Conference Agenda

Overview and details of the sessions of this conference. Please select a date or location to show only sessions at that day or location. Please select a single session for detailed view (with abstracts and downloads if available).

 
Session Overview
Session
4ST/5: Science & Technology
Time:
Tuesday, 11/Dec/2018:
9:30am - 10:30am

Session Chair: Dr. Christopher James Whitman
Location: LT5
Lecture Theatre 5, 2/F, Yasumoto International Academic Park, CUHK

Presentations
9:30am - 9:45am

Quantification Of Airflow Patterns In A Naturally Ventilated Building Simulated In A Water Table Apparatus

Pooja Mundhe, Rashmin Mohan Damle, Prasad Vaidya, Michael G. Apte

CEPT University, India

Today, most of the people spend 80-90% of the time indoors either in the office or at home. Indoor air is contaminated by human activities and building materials which emit volatile organic compounds. Exposure to these compounds has a short and long-term impact on health. It is therefore important to provide a healthy and productive indoor environment. Acceptable indoor air quality can be maintained by operating a building in natural ventilation, and this can also reduce energy consumption. The water table is an inexpensive, easily accessible apparatus that helps to analyze natural ventilation in buildings due to wind effect and provides instantaneous two-dimensional results of airflow patterns in and around the building. This paper provides and tests a methodology to objectively quantify the images from the water table simulations and calculate results for ventilation metrics like percentage of dead spots, absolute ventilation efficiency, air changes per hour, dose and room mean age of air that quantifies air movement within a physical building model simulated in the apparatus. The quantitative method will help for comparative analysis between design options and make design decisions in terms of opening sizes, orientation, and appropriate positioning of openings optimized for wind-driven naturally ventilated buildings.


9:45am - 10:00am

Indoor Air Quality and Its Effects on Health in Urban Houses of Indonesia

Tetsu Kubota4, Hanief Ariefman Sani1, Usep Surahman2, Sophia Hildebrandt3, Hamidi Ronald5, Beta Paramita6

1Hiroshima University, Japan; 2Univesitas Pendidikan Indonesia, Indonesia; 3University of Leipzig, Germany; 4Hiroshima University, Japan; 5Univesitas Pendidikan Indonesia, Indonesia; 6Univesitas Pendidikan Indonesia, Indonesia

There is a possibility that the sick building syndrome has already spread widely among the newly constructed apartments in major cities of Indonesia. This study investigates the current conditions of indoor air quality, focusing especially on formaldehyde and TVOC, and their effects on health among occupants in the urban houses located in the city of Surabaya. A total of 471 respondents were interviewed and 82 rooms were measured from September 2017 to January 2018. The results indicated that around 50% of the respondents in the apartments showed some degrees of chemical sensitivity risk. More than 60% of the measured formaldehyde levels in the apartments exceeded the WHO standard, 0.08 ppm. The respondents living in rooms with higher mean formaldehyde values tended to have higher multiple chemical sensitivity risk scores.


10:00am - 10:10am

Multilayer Urban Canopy Modelling and Mapping for Traffic Pollutant Dispersion at High Density Urban Areas

Chao Yuan1, Ruiqin Shan1, Yangyang Zhang1, Xianxiang Li2, Tiangang Yim3, Leslie Norford4

1School of Design and Environment, National University of Singapore, Singapore; 2CENSAM, Singapore-MIT Alliance for Research and Technology, Singapore; 3NASA Goddard Space Flight Center, USA; 4Department of Architecture, Massachusetts Institute of Technology, USA

A semi-empirical multilayer urban canopy model is developed to estimate vertical dispersion of traffic emissions in high density urban areas. It is motivated by the heterogeneity of urban morphology in real urban cities and the need of quick urban design and planning. The urban canopy is divided into multiple layers, to include the impact of building height variance on pollutant dispersion. The model is derived by mass conservation within each layer through adopting a box model. The validation study indicates that the new multilayer model performs well to model the vertical pollutant transport, and modelling results can mostly follow the trend of the CFD simulations. A case study was conducted to illustrate how to implement this multilayer urban canopy model in the planning practice.


10:10am - 10:20am

Measuring Infiltration Rates & Leakage in Residential Buildings of Ahmedabad using Blower Door Method

Nikhilesh Singh Bist, Michael G. Apte

CEPT University, India

The need to achieve thermal comfort in residences and strong dependence of air conditioning systems has led to huge energy consumption. In order to reduce the energy consumption of residences and properly size the air conditioners, air leakage needs to be reduced by tighten the building envelope. One such approach to quantify the air leakage is the use of blower door, which uses a powerful calibrated fan to depressurize or pressurize the house at an induced pressure to measure air flow (air leakage) from the house. In this study, 23 residences of Ahmedabad, 12 bungalows and 11 apartments were measured for air leakage. The study is also a first step towards developing methodology to conduct an air tightness test in residential buildings. For comparison, mean normalized leakage (metric for air leakage) of the 23-measured residence was 2.1. Due to old age construction, bungalows have more leakages than apartments. High air flow rates can be observed in buildings with intentional openings, inferior quality windows and cracks on walls. Retrofitting those windows, sealing the intentional openings in an air-conditioned space can lead to huge energy savings for air-conditioned spaces.