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Currently in the automotive industry it is indispensable the evolution of technology applied in the design and manufacturing of components, either for a specific performance improvement or even as part of a cost reduction plan. For these main reasons, it has been constantly invested in methods that may help engineers to understand the dynamic efforts to which the components are submitted. In order to determine the loads suffered by the steering system of a vehicle in motion, the Group of Automotive Technology from the Lutheran University of Brazil (also known as “GTA”) conducted tests using a front-wheel drive road vehicle with a 1.4L transverse engine. The steering column (which joins the steering wheel to the steering gearbox ) and the tie rod (which connects the steering rack to the steering knuckle) were used as elastic elements to form load cells by the attachment of resistive strain gages in a full Wheatstone bridge.

Recent measurements and models show that the soot distribution and the permeability of the soot layer depend on the selected engine operating points both while loading and during regeneration. The influence of an upstream oxidation catalyst on the soot distribution has been shown. Most interestingly, a radial velocity profile has been observed by an optical measuring technique. However, in actual practice only the overall pressure drop due to the thousands of parallel channels of a wall flow filter is measured. In order to find out experimentally whether or not aging and thermal instability of diesel particle filter correlate with inhomogeneous flow conditions a simple set-up was developed to measure the outlet velocity profile. A Prandtl-tube with an inner diameter of 1 mm was scanned in x- and y-direction across the outlet channels of a catalytically coated wall flow filter, which was attached to a blower. The settings of its electro motor were kept constant in all the experiments.

This paper provides information on measurements and measurement techniques for particulate and unburnt hydrocarbon emissions from diesel engines. A dilution mini-tunnel was used to characterize the effects of the dilution ratio and sample temperature on the total particulate mass and soluble organic fraction(SOF) constituents. Increasing the sample temperature resulted in changes in the polynuclear aromatic hydrocarbon(PAH) constituents in SOF. The SOF was isolated by column chromatography, and the PAH fraction was determined by high performance liquid chromatography(HPLC). Column chromatography with silicagel, an octadecylsilan-bonded column, and keeping at high temperatures improved the analytical efficiency of HPLC. The gaseous hydrocarbon in raw exhaust was analysed by GC with FID. The temperature of the sample glass syringe affected measurements of high boiling point hydrocarbon constituents.

Measurement on turbulent premixed CH4/H2/air flames was studied experimentally. Hydrogen blending ratio is defined as the ratio of hydrogen to fuel, while CO2 dilution ratio is defined as the mole fraction of CO2 to those of mixture. Hydrogen blending ratios up to 0.2 and CO2 dilution ratios up to 0.1 were studied. OH profile of the instantaneous flame front was detected using the OH-PLIF visualizations on a turbulent Bunsen burner. 500 OH-PLIF images were used to obtain the turbulent burning velocity and calculate flame surface density, and 280 images was used to calculate the local curvature radius.

The use of damage tolerance analysis in the Aeronautical Industry have been required a most accuracy determination of the applied stress on component and assemblies. To obtain this, beyond the improvement in the stress calculation through finete element analysis, is very important the residual stress determination. This paper shows the adequacy of the hole drilling method to residual stress measuring in aluminum alloy 6061-T6 welded assemblies. In the component the residual stresses had reached values up to 130 MPa, being function of the fixture restraints during welding process. The heat treatment conditions of the stress relief were not effective into ranges that do not cause deletereous effect in the mechanical properties of 6061-T6 aluminum alloy.

This material presents a project for data acquisition applied to monitoring climatic road simulators. The developed system acquires accelerometers and thermocouple signals from the vehicle suspension and body, point-by-point. This implementation allows real-time monitoring during tests, with the objective of making is autonomous. The platform used for the data-logger and automation system is composed by analog and digital input/output, TCP/IP and OPC protocols. The result obtained by this approach consisted mainly on the possibility of mapping the vehicle response throughout the tests, the integration of climatic and vibration control and overall contribution to a higher use of road simulators.

