Ashok Leyland Technical Center

Chennai, India

Ashok Leyland Technical Center

Chennai, India
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Amanulla B.,Ashok Leyland Technical Center | Chakrabarti S.,Indian Institute of Technology Kanpur | Singh S.N.,Indian Institute of Technology Kanpur
IEEE Transactions on Power Delivery | Year: 2012

A power distribution system reconfiguration methodology considering the reliability and the power loss is developed in this paper. Probabilistic reliability models are used in order to evaluate the reliability at the load points. An algorithm for finding the minimal cut sets is utilized to find the minimal set of components appearing between the feeder and any particular load point. The optimal status of the switches in order to maximize the reliability and minimize the real power loss is found by a binary particle swarm optimization-based search algorithm. The effectiveness of the proposed methodology is demonstrated on a 33-bus and a 123-bus radial distribution system. © 2012 IEEE.


Vadiraj A.,Ashok Leyland Technical Center | Balachandran G.,Kalyani Carpenter Special Steels Ltd. | Kamaraj M.,Indian Institute of Technology Madras | Kazuya E.,Nagaoka University of Technology
Materials and Design | Year: 2011

The effect of tempering temperature (100-600 °C) on the hardness and wear resistance of a series of quenched and tempered hypereutectic alloyed gray cast irons has been studied in this work. Hardness was observed decreases with increase in tempering temperature and this trend is influenced by alloying additions and the volume of graphite flakes. Hardness of alloyed gray irons is also influenced by solid solution strengthening of tempered ferrite and carbide content and their distribution. The wear loss of alloyed cast irons was found to be lowest at a tempering temperature of 100 °C and 400 °C. The optimum tempering temperature is 400 °C with moderate hardness and low wear rate. This has been attributed to strengthening of the matrix at this temperature. Beyond 400 °C, the wear rate increases significantly due to carbide coagulation. © 2010 Elsevier Ltd.


Balachandran G.,Kalyani Carpenter Special Steels Ltd. | Vadiraj A.,Ashok Leyland Technical Center | Kamaraj M.,Indian Institute of Technology Madras | Kazuya E.,Nagaoka University of Technology
Materials and Design | Year: 2011

Three groups of hypereutectic cast irons alloyed with Cu, Ni and microalloying additive like Ti and Nb were examined for its hardness and wear resistance in the austempered (360 °C/3. h) and quenched and tempered conditions at varying tempering temperatures. It is observed that the cast irons in the quenched and tempered condition showed good wear resistance and moderate hardness at 400 °C. This was comparable with the wear resistance in austempered condition. The study also showed that in quenched and tempered condition, increasing Cu content in cast irons improved its wear resistance moderately while increasing Ni content has decreased its wear resistance. The presence of strong carbide formers (Nb, Ti) did not give significant improvement in wear resistance in quenched and tempered condition. Even in austempered alloys, higher Cu content increases its wear resistance and higher Ni content decreases their wear resistance. The austempered alloys showed ausferritic microstructure with 20% austenite phase which enhances wear resistance through transformation induced plasticity effect. On the other hand, the quenched and tempered alloys showed good wear resistance at 400. °C due to fine tempered carbides in the matrix. © 2011 Elsevier Ltd.


Balasubramanian B.,Ashok Leyland Technical Center
2015 IEEE International Transportation Electrification Conference, ITEC-India 2015 | Year: 2015

This paper describes the indigenous development of CAN based low-cost cluster controller which drives the non-CAN cluster in a CAN based vehicle. The use of CAN network in vehicle is ever growing and has number of advantages which includes efficient diagnostics, low-cost and reduced wiring harness. The use of CAN network in a module expects the other interconnected modules also to be CAN based. Typical example being development of EV or HEV requires the instrument cluster of the vehicle also to be CAN based, as its information mostly available in CAN (For example SOC of High voltage battery). The indigenously developed controller drives the non-CAN cluster dials based on the CAN message from vehicle control unit. The controller hardware is designed to be universal driver which can drive almost all instrument clusters. This controller also has reverse functionality that converts the physical signal from vehicle to CAN message. The advantages being low development and implementation cost, compatibility to all clusters with minor software changes, retainment of the existing cluster, cabin trims and avoids need for new cluster development which involves huge development cost. © 2015 IEEE.


