Matching Items (7)
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- All Subjects: Architecture
- Creators: Reddy, T Agami
Description
The ability to design high performance buildings has acquired great importance in recent years due to numerous federal, societal and environmental initiatives. However, this endeavor is much more demanding in terms of designer expertise and time. It requires a whole new level of synergy between automated performance prediction with the human capabilities to perceive, evaluate and ultimately select a suitable solution. While performance prediction can be highly automated through the use of computers, performance evaluation cannot, unless it is with respect to a single criterion. The need to address multi-criteria requirements makes it more valuable for a designer to know the "latitude" or "degrees of freedom" he has in changing certain design variables while achieving preset criteria such as energy performance, life cycle cost, environmental impacts etc. This requirement can be met by a decision support framework based on near-optimal "satisficing" as opposed to purely optimal decision making techniques. Currently, such a comprehensive design framework is lacking, which is the basis for undertaking this research. The primary objective of this research is to facilitate a complementary relationship between designers and computers for Multi-Criterion Decision Making (MCDM) during high performance building design. It is based on the application of Monte Carlo approaches to create a database of solutions using deterministic whole building energy simulations, along with data mining methods to rank variable importance and reduce the multi-dimensionality of the problem. A novel interactive visualization approach is then proposed which uses regression based models to create dynamic interplays of how varying these important variables affect the multiple criteria, while providing a visual range or band of variation of the different design parameters. The MCDM process has been incorporated into an alternative methodology for high performance building design referred to as Visual Analytics based Decision Support Methodology [VADSM]. VADSM is envisioned to be most useful during the conceptual and early design performance modeling stages by providing a set of potential solutions that can be analyzed further for final design selection. The proposed methodology can be used for new building design synthesis as well as evaluation of retrofits and operational deficiencies in existing buildings.
ContributorsDutta, Ranojoy (Author) / Reddy, T Agami (Thesis advisor) / Runger, George C. (Committee member) / Addison, Marlin S. (Committee member) / Arizona State University (Publisher)
Created2013
Description
ABSTRACT Leadership in Energy and Environmental Design (LEED) is a non-governmental organization of U.S. Green Building Council (USGBC) which promotes a sustainable built environment with its rating systems. One of the building segments which it considers is healthcare, where it is a challenge to identify the most cost-effective variety of complex equipments, to meet the demand for 24/7 health care and diagnosis, and implement various energy efficient strategies in inpatient hospitals. According to their “End Use Monitoring” study, Hospital Energy Alliances (HEA), an initiative of U.S. Department of Energy (DOE), reducing plug load reduces hospital energy consumption. The aim of this thesis is to investigate the extent to which realistic changes to the building envelope, together with HVAC and operation schedules would allow LEED credits to be earned in the DOE–hospital prototype. The scope of this research is to specifically investigate the inpatient block where patient stays longer. However, to obtain LEED credits the percentage cost saving should be considered along with the end use monitoring. Several steps have been taken to identify the optimal set of the end use results by adopting the Whole Building Energy Simulation option of the LEED Energy & Atmosphere (EA) pre– requisite 2: Minimum Energy Performance. The initial step includes evaluating certain LEED criteria consistent with ASHRAE Standard 90.1–2007 with the constraint that hospital prototype is to be upgraded from Standard 2004 to Standard 2007. The simulation method stipulates energy conservation measures as well as utility costing to enhance the LEED credits. A series of simulations with different values of Light Power Density, Sizing Factors, Chiller Coefficient of Performance, Boiler Efficiency, Plug Loads and utility cost were run for a variety of end uses with the extreme climatic condition of Phoenix. These assessments are then compared and used as a framework for a proposed interactive design decision approach. As a result, a total of 19.4% energy savings and 20% utility cost savings were achieved by the building simulation tool, which refer to 5 and 7 LEED credits respectively. The study develops a proper framework for future evaluations intended to achieve more LEED points.
