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Full-Text Articles in Mechanical Engineering
Validation Of A Fault-Modeling Equipped Vapor Compression System Model Using A Fault Detection And Diagnostics Evaluation Tool, David P. Yuill, Howard Cheung, James E. Braun
Validation Of A Fault-Modeling Equipped Vapor Compression System Model Using A Fault Detection And Diagnostics Evaluation Tool, David P. Yuill, Howard Cheung, James E. Braun
David Yuill
A methodology for evaluating the performance of fault detection and diagnostics (FDD) tools for unitary air- conditioners has been developed (Yuill and Braun 2013). The methodology uses laboratory measurements of systems with and without faults to test FDD tools’ effectiveness. A gray box modeling method capable of modeling systems with faults was developed by Cheung and Braun (2013a and 2013b) to provide input data, as an alternative to using laboratory data that had been collected. The simulation method was validated by direct comparison with experimental data, but a comparison of FDD evaluation results provides a more direct and useful validation …
Development Of A Model Predictive Controller For Tankless Water Heaters, Gregor P. Henze, David P. Yuill, Andrew H. Coward
Development Of A Model Predictive Controller For Tankless Water Heaters, Gregor P. Henze, David P. Yuill, Andrew H. Coward
David Yuill
This paper describes the development of a novel approach to temperature control of tankless water heaters (TWHs). Conventional methods of controlling TWHs typically allow a high degree of error in the outlet water temperature when subjected to disturbances in flow rate or inlet water temperature. Poor control affects comfort, safety, and energy consumption associ- ated with TWHs. The novel control approach presented here uses model predictive control (MPC) to minimize the outlet temperature error. A dynamic heat transfer model of an electric TWH is developed and validated and used within a MPC-based controller. The controller is interfaced to a physical …
Modeling Of The Effects Of Athermal Flow Strength And Activation Energy For Dislocation Glide On The Nanoindentation Creep Of Nickel Thin Film At Room Temperature
A.S. Md Abdul Haseeb
Nanoindentation creep behaviour of nickel at room temperature has been modeled based on the obstacle-controlled dislocation glide mechanism. Using the model, the effects of two important materials parameters viz. the activation free energy required by dislocation to overcome an obstacle without any aid from external stress, ΔF and the athermal flow strength, τ0, which is the flow strength of solids at 0 K are systematically studied. It has been found that ΔF plays a dominant role in room temperature creep properties of nickel. The role of ΔF is particularly dominant in determining the time dependent deformation. On the other hand, …
Modeling Of The Effects Of Athermal Flow Strength And Activation Energy For Dislocation Glide On The Nanoindentation Creep Of Nickel Thin Film At Room Temperature
A.S. Md Abdul Haseeb
Nanoindentation creep behaviour of nickel at room temperature has been modeled based on the obstacle-controlled dislocation glide mechanism. Using the model, the effects of two important materials parameters viz. the activation free energy required by dislocation to overcome an obstacle without any aid from external stress, ΔF and the athermal flow strength, τ0, which is the flow strength of solids at 0 K are systematically studied. It has been found that ΔF plays a dominant role in room temperature creep properties of nickel. The role of ΔF is particularly dominant in determining the time dependent deformation. On the other hand, …