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The engine valve spring is a very important component in automotive engine systems. The non-metallic inclusions in an engine valve spring will significantly reduce its reliability. In this study, an attempt was made to establish a correlation between fatigue failures and non-metallic inclusions by applying statistical methods. Fatigue tests with BZ and OTEVA-90 materials are performed with two different types of experiments, which are rotating bending fatigue test (Nakamura test) and spring fatigue test. By using RELIASOFT, the data of these two tests are analyzed with the Weibull distribution in order to statistically estimate BZ and OTEVA-90's fatigue lives at 90% low confidence under different stresses. On the other hand, fatigue strength of these materials can be estimated by Murakami and Endo's model with maximum inclusion size predicted from the Gumbel distribution.

This work aims to numerically investigate the aerodynamic characteristics of a multi-element airfoil NACA 23012. The investigation was conducted through Computational Fluid Dynamics (CFD), using ANSYS FLUENT software. The Navier-Stokes equations were solved for turbulent, incompressible flow using k-epsilon model and SIMPLE algorithm. The study was carried out for both take-off / landing conditions and the results were compared to experimental data of the NACA 23012 from wind tunnel tests. The experimental and computational results for drag and lift coefficients match effectively up to pre-stall attack angles. The pressure coefficients, velocity distribution, and wall Y+ data were presented for different angles of attack (0 deg, 4 deg, and 8 deg). The CFD analysis could help acquire a closer and detailed understanding of airfoil performance, which is usually not easy through normal experimentation.

In this study three dimensional numerical simulations were carried out for steady incompressible flows around complex airfoil shapes. NACA-0012 and NACA-23012 wing with 20 percent-c Clark Y flap were used for this study. This work shows that the CutCell mesh method has the ability to generate high quality mesh which captures the details of the viscous boundary layer.

The power and torque output of an engine (for a Formula SAE vehicle) can be dramatically improved through good intake design. For example, performance can be improved by reducing pressure losses in the intake system, or by improving the restrictor's design to increase airflow at lower pressure drops. A plenum design with equal air distribution to all cylinders can also be helpful. In this study, four different intake designs were tested on a dynamometer and the power outcomes were compared. Based on theory and lab testing and intake system was designed to optimize throttle response as well as low-end torque; a steady flow of air passes through the throttle body and the restrictor and then into the plenum. Dynamometer testing confirmed an overall increase in torque and horsepower compared to earlier designs.

This work studies an optimization tool for 2D and 3D a multi-element airfoil which utilizes the power of CFD solver of a Shape Optimizer package to find the most optimal shape of multi-element airfoil as per designer's requirement. The optimization system coupled with Fluent increases the utilization and the importance of CFD solver. This work focuses on combining the high fidelity commercial CFD tools (Fluent) with numerical optimization techniques to morph high lift system. In this work strategy we performed morphing (grid deformation) directly inside the Fluent code without rebuilding geometry and the mesh with an external tool. Direct search method algorithms such as the Simplex, Compass, and Torczon are used; Navier-Stokes equations were solved for turbulent, incompressible flow using k-epsilon model and SIMPLE algorithm using the commercial code ANSYS Fluent.

Investigations were conducted on how to improve vehicle performance by improving throttle response. A method for improving throttle response was to reduce the rotating and reciprocating mass in the engine. Two engines, which only differed in the amount of rotating and reciprocating mass, were investigated. Based on tests on a chassis dynamometer, it was observed that there was an 18% faster throttle response for the engine possessing the lower amount of rotating and reciprocating mass.

In the present work, the effect of various nanofluids on convective heat transfer performance in an automotive radiator was analyzed based on measured nanofluid properties. Al2O3, TiC, SiC, MWNT (multi-walled nanotube) and SiO2 nanoparticles ranging between 1 and 100 nm in size were dispersed in distilled water to form nanofluids. An ultrasonic generator was used to provide uniform particle dispersion in the fluid and keep the mixture stable for a long period of time. The impact of various particle types and their volume concentration on fluid properties such as density, thermal conductivity and viscosity were experimentally analyzed. It is observed that the nanofluid properties increased with the increase in particle volume concentration. TiO2 nanofluids were observed to show the highest increase in density (2.6% higher than the base fluid at a 1% vol. concentration) and also the largest enhancement in thermal conductivity (7.5% augmentation at 1% concentration).