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A three-dimensional stream bed scour modeling methodology was developed using well-benchmarked commercial Computational Fluid Dynamics (CFD) software to compute the bed shear stress distribution used to calculate bed displacements and to re-mesh the computational domain as the bed is displaced. This study extends a previously developed two-dimensional iterative scouring procedure to predict the final shape and size of the scour-hole under pressure-scour flow conditions for flooded bridge decks using commercial CFD software. The current approach uses single phase flow models with an assumed...
This master thesis work has been conducted at the research institute for automotive engineering and engine technology Stuttgart (FKFS), with the virtual engine development team. Its main purpose is to give the customers of projects and advanced analysis solutions, through 3D-CFD tools. Nowadays, the computational fluid dynamic applied to the optimisation of engines have arose a leading role in the thermal design of powertrain systems, to compare different layout solutions with reduced prototyping costs. These kinds of simulations are in facts very required, since they can interact with the...
A complete methodology for the thermo-mechanical analysis of optical devices for the automotive industry is presented. The objective is to predict the thermal field all over the lamp,highlighting the zones with risk of melting, and the deformations and stresses associated with it. The proposed approach is based on a Computational Fluid-Dynamic (CFD) simulation capable of capturing all the heat transfer phenomena occurring inside and outside the lamp:conduction between different components of the device, natural convection associated with density changes in air (buoyancy effects), and...
A complete methodology for the thermo-mechanical analysis of optical devices for the automotive industry is presented. The objective is to predict the thermal field all over the lamp, highlighting the zones with risk of melting, and the deformations and stresses associated with it. The proposed approach is based on a Computational Fluid-Dynamic (CFD) simulation capable of capturing all the heat transfer phenomena occurring inside and outside the lamp: conduction between different components of the device, natural convection associated with density changes in air (buoyancy effects), and...
A 2200 cc engine head for marine applications has been analysed and optimized by means of both fluid-dynamic and thermo-structural simulations. First, the fluid distribution within the cooling jacket has been deeply investigated, in order to point out critical aspects of the current jacket layout and propose modified gaskets aiming at modifying the coolant path and increasing the cooling performance. A new generation polyhedral grid has been employed to combine high resolution surface spacing, computational demand, and numerical stability of the CFD simulations. Different turbulence models...
A 3D integrated numerical model is constructed to evaluate the thermal-fluid behavior and thermal stress characteristics of a planar anode-supported solid oxide fuel cell (SOFC). Effects of anode porosity on performance, temperature gradient and thermal stress are investigated. Using commercial Star-CD software with the es-sofc module, simulations are performed to obtain the current–voltage ( I–V ) characteristics of a fuel cell as a function of the anode porosity and the temperature distribution within the fuel cell under various operating conditions. The temperature field is then imported...
The requirements for performance by planetary exploration missions are increasing. Landing at a single location to take data is no longer sufficient. Due to the increasing cost, the missions that provide mobile platforms that can acquire data at displaced locations are becoming more attractive. Landers have also had limited range due to power limitations, limited lifetime of subsystems and the inability to negotiate rough terrain. The Center for Space Nuclear Research has designed an instrumented platform that can acquire detailed data at hundreds of locations during its lifetime—a Mars...
This paper describes the updating of the sub-cooled boiling model with the more recent and better sub-models. The improved sub-models include: Hibiki and Ishii correlation for nucleation site density, Kocamustafaogullari correlation for bubble departure diameter and the S-gamma model of Lo and Rao for bubble size distribution in the flow. The new model has been tested against measured data from Debora and Bartolomei . The results show that improvement in the bubble size prediction has the most significant impact on the accuracy of the model.

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