Engineering Commons^™

Building Envelope Wind Pressure Manipulation For Application In Streamlined High-Rise Buildings, Sivaramprasad Sivakumar

Mechanical and Aerospace Engineering - Dissertations

This research investigates methods of manipulating building envelope wind pressure distribution for application in the natural ventilation of high-rise buildings. CFD simulations are employed to predict the wind pressure distribution around the building envelope. First, a 2-D CFD study is conducted to explore various techniques of manipulating the building envelope wind pressure distribution. This study indicates that the use of externally mounted flow-resistance devices is an effective method of manipulating the wind pressure distribution. It is demonstrated that this technique is well suited for application to buildings of streamlined cross-section (e.g. elliptical planform). Next, a 3-D CFD study is conducted …

Enriching Step-Based Product Information Models To Support Product Life-Cycle Activities, Mehmet Ilteris Sarigecili

Mechanical and Aerospace Engineering - Dissertations

The representation and management of product information in its life-cycle requires standardized data exchange protocols. Standard for Exchange of Product Model Data (STEP) is such a standard that has been used widely by the industries. Even though STEP-based product models are well defined and syntactically correct, populating product data according to these models is not easy because they are too big and disorganized. Data exchange specifications (DEXs) and templates provide re-organized information models required in data exchange of specific activities for various businesses. DEXs show us it would be possible to organize STEP-based product models in order to support different …

Champs-Multizone And Virtual Building For Integrated Building Systems Design And Performance Evaluation, Wei Feng

Mechanical and Aerospace Engineering - Dissertations

The ultimate goal of this research was to develop an integrated framework that facilitates performance-based multi-stage design of buildings and comparison between the performance predicted at the design stage and that monitored at operation stage. Such an integrated framework would not only enable design optimization, but also enable confirmation of design intent or diagnosis of performance deficiency, and thus provide feedbacks for future building design. This dissertation study represents the first step toward this ultimate goal, and had the following specific objectives:: 1) developing a combined heat, air, moisture and pollutant transport model for whole building performance simulation; 2) developing …

Development Of A Novel Statistical Method And Procedure For Material Characterization And A Probabilistic Approach To Assessing The Hygrothermal Performance Of Building Enclosure Assemblies, Jianhua Zhao

Mechanical and Aerospace Engineering - Dissertations

In this research, a systematic approach was introduced to establish a high quality and comprehensive material database. The method was applied to a great number of materials in different material categories. The database provides a solid base for hygrothermal simulation and further research.

A method was developed to derive the generic material from the material cluster comprising specific materials with similar characteristics. A novel approach was developed by using the generic material to extrapolate less incomplete material data set to full data set that is suitable for the hygrothermal simulation. The approach extends the material database, and hence enhances the …

Shape Memory Assisted Self Healing (Smash) Polymeric And Composite Systems, Erika D. Rodriguez

Mechanical and Aerospace Engineering - Dissertations

My research aims to develop a novel approach that uses the shape memory (SM) effect to aid self healing (SH) polymeric systems that are able to simultaneously close and re-bond cracks with a single thermal stimulus. This new concept is termed shape memory assisted self healing (SMASH). Additionally, a new type of shape memory termed reversible plasticity shape memory (RPSM) was also developed where both the elastic and plastic deformation found after deformation completely recover upon a thermal stimulation. I aim to utilize a broad range of polymeric and composite systems that include a single phase semi-crystalline system, a single …

Functional And Behavioral Product Information Representation And Consistency Validation For Collaboration In Product Lifecycle Activities, Mehmet Murat Baysal

Mechanical and Aerospace Engineering - Dissertations

Information models that represent the function, assembly and behavior of artifacts are critical in the conceptual development of a product and its evaluation. Much research has been conducted in this area; however, existing models do not relate function, behavior and structure in a comprehensive and consistent way. In this work, NIST's Core Product Model (CPM) and the Open Assembly Model (OAM) are extended to integrate product information including function and behavior, with an emphasis on assembly, throughout all phases of product development. For function and flow classification, the NIST functional taxonomy is used to maintain consistency with the literature.