ContributorsHaque, Sadia Khandaker (Author) / Reddy, T A (Thesis advisor) / Bryan, Harvey J. (Committee member) / Addison, Marlin S. (Committee member) / Arizona State University (Publisher)
Created2012
Description
In geographical locations with hot-arid climates, sun control in buildings is one primary problem to solve for the building envelope design. Today's technological advances in building science bring with them the opportunity to design dynamic façade systems for sun radiation control and daylighting. Although dynamic systems can become an attractive visual element, they can be costly and challenging to maintain for building owners. Alternatively, fixed solar-shading systems can be designed to create dynamism in the façade of the building, while providing similar functionalities for sun control. The work presented in this project focuses on the use of a visual scripting editor for modeling software, Grasshopper, to develop a Solar Control Visual Script that evaluates building envelope surfaces with planar and non-uniform rational basis-spline (NURBS) forms and provides projections for fixed sun control systems. The design platform of Grasshopper allows individuals with no experience or prior computer coding education to build up programming-like capabilities; this feature permits users to discover new design possibilities within flexible frames that can contribute to the overall design being pursued, while also having an environmental response. The Solar Control Visual Script provides minimum sizing geometries that achieve shading in openings at a particular date and time of the year. The model for this method of analysis makes use of three components to derive the appropriate values for the projections of shading geometries: typical meteorological year (TMY) data, irradiation isotropic equations and shading profile angles equations for vertical and tilted surfaces. Providing an automatic visual of generated geometries uncovers the opportunity to test several model forms and reiterates the analysis when modifying control parameters. By employing building science as a set of environmental parameters, the design outcome bears a dynamic form that responds to natural force conditions. The optimized results promote an efficient environmental design solution for sun control as an integral alternative into the building envelope.
ContributorsGrijalva, Karla (Author) / Bryan, Harvey J. (Thesis advisor) / Griffiths, Jason (Committee member) / Kroelinger, Michael D. (Committee member) / Arizona State University (Publisher)
Created2012
Description
Passive cooling techniques, specifically passive downdraft cooling (PDC), have proven to be a solution that can address issues associated with air conditioning (AC). Globally, over 100 buildings have integrated PDC in its different forms, most of which use direct evaporative cooling. Even though all surveyed buildings were energy efficient and cost-effective and most surveyed buildings were thermally comfortable, application of PDC remains limited. This study 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 designing and testing 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 the hot dry and hot humid days of Summer, 2017. Ambient air dry-bulb temperatures ranged between 73.0°F with 82.9 percent coincident relative humidity, and 123.4°F with 7.8 percent coincident relative humidity. Cooling systems in both towers were operated simultaneously to evaluate performance under identical conditions.
Results indicated that the hybrid tower outperformed the single stage tower under all ambient conditions and that towers site water consumption was at least 2 times lower than source water required by electric powered AC. Under hot dry conditions, the single stage tower produced average temperature drops of 35°F (5°F higher than what was reported in the literature), average air velocities of 200 fpm, and average cooling capacities of 4 tons. Furthermore, the hybrid tower produced average temperature drops of 45°F (50°F in certain operation modes), average air velocities of 160 fpm, and average cooling capacities exceeding 4 tons. Under hot humid conditions, temperature drops from the single stage tower were limited to the ambient air wet-bulb temperatures whereas drops continued beyond the wet-bulb in the hybrid tower, resulting in 60 percent decline in the former’s cooling capacity while maintaining the capacity of the latter. The outcomes from this study will act as an incentive for designers to consider incorporating PDC into their designs as a viable replacement/supplement to AC; thus, reducing the impact of the built environment on the natural environment.
