Numerical tests of the weak pressure gradient approximation
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This project focused on developing advanced methods for thermal performance monitoring of a coal-fueled power plant. The specific goal was to develop and demonstrate a new thermal performance monitoring approach using a hybrid model that integrates a physics-based heat balance model with a machine learning-based pattern recognition model. The hybrid model enables increased accuracy and scope of the thermal analysis and an improved ability to monitor and detect changes in plant operation. This new approach takes full advantage of the individual model capabilities and creates an important new set of capabilities not previously possible using the two types of models separately. Using the heat balance model, a rich set of derived parameters (virtual sensors) are calculated from the measured plant operating data at each time point. The combined measured and derived data values are used by machine learning algorithms to create pattern recognition models over the range of normal unit operation. To create the monitoring models, historical data from normal operation of the plant is first processed by the heat balance model to compute the derived parameter data. The result is a greatly expanded set of normal operating data that can be used as input to create the pattern recognition model. Once the models are calibrated for normal operation, the hybrid model is suitable for use in continuous online monitoring. During online monitoring, new plant operating data is processed first by the heat balance model and then by the pattern recognition model. Results from the pattern recognition model quantify the deviation of each measured or derived parameter from its expected value in normal operation. The hybrid models can detect abnormal changes in plant operating data with very high accuracy and sensitivity. When abnormal behavior is detected, alerts are generated automatically for evaluation by the plant monitoring staff. The new hybrid solution product was developed and verified in the performance of the project. The hybrid solution was tested first in a simulation environment that mimicked the plant data systems and infrastructure used by U.S. power generating plants and utilities. The hybrid solution was then deployed for real-time, online monitoring of an operating coal-fueled power plant at a field test site. Field testing demonstrated that all hybrid solution development objectives were accomplished. The project work was based on combining the capabilities of two existing software products to create the new hybrid solution product. One of these was the existing MapEx® heat balance product and the other was the existing SureSense® advanced pattern recognition product. Each of these separate products was assessed to be at a Technology Readiness Level (TRL) of 9 at the start of the effort. The hybrid solution product was assessed to be at a TRL of 2 at the start of the project based on early feasibility work by the project team. At completion of the field testing performed in the project, the hybrid solution product was assessed to be at a TRL of 7. The project team expects that the hybrid solution product will be deployed commercially and will achieve a TRL of 9 within one year after completion of the project.
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Two methods for solving sixth-order linear system constituting the motion equations for midcourse phase of a ballistic interplanetary flight
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Peripheral wall conduction effect on laminar forced convection in rectangular channels
Peripheral wall conduction effect on laminar forced convection in rectangular channels
Solutions to hydrogen-oxygen reaction ignition kinetics
Particle trajectories in model current sheets with magnetic field parallel and perpendicular to neutral sheet
Differential equations for governing motion of vehicle in uniform gravitational fields
Infinite power series to solve perturbation equation for ground state of helium atom
Optimal two impulse transfer through 180 degree range angle between Keplerian noncoplanar orbits, minimizing impulse by transfer plane optimal orientation
Mathematical model for voltage step-down DC to DC converter with hysteretic bistable trigger circuit regulating output voltage
Instantaneous frozen layer thickness and temperature profile in solidified layer obtained by iteration technique
Partial differential equation solution for wind-driven circulation in shallow seas or lakes
Optimal two impulse transfer through 180 degree range angle between Keplerian noncoplanar orbits, minimizing impulse by transfer plane optimal orientation
Milne-Eddington atmosphere, using Unno transfer equations for Stokes parameters