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
6ST/2: Science & Technology
Time:
Tuesday, 11/Dec/2018:
1:30pm - 3:30pm

Session Chair: Prof. Adrian Pitts
Location: LT2
Lecture Theatre 2, G/F, Yasumoto International Academic Park, CUHK

Presentations
1:30pm - 1:45pm

Passive Downdraft Cooling Towers Performance Evaluation: Results of data collected from built prototypes

Omar Dhia Sadulah Al-Hassawi1,2

1Washington State University, Pullman, Washington, United States of America; 2Arizona State University, Tempe, Arizona, United States of America

This research aims to advance performance of the single stage passive downdraft evaporative cooling tower (PDECT) and expand its applicability beyond the hot dry conditions where it is typically used by developing and testing a design of a multi-stage passive and hybrid downdraft cooling tower (PHDCT). Experimental evaluation on half-scale prototypes of these towers was conducted in Tempe, Arizona, during Summer, 2017. Cooling systems in both towers were operated simultaneously to evaluate performance under identical conditions. Results indicated that the hybrid tower provides significant advantages over the single stage tower as the former outperformed the latter under all ambient conditions.


1:45pm - 2:00pm

Physical Monitoring of Replacement Infill Panels for Historic Timber-Framed Buildings in the UK: Comparing hygrothermal simulations and dual climate chamber testing

Christopher James Whitman1, Oriel Prizeman1, Julie Gwilliam1, Andrew Shea2, Pete Walker2

1Cardiff University, United Kingdom; 2University of Bath, United Kingdom

With the aim of reducing carbon emissions and increasing hygrothermal comfort, buildings across the UK are undergoing energy retrofits. With historic buildings, it is important that retrofit actions have a limited negative impact on the building’s fabric and cultural significance. Work to date in the UK has focused on the retrofit of historic solid masonry construction, with little research into the retrofit of historic timber-framed buildings. Changes to these buildings must be managed through the use of established conservation principles. However, where infill panels are beyond repair or have previously been substituted with inappropriate materials, there exists the potential to retrofit a material with a higher thermal performance. Nonetheless, it must be ensured that this retrofit does not create interstitial hygrothermal conditions that could threaten the survival of surrounding historic fabric. In this paper the authors present the hygrothermal simulation and physical monitoring of three different potential replacement infill panels. Results from Glaser calculations, WUFI® Pro and WUFI® 2D are compared to measured results of physical test panels mounted between two climate-controlled chambers. Whilst all three prediction methods successfully identified interstitial condensation where it was measured to occur, major discrepancies existed both between simulated and measured results, and between different simulation methods.


2:00pm - 2:15pm

Passive Cooling with Phase Change Materials: Integrative Method for Design of Dendritic Encapsulation Prototype

Iva Resetar, Norbert Palz

Institute for Architecture and Urban Planning, Berlin University of the Arts, Germany

New methods for designing with phase change materials (PCM) could widen the range of applications of passive systems for indoor cooling in architecture. This paper investigates material and formal strategies for generative architectural design that support the thermal performance of PCM. Dendritic geometry of PCM encapsulation with a large surface area per unit volume is proposed for enhancement of the heat transfer between PCM and surroundings. The prototype of the PCM ceiling component is digitally designed, manufactured in glass and tested in an experimental set-up for thermal cycling. Correlations are made between geometric configurations and cooling performance of dendritic and spherical PCM containments. The presented methodology integrates tools and techniques from digital design and energy technology, with an aim to contribute to novel PCM-based concepts for local thermal regulation in architecture.


2:15pm - 2:30pm

Enhancement Of The WUDAPT Portal Tool WUDAPT2ENVI-met: Introducing Site-Specific Local Climate Zones To WUDAPT2ENVI-met

Tim Kropp1, Helge Simon1, Paula Shinzato2, Luciana Schwandner Ferreira2, Carolina Dos Santos Gusson2, Denise Duarte2, Michael Bruse1

1Johannes Gutenberg-University Mainz, Germany; 2University of Sao Paulo, Brasil

The new WUDAPT portal tool 'WUDAPT2ENVI-met' supplies a fast and easy way to generate large urban areas for ENVI-met simulations in a worldwide consistent manner. WUDAPT’s Local Climate Zone Classifications provide spatial information based on satellite imagery, which is translated into large ENVI-met model areas by templates of ENVI-met objects called Standard LCZ tiles. While 17 Local Climate Zone classes seem to be sufficient to describe the inhomogeneity of urban morphologies within one urban area, the inhomogeneity of urban morphologies across different urban areas worldwide might call for more, site-specific morphology classes. Based on this requirement WUDAPT2ENVI-met was enhanced allowing the import of user-generated, site-specific LCZ tiles for the translation. In order to examine whether the Standard LCZ tiles are versatile enough to dissect urban areas worldwide, a classification using the Standard LCZ tiles and specific, user-generated morphologies is compared in a case study of Sao Paulo. Furthermore, the results are compared against a simulation of the same area consisting of the actual building morphology. The comparison showed that the use of site-specific morphologies, materials and plants improved the results, better fitting the results of the actual morphology simulation, which states an important enhancement of the tool.


