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It is proposed a study to evaluate PHP (pulsating heat pipes) device application in battery thermal management systems for HEV (hybrid-electric vehicle) and EV (electric vehicle). Firstly, it is necessary to understanding Li-ion (lithium ion) batteries for HEV/EV, the electrical energy supply state-of-the-art. The analyzed aspects were battery framework and configuration; working principles and mechanisms; and market penetration and potential. Secondly, the adverse effects of temperature over such batteries were discussed. After understanding the case study, a battery modeling survey was performed in order to later evaluate BTMSs (battery thermal management systems). Well comprehended case study and battery modeling, then, it was possible to examine current automotive battery cooling and heating solutions.

A hydraulic accumulator used in gear selection phase of an automated manual transmission was studied to employ simulations which could predict response time of entire system. A spring-mass-damper mathematical model was created from real data and response time measured in acquisitions of a first prototype system built. The model objective was to determine values for damper coefficient and spring mass rate to be used in the design of a pair of springs with enough stiffness to achieve system response time desired. With prototype data and mathematical model developed, predictions about response time of a final system were performed and a spring rate value was determined to satisfy with response time requested. From model data, numerical structural analyses were performed in order to predict eventual final system failures due to the stiffness values involved.

The crankshaft is one of the most important moving components of an internal combustion engine. It is responsible for transforming the oscillating piston movement into rotating movement by the connecting rods. During engine running, the crankshaft is submitted to axial, bending and torsional loads, which results in high stressed regions on the component. Due to the phased cylinder combustions, the crankshaft has high levels of torsion loads and the excessive torsional vibration is one of the main causes of failures in crankshafts and engine accessories, as pulleys, belts and gears. This paper presents an analytical method for previewing the crankshaft stresses by considering the component as simple a cylindrical shaft, applying the radial and the torsional loads on the crankpins and supporting at the main bearing positions.

The understanding of how mechanical stresses influence in the behavior of automotive components is of great interest to the automotive industry. The design of products must be made considering these efforts, always aiming to ensure smooth operation and no failures. To learn more about these efforts, a finite element simulation can be done. However, the results obtained from these simulations must be confirmed by carrying out physical experiments. Many methods are available to obtain the stress/strain fields of the object been tested, among which the best known and widespread is the use of strain-gauges. This technique requires a relatively long time of preparation as well as several measurements to obtain the full stress/strain field. The laser interferometry technique, on the other hand, reduces considerably the testing time to obtain the full stress/strain field, and no intervention on the object is required.

The scope of this paper is the study of the crankshaft fatigue strength under bench tests loads. When a crankshaft is running inside the engine, it is subjected to radial forces and torsional moments. These radial forces come from the fuel combustion and are responsible for the crankshaft bending. The moments occur mainly due to the torsional vibration phenomenon and are responsible for twisting the component. Once there are these two main loads which can damage the component, both must be considered in the design phase. Moreover, the crankshafts must be tested under these conditions to guarantee that they will not fail during engine operation. The finite element method is used to simulate the bending and torsional experimental tests before the crankshafts manufacturing. Fatigue calculations are performed using simulation results to predict how the crankshafts will fail on the experimental bench tests.

Nowadays, there is a demand for ICE (Internal Combustion Engines) with higher PCP (Peak Cylinder Pressure) in order to improve the engine performance and decrease the level of emissions. Due to this PCP increasing, the engine components must have higher structural strength. This work aims to perform a structural investigation of an innovative and revolutionary non-straight bearing applied to the pin journal of a crankshaft for a mid-range application (called U-Shape bearing). By using of structural optimization tools applied to this non-conventional bearing it was achieved substantial reduction of the stress concentration in the pin fillet and also substantial improvement in the crankshaft torsion stiffness, which results in a better dynamic performance regarding torsional vibration and potential for better NVH behavior.

The main focus of this work is to study variable compression ratio engines. The study begins with an analyze of the benefits of a variable compression ratio for Otto Cycle engines including mechanisms that already exist, the usual constructive solutions and the project criteria adopted in the area. The kinematic and dynamic model of SVC Saab mechanism, using Newton-Euler equations, is developed. Also, the cylinder pressure curve is important to be determined. The pressure curve and the cylinder volume function will be evaluated analytically considering the variation of the compression ratio. Furthermore, in order to know the influence of the design parameters in kinematic and dynamic, some sensitivity analysis of the engine mechanism will be performed. Finally, a computational implementation of the engine mechanisms analyzed will be done in Matlab language. This implementation includes the crank mechanisms and its kinematic and dynamic analyzes.

There has been an increasing interest of the automotive industry for making lighter and more efficient mechanical components. Based on that, fuel consumption, pollutant and cost reductions may be achieved. In this work, three different methodologies for kinematical and dynamical analyses of the crank mechanism of internal combustion engines are developed. The first model is the traditional method and is widely used by the automotive industry due to its simplifying assumptions, which avoids the calculation of the connecting-rod inertia moment. The second uses the Newton-Euler equations for a system of multiple rigid bodies, considering the piston as a material point, while the connecting-rod and crank are treated as rigid bodies. The third model employs the software RecurDyn, which uses the recursive dynamic concept. We compare the models based on results of their kinematical and dynamical behavior, defining their similarities and differences.