Automotive and Engine Technology最新文献

{"title":"Sequential lidar sensor system simulation: a modular approach for simulation-based safety validation of automated driving","authors":"Philipp Rosenberger,&nbsp;Martin Friedrich Holder,&nbsp;Nicodemo Cianciaruso,&nbsp;Philip Aust,&nbsp;Jonas Franz Tamm-Morschel,&nbsp;Clemens Linnhoff,&nbsp;Hermann Winner","doi":"10.1007/s41104-020-00066-x","DOIUrl":"10.1007/s41104-020-00066-x","url":null,"abstract":"<div><p>Validating safety is an unsolved challenge before autonomous driving on public roads is possible. Since only the use of simulation-based test procedures can lead to an economically viable solution for safety validation, computationally efficient simulation models with validated fidelity are demanded. A central part of the overall simulation tool chain is the simulation of the perception components. In this work, a sequential modular approach for simulation of active perception sensor systems is presented on the example of lidar. It enables the required level of fidelity of synthetic object list data for safety validation using beforehand simulated point clouds. The elaborated framework around the sequential modules provides standardized interfaces packaging for co-simulation such as Open Simulation Interface (OSI) and Functional Mockup Interface (FMI), while providing a new level of modularity, testability, interchangeability, and distributability. The fidelity of the sequential approach is demonstrated on an everyday scenario at an intersection that is performed in reality at first and reproduced in simulation afterwards. The synthetic point cloud is generated by a sensor model with high fidelity and processed by a tracking model afterwards, which, therefore, outputs bounding boxes and trajectories that are close to reality.</p></div>","PeriodicalId":100150,"journal":{"name":"Automotive and Engine Technology","volume":"5 3-4","pages":"187 - 197"},"PeriodicalIF":0.0,"publicationDate":"2020-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41104-020-00066-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50509044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal and prototype dimensioning of 48V P0+P4 hybrid drivetrains","authors":"Matthias Werra,&nbsp;Axel Sturm,&nbsp;Ferit Küçükay","doi":"10.1007/s41104-020-00071-0","DOIUrl":"10.1007/s41104-020-00071-0","url":null,"abstract":"<div><p>This paper presents a virtual toolchain for the optimal concept and prototype dimensioning of 48 V hybrid drivetrains. First, this toolchain is used to dimension the drivetrain components for a 48 V P0+P4 hybrid which combines an electric machine in the belt drive of the internal combustion engine and a second electric machine at the rear axle. On an optimal concept level, the power and gear ratios of the electric components in the 48 V system are defined for the best fuel consumption and performance. In the second step, the optimal P0+P4 drivetrain is simulated with a prototype model using a realistic rule-based operating strategy to determine realistic behavior in legal cycles and customer operation. The optimal variant shows a fuel consumption reduction in the Worldwide harmonized Light Duty Test Cycle of 13.6 % compared to a conventional vehicle whereas the prototype simulation shows a relatively higher savings potential of 14.8 %. In the prototype simulation for customer operation, the 48 V hybrid drivetrain reduces the fuel consumption by up to 24.6 % in urban areas due to a high amount of launching and braking events. Extra-urban and highway areas show fuel reductions up to 11.6 % and 4.2 %, respectively due to higher vehicle speed and power requirements. The presented virtual toolchain can be used to combine optimal concept dimensioning with close to reality behaviour simulations to maximise realistic statements and minimize time effort.</p></div>","PeriodicalId":100150,"journal":{"name":"Automotive and Engine Technology","volume":"5 3-4","pages":"173 - 186"},"PeriodicalIF":0.0,"publicationDate":"2020-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41104-020-00071-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50488319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A detailed study of a cylinder activation concept by efficiency loss analysis and 1D simulation","authors":"Thomas Buitkamp,&nbsp;Michael Günthner,&nbsp;Florian Müller,&nbsp;Tim Beutler","doi":"10.1007/s41104-020-00070-1","DOIUrl":"10.1007/s41104-020-00070-1","url":null,"abstract":"<div><p>Cylinder deactivation is a well-known measure for reducing fuel consumption, especially when applied to gasoline engines. Mostly, such systems are designed to deactivate half of the number of cylinders of the engine. In this study, a new concept is investigated for deactivating only one out of four cylinders of a commercial vehicle diesel engine (“3/4-cylinder concept”). For this purpose, cylinders 2–4 of the engine are operated in “real” 3-cylinder mode, thus with the firing order and ignition distance of a regular 3-cylinder engine, while the first cylinder is only activated near full load, running in parallel to the fourth cylinder. This concept was integrated into a test engine and evaluated on an engine test bench. As the investigations revealed significant improvements for the low-to-medium load region as well as disadvantages for high load, an extensive numerical analysis was carried out based on the experimental results. This included both 1D simulation runs and a detailed cylinder-specific efficiency loss analysis. Based on the results of this analysis, further steps for optimizing the concept were derived and studied by numerical calculations. As a result, it can be concluded that the 3/4-cylinder concept may provide significant improvements of real-world fuel economy when integrated as a drive unit into a tractor.