Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 25 for “"Two-Zone"”.
-
One-Dimensional Performance Modeling of Centrifugal Flow Vaned Diffusers
The Two Element in Series (TEIS) and Two Zone models stand out as powerful tools that enable deeper understanding of compressor stage designs after they have been tested. The insights gained from these investigations have aided in improving new stage designs. Up to now, it has only been possible to …
-
One-Dimensional Radial Flow Turbomachinery Performance Modeling
The Two-Element In Series (TEIS) and Two-Zone models have been used successfully for over twenty years to model test data for radial flow compressors and pumps. The models can also be used to predict the performance of new machines provided that the model inputs can be accurately specified. …
-
Stochastic analysis of dense nonaqueous phase liquid dissolution in naturally heterogeneous subsurface systems
… DNAPL saturation distribution in a source zone is derived, based on the previous research to describe the field-scale nonuniform residual DNAPL distribution. A local-scale dissolution model is generalized from the laboratory experimental results. Effective transport and dissolution …
-
Gas-solid transport and reaction via intervened evaporating sprays
… in FCC process models have progressed along two lines. One aims to develop composition-based kinetic models derived from molecular characterization of petroleum fractions while overlooking the hydrodynamic effect on local catalyst to oil ratio (CTO). The other aims to develop computational …
-
In Situ X-Ray Investigations of Staging and Sequencing In Potassium-Graphite Intercalation Compounds
… have been performed in situ by means of a two-zone, high-temperature, x-ray furnace. The transition from stage 1 to stage 2 is found to be a two-phase process which does not require intermediate steps. For stage n, n (GREATERTHEQ) 2, stage mixing is shown to occur in thermodynamic …
-
Effect of STATCOM Location on Distance Protection Relay Operation
… Based on the dynamic behaviour of STATCOM in a two-machine system, where a distance protection scheme is applied, performance of the two zone distance protection scheme has been evaluated in EMTDC/PSCAD simulation environment for various contingent conditions. This includes different STATCOM …
-
A computational and experimental study of spark ignition engine combustion
… code which could operate in either a three-zone entrainment and bum up, or a two-zone direct combustion, configuration. The pent-roof engine was skip-fired to ensure residual gases were purged and care was taken to ensure that the thermodynamic state and chemical composition of the intake …
-
An investigation, comparison, and development of individual tree competition models
… individual tree competition model based on the zone of influence principle was developed and tested on data from two young loblolly pine plantation stands. Analyses indicated that, depending on stand, diameter distribution and spatial arrangement, the model acted either as a competition …
-
Modeling and characterizing bi-directional airflow in natural ventilation
… using computational fluid dynamics (CFD). Two important scenarios are simulated and analyzed: 1. Two-zone model with pure buoyancy forces, 2. Multi-zone model with combined wind and buoyancy forces. In the 1st model, a new concept of "local discharge coefficient" is proposed for its …
-
In situ x-ray investigations of staging and sequencing potassium-graphite intercalation compounds
… have been performed in situ by means of a two-zone, high-temperature, x-ray furnace. The transition from stage 1 to stage 2 is found to be a two-phase process which does not require intermediate steps. For stage n, n > 2, stage mixing is shown to occur in thermodynamic equilibrium. The …
-
Modelling and simulation of combustion of dilute syngas fuels in a CFR engine
… model of the CFR engine in GT-POWER. Using two-zone modelling and detailed chemical kinetics, the model is also able to determine the performance of the engine along with any associated knocking tendency of the fuel and its corresponding operating conditions. Validation and tuning of the …
-
Clustering and Hybrid Routing in Mobile Ad Hoc Networks
… clustering and hybrid routing in Mobile Ad Hoc Networks (MANET). Specifically, we study two different network-layer virtual infrastructures proposed for MANET: the explicit <em>cluster </em>infrastructure and the implicit <em>zone</em> infrastructure. In the first part of the dissertation, we …
-
Dynamic performance of control loops and their interactions in a VAV HVAC system
… this objective, experiments were conducted in a two-zone VAV test facility. The facility consists of six control loops (cooling valve, fan speed, two dampers, two electric heaters) activated by DDC PI controllers. Experiments were conducted in this facility and the results were processed, and …
-
Modelling of Ignition and Fire in Vented Enclosures
… moment of ignition incorporating the traditional two-zone approach. During early fIre development the density and temperature of the lower zone are reasonably assumed to be close to their initial value. Flashover itself is assumed to occur early in the fIre development, within the fuel controlled …
-
Spatially Resolved Species and Temperature Profiles in the Oxidative Dehydrogenation of Ethane on Mono and Bimetallic Catalysts at Short Contact Times
… dehydrogenation rates. H2 addition tests show a two zone model; preferential oxidation to H2 raising the catalyst temperature while preserving C2H6, followed by C2H4 production. On Rh, H2 addition produced minimal change. The differences in catalytic performances are attributed to the high …
-
Size Controlled Metal Oxide Nanoparticles:Synthesis, Characterization, and Application to Catalysis
… yields. Sooting combustion was performed using a two-zone flow reactor with precise control on experimental parameters. Gas suspended metal oxide nanoparticles were generated by burning off the organic backbone of the dendrimer-metal complexes in zone 1 and immediately transferred to zone 2, where …
-
An investigation into the influence of autoignition chemistry and charge cooling under 'Beyond RON' operating conditions on the improved knock resistance of ethanol over iso-octane
… conditions that the fuels were exposed to. A two-zone zero dimensional combustion model with an empirical knock model was implemented to study the influences of differences in inlet air cooling and autoignition chemistries on the knock resistance. The modelling study showed that the …
-
Exergy Based SI Engine Model Optimisation. Exergy Based Simulation and Modelling of Bi-fuel SI Engine for Optimisation of Equivalence Ratio and Ignition Time Using Artificial Neural Network (ANN) Emulation and Particle Swarm Optimisation (PSO).
… upon exergy analysis. An artificial neural network (ANN) is used as an emulator to speed up the optimisation processes. Constrained particle swarm optimisation (CPSO) is employed to identify parameters such as equivalence ratio and ignition time for optimising of the engine performance, based …
-
Dynamic modeling and global optimal operation of multizone variable air volume HVAC systems
… optimal operation of HVAC and building systems. Two different dynamic models of a multizone variable air volume (VAV) system have been developed using (i) bottom-up and (ii) top-down approaches. The models take account of the dynamic interactions between building shell, VAV system components and …
-
An investigation to determine the complexity and feasibility of combustion & NOx modelling in modern GTDI engines
… to predict NOx production in a GTDI engine using two zone combustion modelling and a variation of what is typically referred to as the “Zeldovich” model. The investigation assessed 3 collective data sets from two Ford Motor Company EcoBoost engines, their 4-cyl 1.5L and their 3-cyl 1L. With the …
Page 1 of 2