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11	Thermomechanical fatigue crack formation in a single crystal Ni-base superalloy Amaro, Robert L. 11 February 2011 (has links) This research establishes a physics-based life determination model for the second generation single crystal superalloy PWA 1484 experiencing out-of-phase thermomechanical fatigue (TMF). The life model was developed as a result of a combination of critical mechanical tests, dominant damage characterization and utilization of well-established literature. The resulting life model improves life prediction over currently employed methods and provides for extrapolation into yet unutilized operating regimes. Particularly, the proposed deformation model accounts for the materials' coupled fatigue-environment-microstructure response to TMF loading. Because the proposed model is be based upon the underlying deformation physics, the model is robust enough to be easily modified for other single crystal superalloys having similar microstructure. Future use of this model for turbine life estimation calculations would be based upon the actual deformation experienced by the turbine blade, thereby enabling turbine maintenance scheduling based upon on a "retirement for a cause" life management scheme rather than the currently employed "safe-life" calculations. This advancement has the ability to greatly reduce maintenance costs to the turbine end-user since turbine blades would be removed from service for practical and justifiable reasons. Additionally this work will enable a rethinking of the warranty period, thereby decreasing warranty related replacements. Finally, this research provides a more thorough understanding of the deformation mechanisms present in loading situations that combine fatigue-environment-microstructure effects. Single crystal Ni-base superalloy Thermomechanical fatigue Bithermal fatigue Life modeling Physics-based modeling Crack initiation Heat resistant alloys Fatigue Heat resistant alloys Cracking Crystals Thermal properties
12	Resilient and Real-time Control for the Optimum Management of Hybrid Energy Storage Systems with Distributed Dynamic Demands Lashway, Christopher R 26 October 2017 (has links) A continuous increase in demands from the utility grid and traction applications have steered public attention toward the integration of energy storage (ES) and hybrid ES (HESS) solutions. Modern technologies are no longer limited to batteries, but can include supercapacitors (SC) and flywheel electromechanical ES well. However, insufficient control and algorithms to monitor these devices can result in a wide range of operational issues. A modern day control platform must have a deep understanding of the source. In this dissertation, specialized modular Energy Storage Management Controllers (ESMC) were developed to interface with a variety of ES devices. The EMSC provides the capability to individually monitor and control a wide range of different ES, enabling the extraction of an ES module within a series array to charge or conduct maintenance, while remaining storage can still function to serve a demand. Enhancements and testing of the ESMC are explored in not only interfacing of multiple ES and HESS, but also as a platform to improve management algorithms. There is an imperative need to provide a bridge between the depth of the electrochemical physics of the battery and the power engineering sector, a feat which was accomplished over the course of this work. First, the ESMC was tested on a lead acid battery array to verify its capabilities. Next, physics-based models of lead acid and lithium ion batteries lead to the improvement of both online battery management and established multiple metrics to assess their lifetime, or state of health. Three unique HESS were then tested and evaluated for different applications and purposes. First, a hybrid battery and SC HESS was designed and tested for shipboard power systems. Next, a lithium ion battery and SC HESS was utilized for an electric vehicle application, with the goal to reduce cycling on the battery. Finally, a lead acid battery and flywheel ES HESS was analyzed for how the inclusion of a battery can provide a dramatic improvement in the power quality versus flywheel ES alone. hybrid energy storage systems energy storage battery physics based modeling battery management systems energy management systems lithium ion batteries lead acid batteries flywheel energy storage systems supercapacitors wide bandgap semiconductors Electrical and Electronics Electromagnetics and Photonics Energy Systems Engineering Physics Power and Energy Transport Phenomena
13	Energy Prediction in Heavy Duty Long Haul Trucks Khuntia, Satvik 22 December 2022 (has links) No description available. Engineering Automotive Engineering Statistics Systems Design Sustainability Transportation Artificial Intelligence Mechanical Engineering "Heavy Duty truck SuperTruck Hoteling hybrid idling Physics based modeling HVAC Vapor compression cycle moving boundary method heat exchanger cabin Machine Learning User activity behavior time allocation matrix transition matrix markov chain driver comfort freight efficiency RNN LSTM powertrain cooling radiator thermostat"

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