This paper describes the ‘Measurement-Assisted Assembly’ activities led by the Final Assembly Line unit at Airbus - Toulouse. These activities are meant to eliminate some of the problems associated with the conventional process of locating and positioning large airframe sub-assemblies during the final assembly process, like fuselage-to-fuselage or wing to fuselage junctions. All these activities include laser or photogrammetry subsystems, computer-aided measuring systems, Best-Fit optimization software, specific Graphical User Interface. The combination of these technologies offers: jigless assembly, faster assembly process, rework and waste reduction and many more advantages.

To determine the power loss of hypoid gears often used as axle gears of vehicles a new test procedure has been developed. Hereby the power loss of the test rig can be directly measured using real application conditions. Measurements have shown that axle offset and lubricant have a big influence on the efficiency. Standardized efficiency tests especially for axle gears of passenger cars were worked out to determine the influence of lubricants. Hereby operating points representing common driving cycles are adjusted controled by a computer. These tests have shown that synthetic lubricants can increase the efficiency significantly at high torque.

A series of measurements was made of voltages induced in electrical circuits within a metallic aircraft wing by full-scale simulated lightning currents flowing through its skin and structure. The measured data were mathematically analyzed to enable determination of voltages across load impedances to which the circuits might be connected elsewhere in the aircraft. Relationships between induced voltages and lightning current, wing structural, and circuit parameters were determined. Induced voltages of magnitudes likely to cause damage or interference with avionics were measured.

The noise radiated from the tail pipe plays an important role in the total noise emitted for small two stroke engines. In this paper, an engine cycle and exhaust system model for a commercial 50 c.c., crankcase-scavenged type, single cylinder two stroke engine was developed to determine the noise emitted from the exhaust pipe. In modeling the engine cycle, a zero dimensional thermodynamic model was used to represent the compression and the expansion process in cylinder, and a two zone quasi dimensional model was used to represent the combustion process. As for the scavenging process, the perfect mixing model was used. In modeling the gas dynamics in the intake and the exhaust system, an unsteady one dimensional model was used, and the characteristic line method was employed to solve the partial differential equations.

Multidimensional calculations and laser Doppler anemometry measurements are presented of the air flow in a research diesel engine motored at 900 rpm with a compression ratio of ∼8.5. The engine comprised the cylinder head of a Ford 2.5L high speed direct-injection diesel mounted on a single cylinder Fetter engine modified to provide optical access for LDA measurements in a toroidal piston-bowl. The accuracy of the predictions is assessed against ensemble-averaged velocity data and found to be sufficient to allow better understanding of the flow in production engine geometries under realistic operating conditions.

Minimizing heat-transfer (HT) losses is important for both improving engine efficiency and increasing exhaust energy for turbocharging and exhaust aftertreatment management, but engine combustion system design to minimize these losses is hindered by significant uncertainties in prediction. Empirical HT correlations such as the popular Woschni model have been developed and various attempts at improving predictions have been proposed since the 1960s, but due to variations in facilities and techniques among various studies, comparison and assessment of modelling approaches among multiple combustion modes is not straightforward. In this work, simultaneous cylinder-wall temperature and OH* chemiluminescence high-speed video are all recorded in a single heavy-duty optical engine operated under multiple combustion modes. OH* chemiluminescence images provide additional insights for identifying the causes of near-wall heat flux changes.

To observe the effect of engine applications on small engine design, bending and torsional stresses of a crankshaft were measured dynamically under various load conditions. A dynamometer and a generator were selected as the load sources, because these two devices can provide different load patterns respectively. As the results, the peak bending stresses at the crankshaft pin fillets of a dynamometer set engine were about 40∼60% larger than those of a generator set engine. Conversely, the peak torsional stress at a crankshaft journal of the dynamometer set engine was about 25% smaller than that of the generator set engine. To investigate the reasons of these differences. additional measurements and FEM calculations were carried out. Finally we found that the stiffness of the crankshaft support had a great influence on the value of the peak bending stress and the torsional stress was affected by the installation angle between the engine TDC and the rotor of the generator.