2:30pm - 2:45pm

Daylighting in Sacred Buildings: Application of Dynamic Brightness Balance and Contrast in divine luminous environment for Energy Saving and Visual Comfort

Annie Sim1, Benson Lau2, Wai Ying Wong3

1Northrop Consulting Engineers, Australia; 2University of Westminster, London, UK; 3CPG Consultants, Singapore

Facing the challenges of global warming, daylighting design optimisation for energy saving and visual comfort has become increasingly important. Across the centuries, architecture precedents have showcased daylighting as one of the key defining elements of spatial quality. While light does not exist in any physical forms, it possesses the superiority to reveal, create and enhance the atmosphere of a physical space, which in-turn impacts the perception and experience of users. How then do we meaningfully make use of this profound natural source to reach our goal in energy savings and visual comfort? This paper investigates different daylighting design strategies in sacred environments, aiming to understand how daylighting strategies using dynamic brightness balance and contrast were applied in two unique sacred structures for enhanced visual perception and energy saving. The research methodology included qualitative field studies by subjective recording of the lit scenes through photographs and hand drawn sketches to assess the visual and biological appreciation of the spaces; and quantitative surveys of brightness contrast in selected visual fields by luminance and illuminance distribution mapping. The research outcomes reveal how visual perception and comfort in sacred environments can be enhanced by appropriate use of daylight, leading to substantial long-term energy saving.


2:45pm - 3:00pm

Effect of Intra- Climate Variation in Thermal Performance of Public Housing in composite climate of India.

Krishan Upadhyay1, Rajasekar Elangovan1, Vaibhav Gupta1, Ashok Kumar2

1Indian Institute of Technology Roorkee, India; 2Central Building Research Institute, India.

This paper deals with the effect of intra-climate diversity of composite climatic zone of India on the thermal performance of the naturally ventilated public housing buildings. This study is an attempt to improve the accuracy of the existing prescriptive benchmarks. The study has two objectives (a) to analyse the thermal severity variation within the composite climate of India and develop a tiered stratification of locations (b) analyse the impact of the thermal severity variation on the performance of representative public housing projects. The scope of study is limited to naturally ventilated residential typology. Data for 162 locations were obtained from Indian Meteorological department (IMD) and statistically analysed in order to classify them based on thermal severities. A review of housing designs of low income group housing being implemented by governmental agencies was reviewed and three representative designs are selected. A short-term thermal performance monitoring is conducted in these residences. The data is used to compare the thermal performance variations as well as to face validate the virtual models developed in Energy Plus software tool. The buildings are simulated for their performance at locations with high, moderate and low thermal severities within composite climate zone. A comparative analysis is carried out with that of NBC prescribed thermal performance guidelines. A set of scaling factors are determined after performing local thermal optimizations at representative locations. The factors are validated with location specific simulations performed for other locations.


3:00pm - 3:15pm

The Impact of External Façade Shading on The Thermal Comfort of Public Rental Housing under Near-extreme Weather Conditions in Hong Kong

Sheng Liu1, Yu Ting Kwok1, Kevin Ka-Lun Lau2,3,4, Edward Yan Yung Ng1,2,3

1School of Architecture,The Chinese University of Hong Kong, Hong Kong S.A.R. (China); 2Institute of Future Cities, The Chinese University of Hong, Hong Kong S.A.R. (China); 3Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong S.A.R. (China); 4CUHK Jockey Club Institute of Ageing, The Chinese University of Hong Kong, Hong Kong S.A.R. (China)

The comfort and health of building occupants are significantly affected by the indoor thermal environment, which can be improved by building envelopes with a good façade design. This study aims to explore the impact of façade shading on the indoor thermal comfort by adding external shading panels on a typical public rental housing building in Hong Kong. Potential improvements on thermal comfort, in terms of indoor operative temperatures (Top), were evaluated for vertical and horizontal shading panels that were tilted at different angles to the façade. Simulation results on DesignBuilder reveal that horizontal shading panels (with a Top reduction up to 0.91˚C) can achieve a better thermal performance than those oriented vertically (with a maximum Top reduction of 0.57˚C). Moreover, shading panels tilted at 90˚ to 45˚ for horizontal panels and at 75˚ to 0˚ for vertical panels were preferred for better thermal performances. This strategy can be readily implemented to procure more sustainable public housing without causing obstructions to the window view of occupants.