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Detailed computational fluid dynamics models of mineral insulated metal sheath thermocouples are discussed, and thermocouple readings in clean flames are verified against experimental thermocouple data for a Hencken burner flame available in the literature. Computational results present thermocouple temperature readings as a function of thermocouple insertion depth in threedimensional directions. Computational temperature correlations are plotted against nondimensional insertion depth and insertion height above the burner. Overall predictions showed excellent agreement with experimental data...
Three-dimensional numerical computations have been carried out to investigate the dynamics inside proton-exchange membrane fuel cell (PEMFC) and its performance using STAR-CD solver, the computational fluid dynamics software. Theoretical results in polarization curves quantitatively corroborate the experimental findings previously reported in Jung et al. Also, effects of various process conditions such as relative humidity, stoichiometric ratio at anode and cathode channels, and cell configuration on the performance of fuel cell have been further scrutinized. It has been revealed that the...
Two different medium-speed diesel engine cylinder head designs have been studied. The focus of the study has been the effect of intake channel design in the in-cylinder flow. The study has been carried out by CFD. The first cylinder head is a standard Wärtsilä 20 cylinder head and the second one is a specially designed head for a single cylinder research engine, called Extreme Value Engine (EVE). The CFD boundary conditions have been simulated by the help of a 1-d simulation code. In the full load cases the maximum cylinder pressure was 300 bar. Simulations have been done at lower load level...
In order to increase engine capacity of close-deck single-bore type engine blocks, bore diameter is usually enlarged that results in thinner intra-bore sections. Enlarged intra-bore sections affect thermal loads around the cylinders as well as manufacturing complexities due to thinner water jacket cores. As a possible remedy, intrabore cores can be removed and passages can be created in the intrabore region by multiple drills. However, it should be ensured that sufficient heat transfer from ring reversal area is possible and effect on bore distortion is acceptable. The second item is...
The economic recession, the environmental impact as well as the continuous fossil fuel consumption encourage actions that focus on saving energy. In the vessels sector, one of the main objectives has always been to reach a hydro-dynamically optimum hull which gave the desired speed with minimum power.Hydrodynamic drag is basically divided into two parts: a) the friction between the water and the hull,and b) the wave generation due to the free-surface air-water. Presented in this paper, is the research which evaluates the possibility of friction-drag reduction by means of the coat of special...
Background: Wall shear stress (SS) plays an important role in the initiation and proliferation of coronary atherosclerosis, especially for bifurcations. Stenting in the coronary artery will cause many different changes in velocity, flow, cross-sectional area, and especially the wall SS. However, it is still unknown how much wall SS distribution varies with stenting in coronary bifurcation. Objective: The purpose of this study was to investigate the magnitude and distribution of wall SS after the classical crush stenting for bifurcation lesions. Methods: Eleven patients with true coronary...
Jet ignition and direct fuel injection are potential enablers of higher efficiency, cleaner Internal Combustion Engines (ICE). Very lean mixtures of gaseous fuels could be burned with pollutants formation below Euro 6 levels (in the ultra-lean mode), efficiencies approaching 50% full load and small efficiency penalties when operating part load. The lean burn Direct Injection Jet Ignition (DI-JI) ICE uses a fuel injection and mixture ignition system comprising one main chamber direct fuel injector and one small size jet ignition pre-chamber per engine cylinder. The jet ignition pre-chamber is...
This paper presents recent advances in the development and integral validation of a two-phase Computational Fluid Dynamics (CFD) computer model (CFDBWR) that allows the detailed analysis of the two-phase flow and heat transfer phenomena in Boiling Water Reactor (BWR) fuel bundles. The CFD-BWR code is being developed as a customized module built on the foundation of the commercial CFD-code STAR-CD which provides general two-phase flow modeling capabilities.
This paper presents the efforts done by Volvo 3P, through a partnership with ThermoAnalytics Inc, to develop transient thermal simulation methodologies of the under hood of a truck. The verification process for the hot spots analysis currently in use at Volvo 3P is described and the key transient situations for the hot spots analysis are identified: hot shutdown, DPF regeneration and long drive cycle, are currently only covered by physical testing late in the project, contrary to steady-state operating conditions that are already managed through simulations in the early stage of the...
An advanced simulator is newly developed to predict fly ash modification behavior by direct injection of Ca fine particles in coal combustion furnaces. The Ca fine particles are a by-product of cement manufacturing process. This simulator is built on the coal combustion/gasification module based on the commercial Computational Fluid Dynamics (CFD) software of STAR-CD V3.26. Regarding the fly ash modification reaction model, it is based on the solid particle coagulation model. We improve this coagulation model to apply the fly ash modification reaction. The parameters of this particle...

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