. The UHI intensity can increase rapidly with the city size and a maximum intensity of 12 K was observed in Lodz (Poland) and Mexico City (Mexico) [2]. Environmental problems in cities (i.e., reduced diffusion capacity of waste heat and pollution) have become the primary concern for city dwellers. Manley first proposed the concept of the UHI in 1958 [3]. Since the concept was proposed, many scholars have investigated UHI phenomena using field measurement methods, such as meteorological data and fixed-point, mobile, and infrared thermal measurements. Mathew and Kaul [4]

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Discussion

Conclusion