Results indicated that the hybrid tower outperformed the single stage tower under all ambient conditions and that towers site water consumption was at least 2 times lower than source water required by electric powered AC. Under hot dry conditions, the single stage tower produced average temperature drops of 35°F (5°F higher than what was reported in the literature), average air velocities of 200 fpm, and average cooling capacities of 4 tons. Furthermore, the hybrid tower produced average temperature drops of 45°F (50°F in certain operation modes), average air velocities of 160 fpm, and average cooling capacities exceeding 4 tons. Under hot humid conditions, temperature drops from the single stage tower were limited to the ambient air wet-bulb temperatures whereas drops continued beyond the wet-bulb in the hybrid tower, resulting in 60 percent decline in the former’s cooling capacity while maintaining the capacity of the latter. The outcomes from this study will act as an incentive for designers to consider incorporating PDC into their designs as a viable replacement/supplement to AC; thus, reducing the impact of the built environment on the natural environment.
ContributorsAl-Hassawi, Omar Dhia Sadulah (Author) / Bryan, Harvey (Thesis advisor) / Reddy, T Agami (Committee member) / Chalfoun, Nader (Committee member) / Arizona State University (Publisher)
Created2017
Description
Schools all around the country are improving the performance of their buildings by adopting high performance design principles. Higher levels of energy efficiency can pave the way for K-12 Schools to achieve net zero energy (NZE) conditions, a state where the energy generated by on-site renewable sources are sufficient to meet the cumulative annual energy demands of the facility. A key capability for the proliferation of Net Zero Energy Buildings (NZEB) is the need for a design methodology that identifies the optimum mix of energy efficient design features to be incorporated into the building. The design methodology should take into account the interaction effects of various energy efficiency measures as well as their associated costs so that life cycle cost can be minimized for the entire life span of the building.
This research aims at developing such a methodology for generating cost effective net zero energy solutions for school buildings. The Department of Energy (DOE) prototype primary school, meant to serve as the starting baseline, was modeled in the building energy simulation software eQUEST and made compliant with the requirement of ASHRAE 90.1-2007. Commonly used efficiency measures, for which credible initial cost and maintenance data were available, were selected as the parametric design set. An initial sensitivity analysis was conducted by using the Morris Method to rank the efficiency measures in terms of their importance and interaction strengths. A sequential search technique was adopted to search the solution space and identify combinations that lie near the Pareto-optimal front; this allowed various minimum cost design solutions to be identified corresponding to different energy savings levels.
Based on the results of this study, it was found that the cost optimal combination of measures over the 30 year analysis span resulted in an annual energy cost reduction of 47%, while net zero site energy conditions were achieved by the addition of a 435 kW photovoltaic generation system that covered 73% of the roof area. The simple payback period for the additional technology required to achieve NZE conditions was calculated to be 26.3 years and carried a 37.4% premium over the initial building construction cost. The study identifies future work in how to automate this computationally conservative search technique so that it can provide practical feedback to the building designer during all stages of the design process.
This research aims at developing such a methodology for generating cost effective net zero energy solutions for school buildings. The Department of Energy (DOE) prototype primary school, meant to serve as the starting baseline, was modeled in the building energy simulation software eQUEST and made compliant with the requirement of ASHRAE 90.1-2007. Commonly used efficiency measures, for which credible initial cost and maintenance data were available, were selected as the parametric design set. An initial sensitivity analysis was conducted by using the Morris Method to rank the efficiency measures in terms of their importance and interaction strengths. A sequential search technique was adopted to search the solution space and identify combinations that lie near the Pareto-optimal front; this allowed various minimum cost design solutions to be identified corresponding to different energy savings levels.
Based on the results of this study, it was found that the cost optimal combination of measures over the 30 year analysis span resulted in an annual energy cost reduction of 47%, while net zero site energy conditions were achieved by the addition of a 435 kW photovoltaic generation system that covered 73% of the roof area. The simple payback period for the additional technology required to achieve NZE conditions was calculated to be 26.3 years and carried a 37.4% premium over the initial building construction cost. The study identifies future work in how to automate this computationally conservative search technique so that it can provide practical feedback to the building designer during all stages of the design process.