The residual gas in SI engines is one of important factors on emission and performance such as combustion stability. With high residual gas fractions, flame speed and maximum combustion temperature are decreased and there are deeply related with combustion stability, especially at Idle and NOx emission at relatively high engine load. Therefore, there is a need to characterize the residual gas fraction as a function of the engine operating parameters. A model for predicting the residual gas fraction has been formulated in this paper. The model accounts for the contribution due to the back flow of exhaust gas to the cylinder during valve overlap and it includes in-cylinder pressure prediction model during valve overlap. The model is derived from the one dimension flow process during overlap period and a simple ideal cycle model.

The battery efficiency is strongly affected by the operating temperature, granting the best performance in a limited range. Great attention is given to the design and the testing of materials for the battery heat dissipation. In the present study, the thermal behavior of a Li-polymer cell, which is part of a battery pack for electric vehicles, is investigated. The cell is provided with different coatings of carbon, graphene, and silicone, used in turn, to dissipate the heat generated during the operation in natural convection. The coating is placed only on one side of the battery while the other one is inspected via thermal imaging. Optical diagnostics in the infrared band are used to evaluate the bi-dimensional distribution of the battery surface temperature and the effect of the coatings. Different operating conditions are tested by varying the current demand.

The computational fluid dynamics codes, which help to predict the behaviour of combusting gas in reciprocating engines, need, as boundary conditions for the momentum and energy equations, to approximate wall frictions and heat transfer between gas and walls. The purpose of this work is to outline the physical parameters which affect the heat transfer in spark ignited engines, and then to validate a multidimensional model which takes these parameters into account. In an experimental study, measurements were made on a test-engine instrumented with fast-response surface heat flux gages. Each gage was made of a steel cylinder, containing two thermocouples. A laser doppler velocimeter was used to analyze the influence of fluid dynamics on heat transfer. Up to ten data inputs could be simultaneously recorded at each crank — angle, including the heat flux at four locations of the combustion chamber, two velocity components and the cylinder pressure.

A combined experimental and analytical approach was followed in this work to study stress distributions and causes of failure in diesel cylinder heads under steady-state and transient operation. Experimental studies were conducted first to measure temperatures, heat fluxes and stresses under a series of steady-state operating conditions. Furthermore, by placing high temperature strain gages within the thermal penetration depth of the cylinder head, the effect of thermal shock loading under rapid transients was studied. A comparison of our steady-state and transient measurements suggests that the steady-state temperature gradients and the level of temperatures are the primary causes of thermal fatigue in cast-iron cylinder heads. Subsequently, a finite element analysis was conducted to predict the detailed steady-state temperature and stress distributions within the cylinder head. A comparison of the predicted steady-state temperatures and stresses compared well with our measurements.

Laser Doppler velocimeter results are presented for the mean velocity and turbulence intensity measured in a motored research engine. The compression of complex bulk motions created during induction produces turbulence as the piston approaches top dead center. The turbulence field is shown to be isotropic but nonhomogeneous. A zero-dimensional computer simulation based on an averaged k-ϵ model is shown to adequately predict the decay of turbulence at a point in the flow after the production phase is completed. Cylinder pressure measurements were recorded for homogeneous stoichiometric combustion for a range of engine speeds and ignition locations. A two-zone (burned and unburned gases) thermodynamic model accurately predicts the measured pressure histories when the turbulence results determined from the motored tests are used to establish initial conditions for the combustion model.

High intensity discharge lights (HID) are the innovation step that is now beginning to penetrate in all car classes. Investigating drivers, all results show that the benefits are visible to them and positively accepted. The quantification of the improvements has yet been insufficiently examined. In this article some of the aspects will be highlighted.

Nowadays, acoustic comfort is an important consideration in the design and operation of airplanes. In this context, an alternative approach, Statistical Energy Analysis (SEA) allows the study of energy diffusion in vibro-acoustic systems in mid and high frequency regions. This present study aims to describe the vibro-acoustic characterization of a structure similar to an aircraft fuselage. Several SEA models were considered to compare the analytical formulations found in the literature with measurement data. Two classes of the panels were investigated: simple and ribbed-stiffened. In this regard, the revised model for computing the coupling loss factors was evaluated and the results gave a good agreement with measured data.