The …

Effects Of Surface Roughness On The Indoor Particle Deposition Rate Constant, Shaojie Wang

Mechanical and Aerospace Engineering - Dissertations

The purpose of this work was to quantify the deposition rate constants of size-classified particles on typical indoor surface materials as affected by the degree of surface roughness. The experiments were conducted in a small-scale acrylic chamber. The particle size range was from 0.723 to 5.048 £gm with 28 size bins. The air change rates were 6, 11 and 13 h-1. The TSI large particle aerosol generator 8108 was used to generate potassium chloride as test particles, and the TSI aerodynamic particle sizer (APS3321) was used to measure the particle number concentrations. Particle deposition rate constants were determined by regression …

Modeling And Managing Engineering Changes In A Complex Product Development Process, Weilin Li

Mechanical and Aerospace Engineering - Dissertations

Today's hyper-competitive worldwide market, turbulent environment, demanding customers, and diverse technological advancements force any corporations who develop new products to look into all the possible areas of improvement in the entire product lifecycle management process. One of the areas that both scholars and practitioners have overlooked in the past is Engineering Change Management (ECM).

The vision behind this dissertation is to ultimately bridge this gap by identifying main characteristics of a New Product Development (NPD) process that are potentially associated with the occurrence and magnitude of iterations and Engineering Changes (ECs), developing means to quantify these characteristics as well as …

Thermally Aware, Energy-Based Techniques For Improving Data Center Energy Efficiency, Dustin W. Demetriou

Mechanical and Aerospace Engineering - Dissertations

This work investigates the practical implementation of so-called thermally aware, energy optimized load placement in air-cooled, raised floor data centers to reduce the overall energy consumption, while maintaining the reliability of the IT equipment. The work takes a systematic approach to modeling the data center's airflow, thermodynamic and heat transfer characteristics - beginning with simplified, physics-inspired models and eventually developing a high-fidelity, experimentally validated thermo-hydraulic model of the data center's cooling and power infrastructure. The simplified analysis was able to highlight the importance of considering the trade-off between low air supply temperature and increased airflow rate, as well as the …

Study Of Vocs Transport And Storage In Porous Media And Assemblies, Jing Xu

Mechanical and Aerospace Engineering - Dissertations

Indoor VOCs concentrations are influenced greatly by the transport and storage of VOCs in building and furnishing materials, majority of which belong to porous media. The transport and storage ability of a porous media for a given VOC can be characterized by its diffusion coefficient and partition coefficient, respectively, and such data are currently lacking. Besides, environmental conditions are another important factor that affects the VOCs emission. The main purposes of this dissertation are: (1) validate the similarity hypothesis between the transport of water vapor and VOCs in porous materials, and help build a database of VOC transport and storage …

Dynamic Botanical Filtration System For Indoor Air Purification, Zhiqiang Wang

Mechanical and Aerospace Engineering - Dissertations

A dynamic botanical air filtration (DBAF) system was developed, tested and modeled for indoor air purification. The DBAF system consisted of an activated-carbon/hydroculture-based root bed for potted-plant, a fan for driving air through the root bed for purification, and an irrigation system for maintaining proper moisture content in the root bed. Results from test conducted in a full-scale open office space indicated that the filtration system had ability to supply clean air equivalent to 80% of required outdoor air supply for the space. The DBAF was effective for removing both formaldehyde and toluene at 5 to 32% volumetric water content …

A Detailed And Systematic Investigation Of Personal Ventilation Systems, Jackie Russo

Mechanical and Aerospace Engineering - Dissertations

This research investigates the use of personal ventilation (PV) in a typical office space as a means of contaminant removal from ones breathing zone (BZ). For this work, a validated computational model was developed and used for PV assessment under different scenarios. Experimental data of Khalifa et al. (2009), Ito (2007) and Rim et al. (2009) were used to validate a computational model that is capable of simulating indoor chemical reactions with excellent agreement compared with the experiments. Through the validation process, various computational parameters were determined to be significant for producing accurate results. Grid resolution, geometry, far field BCs, …