</p></div>","PeriodicalId":100150,"journal":{"name":"Automotive and Engine Technology","volume":"5 3-4","pages":"159 - 172"},"PeriodicalIF":0.0,"publicationDate":"2020-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41104-020-00070-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50450849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement of the air-to-fuel ratio inside a passive pre-chamber of a fired spark-ignition engine","authors":"Nicolas Wippermann,&nbsp;Olaf Thiele,&nbsp;Olaf Toedter,&nbsp;Thomas Koch","doi":"10.1007/s41104-020-00067-w","DOIUrl":"10.1007/s41104-020-00067-w","url":null,"abstract":"<div><p>This paper investigates the local air-to-fuel ratio measurement within the pre-chamber of a spark-ignition engine by determining the absorption of light from hydrocarbons using an infrared sensor. The measurement was performed during fired and motored engine operation points and compared to the more common exhaust lambda measurements. The experiment provided data to compare the mixture preparation in a hot and cold environment of pre-chamber and main combustion chamber. The experiment also gives an indication regarding the possible use of a pre-chamber sensor in a motored engine at higher boost pressures and fuel mass flows, operation points that would overheat the sensor in a fired engine. The work also includes the analysis of the fuel delivery into the pre-chamber of a direct and indirect injection engine. Furthermore, pressure and temperature measurement within the pre-chamber provides information about the critical sensor environment and helps to understand the gas exchange between the two volumes.</p></div>","PeriodicalId":100150,"journal":{"name":"Automotive and Engine Technology","volume":"5 3-4","pages":"147 - 157"},"PeriodicalIF":0.0,"publicationDate":"2020-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41104-020-00067-w","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50517189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Concept of a torque sensor for simplex drum brakes","authors":"Christian Vey,&nbsp;Hermann Winner","doi":"10.1007/s41104-020-00065-y","DOIUrl":"10.1007/s41104-020-00065-y","url":null,"abstract":"<div><p>Several studies about the calculation of the brake factor exist, with differences in the degree of detail. One of the best known from Kößler is enlarged in this paper to analyze beside the brake factor the force inside the drum in further detail. Based on this analysis a relation between brake torque and abutment forces is presented, which leads to the idea of an abutment force sensor, to determine the brake torque. To assess this relation a sensitivity analysis is carried out. The results show a low sensitivity against the friction coefficient of the lining. The effects from all other, mainly geometric parameters are discussed to assess the potential of this innovative sensor.</p></div>","PeriodicalId":100150,"journal":{"name":"Automotive and Engine Technology","volume":"5 3-4","pages":"137 - 145"},"PeriodicalIF":0.0,"publicationDate":"2020-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41104-020-00065-y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50513250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A holistic consideration of turbocharger heat transfer analysis and advanced turbocharging modeling methodology in a 1D engine process simulation context","authors":"Marcel Lang,&nbsp;Thomas Koch,&nbsp;Torsten Eggert,&nbsp;Robin Schifferdecker,&nbsp;John P. Watson","doi":"10.1007/s41104-020-00062-1","DOIUrl":"10.1007/s41104-020-00062-1","url":null,"abstract":"<div><p>The focus on transient engine operation will increase to fulfill future emission requirements in the commercial vehicle sector. Accordingly, the transient turbocharger matching process is becoming increasingly important. The one-dimensional fluid dynamics (1D-CFD) simulation is established as an important development tool for matching the exhaust gas turbocharger to a combustion engine. The optimization of the modeling methodology of the combustion process and the turbocharger modeling are two key parameters to improve the reliability of the dynamic engine process simulation. In this paper, the advanced turbocharger (TC) methodology is described. This includes the determination of the adiabatic turbocharger performance from conventional hot gas test stand (HGS) measurement data, the derivation of an one-dimensional (1D) turbocharger heat transfer model and a method to physically extend the turbine map range. The adiabatic efficiencies of the turbocharger are determined with a model-based heat transfer correction of the conventional measured efficiencies from HGS measurement data. These adiabatic efficiency maps were used as a baseline to extend the conventional TC model with a heat transfer model taking into account of the engine boundary conditions in terms of temperature, pressure and mass flow rate. To assess the temperature distribution and the thermal inertia of the TC main components, in both stationary and transient engine operations, the variable geometry turbine (VGT) turbocharger hardware, installed on a medium-duty diesel engine, was equipped with several thermocouples