DEVELOPMENT OF THERMAL MANAGEMENT TECHNOLOGY ON BRICK WALL FACADES FOR URBAN HEAT ISLAND INTENSITY MITIGATION

• Main Author: Ornam, Kurniati
• Format: Dissertations
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/80030
• Institution: Institut Teknologi Bandung

The escalating phenomenon of increased air temperatures in urban areas, commonly referred to as the urban heat island (UHI), is intricately linked to the thermal properties of building facades within these regions. Heavy building materials, such as brick, exhibit distinct thermal behaviors compared to other materials. In the morning, brick walls absorb heat from solar radiation and tend to retain and store it. During the day, this accumulated heat is released into the surrounding area, contributing to an elevation in air temperature. Subsequently, in the evening, the brick walls reabsorb heat, particularly on the western side, releasing it at night, thus inducing localized heating and an increase in urban heat island intensity (UHII). This research fundamentally aims to identify and develop a model for thermal management technology that holds the potential to be an effective UHII mitigation strategy, specifically targeting residential areas through material interventions in brick facade walls. The study encompasses three stages: 1) direct measurement of UHII in residential areas, aiming to observe UHII patterns in areas with diverse physical environmental characteristics; 2) experimental assessment of thermal management technology effects through material interventions in brick facade walls via direct measurements, aiming to understand heat absorption, storage, and release patterns with and without material interventions in brick facade walls; and 3) evaluating the effectiveness of implementing thermal management technology in residential areas through simulation, focusing on assessing cooling and heating effects for UHII mitigation. The three stages of the research were conducted in a planned residential area characterized by brick construction, with a monitoring period lasting 7 days (7 x 24 hours). In the first stage, Urban Heat Island Intensity (UHII) measurements were taken across various physical environmental features, including roads (wide and narrow) and fields (paved and grass), with East-West and North-South orientations, carried out from October 7 to October 13, 2023. The second stage involved an experimental investigation into the thermal management technology's effects on a three-story building unit. This experimentation occurred from April 18 to April 24, 2021, for the east-facing facade and from July 12 to July 18, 2021, for the west-facing facade, utilizing specimens of brick walls measuring 90 × 90 cm. The measurements, conducted through material intervention on the brick facade employing thermal management technologies (1) absorption (brick wall), (2) conversion (green wall and water-immersed Aluminum Composite Panel [ACP]), (3) reflection (reflective coating), (4) shading (ACP and cement board), and (5) insulation (Expanded Polystyrene [EPS]), included direct assessments (in the first and second stages): air temperature (Ta) in the area using dry and wet thermometers, Ta and surface temperature (Ts) of the walls using thermocouple data loggers, radiation temperature (GT) using globe thermometers, radiation level (SI) using solarmeters, sky conditions (cloud cover) using fish-eye cameras, wind speed (v) using anemometers, and relative humidity (RH) using dry and wet thermometers. Measurements were taken every hour during the morning, afternoon, and evening (06:00-18:00) and every 2 hours during the night until early morning (18:00-06:00). The third stage simulated the effectiveness of implementing thermal management technology on brick facade for UHII mitigation in a residential area using the ENVI-met 4.4.5 software. Simulations were conducted with an east-west orientation of the building facade, considering air temperature (Ta) variables in the residential area for each thermal management technology. Data from the three measurement stages were tabulated in the form of tables, graphs, images, and photographs. Subsequently, the data were analyzed using Analysis of Variance (ANOVA) with JMP Pro 14 software for interpretation and synthesis of the research findings. The research findings demonstrate that thermal management technology, with various material interventions in brick walls, exhibits distinct patterns of heat absorption, storage, and release during different times of the day and night. Interventions in various materials on brick facade walls through diverse thermal management technologies significantly impact UHII mitigation. Brick facade walls absorb heat from solar radiation and emit it back into the surrounding area during both day and night. Absorption technology in brick walls results in a substantial increase in air temperature intensity during the day and night. Insulation technology reduces heat acquisition, leading to lowered air temperatures, particularly effective in conditions of low solar radiation, acting as an effective heat storage mitigator in brick facade walls. ACP, as a shading panel on brick walls with a thin metal layer combined with air gaps, can resist heat flow or radiation penetration from the sun. The shading effect increases surface temperatures on metal shading sheets with excessively hot surfaces, influencing air temperatures during the day. Cement board with shading technology also performs similarly to ACP, albeit with slightly different intensity. Among the various thermal management technologies, conversion and reflective technologies prove to be the most effective in UHII mitigation. Green walls significantly reduce UHII throughout the day, primarily through photosynthesis and evapotranspiration, resulting in an average area temperature reduction of 0.65°C (maximum 0.99°C) during the monitoring period. Reflective coating works effectively in the morning and evening, especially at low sun angles, reducing the average area temperature by 0.53°C (maximum 1.89°C). These findings will prove valuable for architects, urban planners, and policymakers to contribute to UHII mitigation.