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Intensive Surface Water Monitoring Survey for Segment Nos. 0804, 0805, 0806, 0819, & 0822 Trinity River
No full text99 pagesThe purpose of this intensive survey was to provide the Texas Water Quality Board with a valid information source: 1. to determine quantitative cause and effect relationships of water quality; 2. to obtain data for updating water quality management plans, setting effluent limits, and, where appropriate, verifying the classifications of segments; 3. to set priorities for establishing or improving pollution controls; and 4. to determine any additional water quality management actions required
A Data-Driven Approach to Quantifying Flexible Loads in Modern Power Systems
No full textThis thesis investigates the behavior of flexible power demands within the power grid, focusing on two sectors, residential demand response (DR) programs and large flexible loads (LFLs).
Residential DR data sets are challenging to obtain due to costly and intricate nature of conducting DR trials, and user privacy concerns often forbids the data sets to be released publicly to the research community. A generative framework is proposed in this work to create synthetic human-in-the-loop residential demand response data, leveraging external factors such as weather and electricity price. This work allows researchers to generate robust and realistic data sets to simulate the impacts of large-scale residential DR programs in power system management. Conditional Variational Autoencoder (CVAE) is used for the data generation.
As the electric power grid advances towards carbon neutrality, new types of generation and demand will introduce new challenges, one of which is the management of large flexible loads. Within the Texas grid, managed by the Electric Reliability Council of Texas (ERCOT), there currently exists 2.5 gigawatts (GWs) of large flexible load capacity [1]. These types of loads are ideal candidates for DR programs due to its fast ramping capabilities. As the grid evolves to include more intermittent generation sources, flexible demands will undoubtedly play a significant role in system planning.
In this work, we first examine the impact of LFLs on the power grid through three critical factors: reliability, electricity market price, and carbon footprint. We utilize high-granularity large flexible load data to first provide insights to the correlation between LFL and system average price and net load. A high-resolution, open-access tool is created to demonstrate the importance of flexible demand on system reliability, and location impacts on carbon emission. Our study reveals that if the demand is truly flexible, it will have minimal impacts on the power grid even in a renewable-rich system, highlighting the importance of flexible demands in modern power systems.
We further propose an algorithm to detect such flexible demands at the distribution system level. This algorithm is capable of detecting the on/off status of the mining demands and estimating the power consumption magnitude in each household. The results show the proposed algorithm can accurately detect the status of mining machines with above 94% accuracy and calculate its load magnitude with less than 16% error. This tool will provide valuable insights to the system operator, enhancing grid management and enabling DR program participation at the edge-level
Thermal Analysis and 3D Shock Wave Turbulent Boundary Layer Interactions in a Canonical Hypersonic Inlet
Get PDFHypersonics is an exciting, yet extremely complex field of study in which numerous challenges still exist. One of these challenges is the prediction of heating to the vehicle���s surface, which ultimately impacts the vehicle���s design, performance capabilities, and safety. Shock boundary layer interactions have been studied for decades and are known to be a major factor in surface heating, but this phenomenon, especially within the context of 3D hypersonic turbulent flow, is not well understood. The overarching objective of this research endeavor is to better understand turbulent shock boundary layer interactions and other complex flow features including shock-shock interactions and vortex boundary layer interactions in a 3D hypersonic flowfield. This work encompasses the design, fabrication, verification, and validation of a versatile canonical inlet test article and the experimental data obtained on the aforementioned complex flow features generated from this geometry. Experimental data was collected in the National Aerothermochemistry and Hypersonic Laboratory���s Actively Controlled Expansion tunnel at Texas A&M University at M =��� 5.7 and Re/m =��� 6.1x10^6. A combination of conventional methods and advanced non-intrusive laser diagnostics were used including oil flow, Z-Type Schlieren, NO PLIF, and IR thermography. These studies provided insight into the velocity and thermal boundary layer upstream and downstream of the compression corners, as well as surface heat transfer along the inlet test article and the effects of shock boundary layer interactions on surface heat transfer. These data were compared to FLEET velocimetry results and numerical simulations for further insight and analyses. Overall, the data obtained from these experiments agreed well with the simulations in regions unaffected by the shock boundary layer interactions, shock-shock interactions, and vortex boundary layer interactions. More discrepancies between the data and simulations were observed in regions where these flow features were present. Another key finding was that the shock boundary layer interaction had a significant impact on surface heat flux, leading to increases on the order of 50% or more in some instances. This work contributes to a growing knowledge base of complex hypersonic flow, and ultimately, could assist with improved hypersonic vehicle design and heating predictions