on all accessible surfaces to make comprehensive surface temperature surveys. A 1D lumped capacitance heat transfer model (HTM) of the VGT TC was developed and validated against the experimental data from the engine test bench. To complete the advanced TC modeling, the turbine map is extended using experimental measurement data, based on extended HGS measurements, in combination with mathematically supported extrapolation. The results from the advanced turbocharger simulation methodology significantly improves the prediction of the temperature drop over the turbine in comparison to the conventional adiabatic TC simulation methodology. The validated heat transfer model also allows the analysis of the heat flow breakdown of the turbocharger. Based on the advanced turbocharger model, a tool for the improved transient turbocharger-engine matching process is given.</p></div>","PeriodicalId":100150,"journal":{"name":"Automotive and Engine Technology","volume":"5 3-4","pages":"113 - 136"},"PeriodicalIF":0.0,"publicationDate":"2020-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41104-020-00062-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50518294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of optimal rim and tire dimensions regarding load capacity, driving dynamics, and efficiency","authors":"A. Strigel,&nbsp;U. Peckelsen,&nbsp;H.-J. Unrau,&nbsp;F. Gauterin","doi":"10.1007/s41104-020-00064-z","DOIUrl":"10.1007/s41104-020-00064-z","url":null,"abstract":"<div><p>Tire development based on functional tire characteristics (FTC) makes it possible to objectify target values across all topics and thus contributes to a clear target agreement between tire and vehicle manufacturers. Developmental tires can be evaluated on the basis of test bench measurements, thereby decreasing development duration and financial costs. A major challenge is the ongoing tightening of conflicting targets as a result of legal and customer-related requirements. Depending on the rim and tire dimensions the characterization of these conflicting targets can be different. Therefore, when defining a tire portfolio in the early development phase, methods are required to allow an evaluation of the feasibility based on objective correlations. In this paper a method for determining the optimal rim and tire dimensions by considering the respective requirements is presented. First of all, the effects of the tire dimension on individual FTC concerning load capacity, driving dynamics and efficiency are quantified using regression models. Next, the FTC of different dimension configurations are estimated on the basis of a Monte Carlo sampling. Finally solution spaces of optimal dimension ranges are shown graphically.</p></div>","PeriodicalId":100150,"journal":{"name":"Automotive and Engine Technology","volume":"5 3-4","pages":"101 - 112"},"PeriodicalIF":0.0,"publicationDate":"2020-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41104-020-00064-z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50513818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fuel consumption potential of gasoline engines in an electrified powertrain: homogeneous and heterogeneous lean combustion in comparison","authors":"Alexander Rurik,&nbsp;Frank Otto,&nbsp;Thomas Koch","doi":"10.1007/s41104-020-00063-0","DOIUrl":"10.1007/s41104-020-00063-0","url":null,"abstract":"<div><p>This paper evaluates the fuel consumption of homogeneous and heterogeneous lean combustion in the WLTC test cycle. A lean combustion engine is combined with an electrified powertrain and the combustion processes are compared with each other. There is also a distinction with regard to the degree of electrification. First, investigations are carried out with an “engine in the loop” test bench. It turns out that, as expected, the best fuel consumption results can be achieved with heterogeneous lean combustion in combination with homogeneous lean combustion. In addition, it is shown that, in combination with P1 hybridization, low-load heterogeneous lean combustion becomes less important, but continues to contribute to an improvement in fuel consumption. Additionally, P1 hybridization increases the percentage of homogeneous lean combustion by 13%. Thus, the cycle fuel consumption is improved through electrification disproportionately for homogeneous lean combustion by 7.5%, for stoichiometric combustion by 6%. Furthermore, electrification contributes to reducing nitrogen oxide emissions by about 50% in the test cycle to 9 mg/km. The reduction can be achieved by shifting the load points from high loads with higher NOx raw emissions to lower loads with lower NOx raw emissions and by omitting heterogeneous lean combustion. In the second step, the combustion processes for two different engine displacements are compared in calculations. This allows further investigations. It turns out that, with increasing degree of electrification and decreasing engine displacement, heterogeneous lean combustion can no longer contribute to an improvement in fuel consumption and rather an expansion of homogeneous lean combustion at high loads becomes necessary. In general, thanks to the electrification of the powertrain in combination with lean combustion, the cycle fuel consumption can be greatly reduced by up to 33% to 3.76 l/100 km. Electrification does not compete with the advantages of lean combustion, but complements them. The presented results show the potential for improvement in fuel consumption for future developments in gasoline engines in hybridized powertrains.