Showing 7 results for Hosseini
P. Hosseini-Tehrani, S. Pirmohammad,
Volume 1, Issue 4 (12-2011)
Abstract
S. Javan, S. V. Hosseini, S. Sh. Alaviyoun,
Volume 2, Issue 1 (1-2012)
Abstract
Temperature is one of the effective parameters in erosion of spark plug electrodes. In this research, temperature of
spark plug was measured in engine's different operation conditions with two types of fuels: compressed natural gas and
gasoline. Test results showed that, temperature of center electrode is lower than ground electrode and maximum
difference between them is 110ºC that occurs at 2500 rpm and full load conditions. Maximum temperature of spark
plug occurs with CNG under full load conditions and 6380 rpm. In these conditions, ground electrode’s temperature
reaches to 960ºC which is very prone to pre-ignition. On the other hand, center electrode’s temperature is 195ºC higher
than the same condition with gasoline as a fuel which cause more electrode erosion rate. This temperature rise lead to
cold type spark plug selection because of its better heat transfer. Spark plug erosion was studied after endurance tests
with CNG as a fuel. Electrodes have non uniform wear patterns and consequently gap growth is not uniform. The
average gap growth for two sets of spark plugs after two similar 200 hr endurance tests is 49.6%
P. Hosseini Tehrani, M. Talebi,
Volume 2, Issue 3 (7-2012)
Abstract
In this paper, finite element elastic contact analysis of a functionally graded (FG) hollow brake disk in
contact with pad, subjected to rotation, contact pressure and frictional heat is presented. The material
properties vary through the thickness according to a power-law characterised by a grading index, n. The
material property is purely steel at the core part and gradually moves and approaches to the ceramic
properties at the surfaces of the FGM disk. In this task, thermal analyses are performed on two ventilated
disk brake one of them is constructed of functionally graded composite material and the other is a
homogeny disk brake which is constructed of steel alloy. In this study three-dimensional finite element
model and ABAQUS software is used. Through comparison of temperature and displacement fields the
benefits of using functionally graded material is investigated. It is shown that temperature variation in
FGM disk is much lower than steel disks, it may be concluded that FGMs disk restrain the growth of
thermal perturbation and delay the contact separation..
R. Hosseini, M. Azadi, , , ,
Volume 5, Issue 4 (12-2015)
Abstract
In the present paper, the modal analysis on a full finite element model of an off-road vehicle. This vehicle was modeled in the CATIA software and then meshed in the HYPERMESH software. The free vibration analysis was conducted by the ABAQUS software. By applying an external displacement, the forced vibration analysis was also performed. As a result, natural frequencies and shape modes were extracted to detect critical regions. Then, some improvements were suggested to have better vibration behavior of the vehicle.
S.s. Hosseini, J. Marzbanrad,
Volume 7, Issue 4 (12-2017)
Abstract
Car design incorporates many engineering sciences where today, have led to the use of advanced technologies in automobiles to provide more satisfaction and comfort for the passengers, increase the quality of vehicles, efficiency and more pleasure than previous cars. These issues can be categorized into two groups in general. In the first group, the effects and performance of components involved in vehicle vibrations are considered, and in the second group, attention is paid to the importance of joints and junctions of these components. Heretofore, in order to minimize vehicle NVH (noise, vibration and harshness), an exuberance of efforts have been done to raise the passengers comfort. In the meantime, it should be noted that the engine mounts play a considerable and serious role in reducing vibration exchanged between the engine and chassis. In designing the engine mounts, the most important concern is to balance the two opposite criteria that come into the car as a result of different vibration inputs (road and motor). Generally, vehicle engine mounts are used by three types of targets (motor bearing weight, motor vibration absorption, motor overloading, acceleration or braking). With the development of the automotive industry, the tendency towards the use of more efficient engine mount categories, has been prepared.
This article describes a concise functional overview of the engine mount in automobiles; it illustrates operating frequency range, relationship of the P and boundary diagram of engine mounts with other car collections, torque roll axis, positioning public types of the car’s engine mounts; and it also compares their operations. Afterwards, the structure and the basic functional of hydraulic engine mount are described as the most common engine mount categories. Finally, advantages and disadvantages of various types engine mounts with capability of use in the vehicle (including elastomeric, hydraulic (with inertia track or/and decouplier or/and bell plate (plunger), semi-active (switchable) and active hydraulic engine mount) are compared with each other.
Mr Meghdad Pishgooie, Seyed Masoud Hosseini Sarvari, Seyed Hossein Mansouri,
Volume 9, Issue 1 (3-2019)
Abstract
The purpose of this study is to investigate the effect of radiation heat transfer on temperature distribution and heat flux to the walls of a diesel engine. A diffusion flame is modeled in a simple cylindrical geometry and boundary conditions are defined. A specific solver which can model the turbulent diffusion flame by considering radiation in participating media is used to solve the problem. The solver is verified using experimental data of a furnace. The results show that with considering radiation and non-gray effects in the model, the flame temperature is calculated higher than that with ignoring these effects (about 11% in problem considered in this study).
Ashkan Moosavian, Alireza Hosseini, Seyed Mohammad Jafari, Iman Chitsaz, Shahriar Baradaran Shokouhi,
Volume 12, Issue 2 (6-2022)
Abstract
In this paper, to address the problem of using displacement sensors in measuring the transverse vibration of engine accessory belt, a novel non-contact method based on machine vision and Mask-RCNN model is proposed. Mask-RCNN model was trained using the videos captured by a high speed camera. The results showed that RCNN model had an accuracy of 93% in detection of the accessory belt during the test. Afterward, the belt curve was obtained by a polynomial regression to obtain its performance parameters. The results showed that normal vibration of the center of the belt was in the range of 2 to 3 mm, but the maximum vibration was 8.7 mm and happened in the engine speed of 4200 rpm. Also, vibration frequency of the belt was obtained 124 Hz. Moreover, the minimum belt oscillation occurred at the beginning point of the belt on the TVD pulley, whereas the maximum oscillation occurred at a point close to the center of the belt at a distance of 16 mm from it. The results show that the proposed method can effectively be used for determination of the transvers vibration of the engine accessory belts, because despite the precise measurement of the belt vibration at any point, can provide the instantaneous position curve of all belt points and the equation of the belt curve at any moment. Useful information such as the belt point having the maximum vibration, belt slope, vibration frequency and scatter band of the belt vibration can be obtained as well.
