Automotive Science and Engineering

Numerical Investigation of the Effect of Cooled EGR on Turbocharger HCCI Engine Performance Fueled with Methane

T. OUKSEL

Optimization of Exhaust System Hangers for Reduction of Vehicle Cabin Vibrations

M.H Shojaeifard

Excitations from the vehicle engine and the road surface cause vibrations in the exhaust system and the exhaust noise and vibrations are transmitted through the vehcile body and structure to the cabin, causing distractions and discomfort for the driver and passengers. In this article the method of average driving degrees of freedom displacement (ADDOFD) has been used to determine and optimize the location of suspended hanger points. Based on this approach, a model of car exhaust system is used using ANSYS software to optimize the hanger installation points for reducing vibration and to select the best positions for these points. The optimum hanger positions must have a relatively lower ADDOFD value compared to adjacent points. Then the static and dynamic analysis of the exhaust system is illustrated and finally on the basis of the above analyses, the position is chosen for the exhaust system hangers to reduce the transmission of noise and vibrations into the car cabin. Results indicate that optimization of the locations has resulted in a significant decrease in hanger loads, significantly reducing the vibrations transmitted to the vehicle cabin and increasing the life of the rubber hangers. This study has practical significance for reducing the vibration of automobile exhaust systems and the vehicle cabin.

A new approach for Modeling and Evaluation of efficiency and power generation in Sterling engine; Analytical study

H. Saberinejad

Although, the Stirling engine (SE) was invented many years ago, the investigation on SE is still interesting due to variety of energy resources can be applied to power it (solar energy, fossil fuel, biomass and geothermal energy). In this paper, the thermodynamic cycle of SE is analyzed by employing a new analytical model and a new method is presented to evaluate output power and efficiency of real engines. Using the correcting functions; represent more accurate results for known Schmidt equations respect to adiabatic model. So without need to employing numerical methods and iterative solver programs, analogous results with accuracy and correctness of open-form solution-adiabatic method is obtained. The modeling of results of two methods is done by Non-linear Multiple Regression and new equations based on Schmidt equations with new correctness factors is presented. The correctness factors are function of structural and operational characteristics of engine. Moreover, available output data of GPU-3 SE was compared. These comparisons show good agreement, indicating that the model is an appropriate method for modeling of SE outputs.

A biomechanical modeling of an automotive passenger body to investigate the vertical vibration in various road profiles using transmissibility analysis

J. Marzbanrad

In the current paper, a biomechanical model of human body with unique structure is developed for evaluating the biodynamic responses, the vibration transmissibility and the transmitted accelerations to vertical vibration for the seated position with ignoring backrest support. In this regard, the 6-DoF Lumped-parameter model with six concentrated masses which are connected with linear springs and dampers is presented. Further, the full vehicle model is developed in ADAMS/CAR software in order to utilize the accelerations of seat under various roads excitation for different amount of vehicle speeds. Also, the vibration transmissibility and transmitted accelerations in vertical direction are measured for the different segments of human body including: Pelvis, Abdomen and Diaphragm, Chest, Torso, Back, Head and Neck. Finally, vibration transmissibility and transmitted accelerations due to the roughness of the roads surfaces are investigated for the different segments of human body in frequency domain from 0 to 50 Hz. As it is illustrated the maximum values for transmissibility for different body segments occurred for frequencies equivalent 20 to 30 Hz, it can be concluded that the human body is more sensitive to vibration with frequencies under 30 Hz.

A Real Time Traffic Sign Detection and Recognition Algorithm based on Super Fuzzy Set

A. Khodayari

Advanced Driver Assistance Systems (ADAS) benefit from current infrastructure to discern environmental information. Traffic signs are global guidelines which inform drivers from near characteristics of paths ahead. Traffic Sign Recognition (TSR) system is an ADAS that recognize traffic signs in images captured from road and show information as an adviser or transmit them to other ADASs. In this paper presents a novel machine vision algorithm for traffic sign recognition based on fuzzy sets. This algorithm is a pipeline consists of multiple fuzzy set that create a fuzzy space here called Super Fuzzy Set (SFS). SFS helped to design a flexible and fast algorithm for recognizing traffic signs in a real-time application. Designed algorithm was implemented in computer-based system and checked on a test car in real urban environment. 83.34% accuracy rate was obtained in real-time test.

Cost and Effectiveness Study of Hybrid Electric Vehicle Technologies Based on China Data

z. Liu