ContributorsIslam, Mohammad Moshfiqul (Author) / Reddy, T. Agami (Thesis advisor) / Bryan, Harvey J. (Committee member) / Addison, Marlin (Committee member) / Arizona State University (Publisher)
Created2016
Description
The rapid rate of urbanization coupled with continued population growth and anthropogenic activities has resulted in a myriad of urban climate related impacts across different cities around the world. Hot-arid cities are more vulnerable to induced urban heat effects due to the intense solar radiation during most of the year, leading to increased ambient air temperature and outdoor/indoor discomfort in Phoenix, Arizona. With the fast growth of the capital city of Arizona, the automobile-dependent planning of the city contributed negatively to the outdoor thermal comfort and to the people's daily social lives. One of the biggest challenges for hot-arid cities is to mitigate against the induced urban heat increase and improve the outdoor thermal. The objective of this study is to propose a pragmatic and useful framework that would improve the outdoor thermal comfort, by being able to evaluate and select minimally invasive urban heat mitigation strategies that could be applied to the existing urban settings in the hot-arid area of Phoenix. The study started with an evaluation of existing microclimate conditions by means of multiple field observations cross a North-South oriented urban block of buildings within Arizona State University’s Downtown campus in Phoenix. The collected data was evaluated and analyzed for a better understanding of the different local climates within the study area, then used to evaluate and partially validate a computational fluid dynamics model, ENVI-Met. Furthermore, three mitigation strategies were analyzed to the Urban Canopy Layer (UCL) level, an increase in the fraction of permeable materials in the ground surface, adding different configurations of high/low Leaf Area Density (LAD) trees, and replacing the trees configurations with fabric shading. All the strategies were compared and analyzed to determine the most impactful and effective mitigation strategies. The evaluated strategies have shown a substantial cooling effect from the High LAD trees scenarios. Also, the fabric shading strategies have shown a higher cooling effect than the Low LAD trees. Integrating the trees scenarios with the fabric shading had close cooling effect results in the High LAD trees scenarios. Finally, how to integrate these successful strategies into practical situations was addressed.
ContributorsAldakheelallah, Abdullah (Author) / Reddy, T Agami (Thesis advisor) / Middel, Ariane (Committee member) / Coseo, Paul (Committee member) / Arizona State University (Publisher)
Created2020
Description
Building-integrated carbon-capture (BICC) is an envisioned mechanism capable of absorbing carbon dioxide (CO2) from the air to be stored and then converted into useful carbon-based materials without negatively impacting the environment. This dissertation builds on the authors' previous work, in which building façades were treated as artificial leaves capable of providing shade to lower solar heat gain, while simultaneously capturing CO2 through the air filters attached to the building façades by attempting a different approach capable of capturing CO2 within buildings. This dissertation presents the author’s work on BICC, where buildings are envisioned as CO2 reservoirs or vacuums, into which mechanical systems introduce fresh air, and through human activities, the air within the building becomes enriched with CO2 before being pushed out back to the outer environment. The design of a carbon-capture mechanism will take advantage of the ventilation side of existing HVAC systems, through which BICC captures CO2 from the exhaust-enriched CO2 air. BICC will utilize existing opportunities and components within buildings represented in the high CO2 concentration in buildings, ventilation guidelines, mechanical equipment represented in air handling unit and air duct network, in addition to natural gas grid connectivity. BICC will capture CO2 through buildings' mechanical system, and the captured CO2 would then be converted into renewable methane to be injected into the existing natural gas pipeline network. This dissertation will investigate the potential of BICC to offset carbon emissions from multiple commercial building types and will present a utilization strategy for the captured carbon.
ContributorsBen Salamah, Fahad (Author) / Bryan, Harvey (Thesis advisor) / Lackner, Klaus (Committee member) / Reddy, T Agami (Committee member) / Arizona State University (Publisher)
Created2021