</p></div>","PeriodicalId":100150,"journal":{"name":"Automotive and Engine Technology","volume":"5 3-4","pages":"91 - 100"},"PeriodicalIF":0.0,"publicationDate":"2020-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41104-020-00063-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50496227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis and characterization of the friction of vehicle body vibration dampers","authors":"Fridtjof Körner,&nbsp;Ralph Mayer","doi":"10.1007/s41104-020-00060-3","DOIUrl":"10.1007/s41104-020-00060-3","url":null,"abstract":"<div><p>The friction at the contact surfaces of a vehicle body vibration damper, which are moved relatively to each other, influences its transmission behavior at the start of movement (breakaway force) as well as with excitation signals of higher velocity and thus has an impact on the comfort properties of the damper. According to Vibracoustic (Die wichtigsten Kriterien für deutsche Autofahrer beim Autokauf, Springer Fachmedien Wiesbaden GmbH, Wiesbaden, 2019), for most German drivers (63%) comfort (in addition to brand and appearance) before driving dynamics (53%) and environmental compatibility (48%) is the most important criteria when evaluating a new car, which explains the importance of this vehicle characteristics. Furthermore, the friction is present with any relative movement of the damper and is, therefore, relevant for the design of the damper and the associated vertical dynamics. The friction is generally determined in the fully assembled state of the damper, including oil filling and gas pressure at a very low movement velocity to eliminate the influence of the damping force. This measurement method allows no or only inadequate statements about the friction behavior at, e.g. more dynamic excitation scenarios. As a result, the aim should be to characterize the friction properties without the influence of hydraulic damping at the start of movement or reversal of movement, as well as at higher movement velocities. Another goal is to evaluate the influence of the internal pressure of the damper on its friction behavior. The test damper used here is a commercially available monotube damper that has been modified in accordance with the requirements for these tests. The results shown below can be used as starting variables for further investigations for the targeted optimization of the friction properties and thus for the improvement of driving comfort. The reduction in damper friction promises an increase in comfort due to the improved decoupling of the vehicle body from the road excitation. Furthermore, the data obtained enable the level of detail of simulation models to be increased and serve as a basis for comparing different friction pairings and contact surfaces in the damper. For the substitution of coatings (chrome-free piston rods → environmental protection) or tube materials (aluminum matrix composites → lightweight construction) as well as for changes in the surface structure and roughness, the results enable an evaluation of the friction properties compared to conventional dampers and the adjustment of the friction pairings in the sense of the best possible functionality.</p></div>","PeriodicalId":100150,"journal":{"name":"Automotive and Engine Technology","volume":"5 3-4","pages":"79 - 90"},"PeriodicalIF":0.0,"publicationDate":"2020-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41104-020-00060-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50475286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strategy and potential of homogeneous lean combustion at high load points for turbocharged gasoline engines with direct injection and small displacement","authors":"Alexander Rurik,&nbsp;Frank Otto,&nbsp;Thomas Koch","doi":"10.1007/s41104-020-00061-2","DOIUrl":"10.1007/s41104-020-00061-2","url":null,"abstract":"<div><p>In this paper, a homogeneous lean combustion concept for gasoline engines with direct injection, small displacement and turbocharging is investigated under high-load conditions. A representative operating point was selected for this purpose. The tests were carried out on a single-cylinder research engine. In particular, the influence of the center of combustion, charge motion and pressure ratio is discussed. It has been discovered that the center of combustion has a large influence on the stability of homogeneous lean combustion at high load points. The present investigations provide a method of how to achieve an early center of combustion in knock-limited load points of homogeneous lean combustion. Early centers of combustion enable a high air–fuel ratio with good, smooth running and low NO_<i>x</i> emissions. In addition to the high charge motion, operation with a positive scavenging gradient and valve overlap can be applied to flush the hot internal residual gas out of the combustion chamber, whereby knocking can be reduced. With the high air–fuel ratio, specific fuel consumption can be reduced substantially and high combustion efficiency can be achieved. The results can be leveraged as a basis for future developments in gasoline engines.</p></div>","PeriodicalId":100150,"journal":{"name":"Automotive and Engine Technology","volume":"5 3-4","pages":"71 - 77"},"PeriodicalIF":0.0,"publicationDate":"2020-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41104-020-00061-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50463919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}