Applied Mechanics and Materials Vol. 822

Abstract: One between fundamental problems of mechanical engineering are accordingly to available energy from nature after an adequate modification at a certain point where is using to generate a practical operation. Sonique theory establish by romanian scientist George Constantinescu is one of the method who permit this operation. This paper is demonstrating possibility for using mechanical power-transmission through sonique and ultrasonique waves in heating systems, in economic advantages conditions. Applications of this theory is to generate heat with sonique and ultrasonique waves, and pass over (send forward) through cold pipes, and heating only sonique resistance at wished place

Abstract: In this paper is presented a new parametric finite elements model of SERB-194C [1] device which is used in protecting the civil engineering structures during earthquakes by limitating the drifts of building stories and dissipating the energy received by the building structure during the earth surface shaking. The goal of this simulation is to determine the influence of the device components dimensions on the variation of forces-displacements device curve. Modifying the device components dimensions, the force-displacements device curve is changing the shape and the area which are related with the capacity of building drift limitation of SERB-194C device. By changing the hysteretic loop shape and dimensions this device can be optimized for different buildings and structures in order to properly diminish the story drift during ground shaking.

Abstract: This paper presents the three-dimensional geometric modeling of the knee prosthesis components using the latest generation of CAD-CAE applications as DesignModeler and SpaceClaim under Ansys Workbench software package. The mesh generation and the contact conditions are presented. The parameterized virtual models of the knee prosthesis allow different changes in shape or dimensions which can lead to the optimization of the implant and of the biomechanics of the prosthetic knee.

Abstract: This paper analyse the performance of two types of devices used for protecting the building against collaps during earthquakes. These devices are used in paralell with the base isolation system of the building and are intended to increase the damping phenomenon in order to dissipate the quakes energy received by the resistance structure of the buildings. The purpose of this computational study is to determine if these friction dampers, which are four times less expensive than the classical viscous fluid dampers, can replace the classical choice in order to obtain a less expensive protection. The results obtained at the final of this study are encouraging because the damping performances of romanian telescopic devices are similar with the performances of classical viscous fluid devices in base isolation system.

Abstract: In the first stage of research, real bone components were analyzed to determine the main visual geometric shapes. After that, it was used a CT or MRI device to get parallel sections of studied bone components. In the third stage, the images were transferred to a 2D CAD software like AutoCAD, where the outer and inner contours of the bone were approximated by polygonal lines composed of multiple segments. To obtain virtual bones was used a parametric CAD software that allows defining models with a high degree of difficulty. The contours were transferred to a 3D CAD software, which, step by step, each section was used to define each virtual component of bone. For some components, such as vertebrae, bones of the jaw, the skull bones, was used in a preliminary model consists of curves in parallel planes. Based on this model can be defined the main curves for the final virtual 3D solid model. Also, were defined innovative orthopedic metal components as tibia nail, plates and screws or prosthetic elements. Were defined simulations to determine the behavior of the new orthopedic models through FEA method.

Abstract: The automotive industry represents one of the most important segments of the world economy that has to be in a continue development. The latest procedures for determination of an internal combustion engine performance have a big acquisition cost and demand special conditions even if the tested engine has smaller dimensions. The present paper presents other accessible solutions for this matter.

Abstract: In this paper, we submit an advanced solution for the optimization of the supercharging process in the engines that are experimentally researched on the test bench. This solution may be applied only to the engines set on the test bench, whose energy, economic or ecological performances require an impetus by the optimization of the supercharging process. Cutting-edge automatic equipment for the achievement of the supercharging process should be used, with a view to studying and improving the behaviour of the experimentally researched engines, depending on the intensity of the supercharging process. In this way, the parameters to be fulfilled by the supercharging aggregate, which will equip the internal combustion engine, during its exploitation, will be known.

Abstract: Alcohols begin to show a real interest for their use as fuel at compression ignition engines due to require reducing the pollutants emissions, especially NOx emission. Among the primary alcohols, butyl alcohol (butanol) is considered to be of great perspective in its use as fuel in diesel engines due to its properties close to those of diesel fuel. It is miscible with the diesel fuel and the achieved blend is stable. In paper are presented some aspects regarding the diesel engine’s fuelling with butanol and diesel fuel blends using the experimental research and numerical modelling. The use of the butanol as a fuel for diesel engine has led to the reducing NO_x emissions with about 25% and the Brake Specific Energetic Consumption (BSEC) with about 5% at the full load and the maximum torque engine speed.

Abstract: The use of bioethanol as alternative fuel for automotive supercharged spark ignition engines is required especially for to respect the pollutant norms which become more and more severe, especially for NO_x emissions.The general objective of the researches is improving of a automotive supercharged spark ignition engine efficiency, improving performance of power and torque and decreasing of the emissions level by the use of bioethanol. Bioethanol is so a very good alternative fuel for SI engines because of its better combustion proprieties comparative to the gasoline as a good cooling agent of the intake air due to its high vaporization heat.The paper presents results of some theoretical and experimental investigations on a 1.5 L supercharged SI engine fuelled with gasoline-bioethanol blends. The investigations show that the improvement of the combustion process by use the bioethanol at the supercharged spark ignition engine leads to the reduction of BSFC, to the accentuated reduction CO and HC due to a lower C content and better combustion properties of the bioethanol. In same time, the NOx emissions level significantly decreases because of the local cooling effect produced by bioethanol vaporization.

Abstract: The increasing price of the fuels and tightening of the pollution rules requires the use of some efficient fuelling methodes with altenative fuels for diesel engines. Fuelling with LPG of a diesel engine is a viable sollution, considering that it can be used the infrastructure for distribution and storage already used for spark ignition engines. In this work are presented results of theoretical and experimental investigations of a truck diesel engine fuelled with LPG by diesel-LPG methode. The main objective research is the decrease of the nitric oxides emissions with the premise that the engine power is maintained at the same level like in the case of the standard engine, fuelled only with diesel fuel.