Balasubramanian B.,Ashok Leyland Technical Center
2015 IEEE International Transportation Electrification Conference, ITEC-India 2015 | Year: 2015

This paper describes the implementation of sensor-less hill-assist control system in electric Light Commercial Vehicle (LCV). In manual transmission vehicles without hill-assist, the restart at the slope can be done through skilled clutch control. For the vehicles not having clutch (auto transmission or fixed gear electric vehicles), the restart of the vehicle at hill is not possible with driver skills alone and needs the hill-assist functionality. It involves the costlier sensors and control mechanism for its implementation [1, 2]. The work aimed at implementing hill-assist functionality without the use of gradient sensor and brake actuators. In the absence of brake actuators the holding torque is provided by the traction motor. The PID controller with parameterized vehicle model in loop calculates the holding torque required. The precise vehicle model for the controller built through vehicle tests. As the PID gains are sensitive to the hill slope and vehicle load, they are indirectly estimated through controlled rollback and precise model of the vehicle implemented in vehicle controller. The estimation slope helps to change the PID parameters online to reduce the speed error as quickly as possible. The modeling, simulation of the hill-assist algorithm is presented. The algorithm is embedded with the existing traction control module of the electric LCV. Test results of the hill-assist operation are presented on comparison with the simulation results. © 2015 IEEE.


Vadiraj A.,Ashok Leyland Technical Center | Kamaraj M.,Indian Institute of Technology Madras | Sreenivasan V.S.,Ashok Leyland Technical Center
Tribology International | Year: 2011

Friction and wear behavior of MoS2, boric acid, graphite and TiO2 has been compared under extreme boundary lubrication condition. Boundary lubrication was simulated for the study. Results show that MoS 2 and graphite were 3050% more effective than other two lubricants. Friction coefficient shows a decreasing trend with increase in sliding speed due to increasing temperature and higher shear force. High friction coefficient values were recorded for all the lubricants (0.20.5). This is due to predominating solid interactions during boundary lubrication condition. Boric acid and TiO2 were not much effective in lubrication. © 2011 Elsevier Ltd. All rights reserved.


Chatterjee S.,Ashok Leyland Technical Center | Sivasubrahmaniyan A.,Ashok Leyland Technical Center
SAE Technical Papers | Year: 2013

Misfires in SI engines are one of the major causes for increase in vehicle exhaust emissions beyond the regulatory limit. Misfires have a great potential to destroy catalytic converters due to increased exhaust temperatures caused by unburned fuel from the misfired cylinders. It also leads to decrease in engine efficiency and high fuel consumption. Misfires are majorly caused due to unfavorable spark plug temperatures, low ignition energy, fuel system malfunction, improper air-fuel mixture ratio, flame propagation speed, etc. Monitoring of misfire detection in SI engines is an essential requirement of On-Board Diagnostic (OBD) regulations in many countries. This paper compares the conventional and advanced misfire detection technologies in spark-ignition engines, available and under development for meeting the OBD regulations worldwide. It describes the misfire detection principle. Comparison of the methods is done considering system cost, system accuracy in detecting misfire, ease of implementation and conclusions are drawn. © 2013 SAE International.


Chatterjee S.,Ashok Leyland Technical Center
SAE Technical Papers | Year: 2013

In the recent years, due to rising fuel costs, transportation technologies that provide better fuel economy than conventional vehicle are gaining in popularity with masses. Also, tighter emission norms by various governments have prompted OEMs to look at alternate solutions such as hybrid vehicles. Hybrid vehicles employ an internal combustion engine as well as an alternate energy source to power road vehicles. Various types of hybrid vehicles are available such as mild hybrid, full hybrid, series, parallel and series-parallel hybrids. The level of hybridization (mild or full) and the different powertrain combination (series or parallel) result that on the same route, the engine in a hybrid vehicle operates very different to that of conventional vehicle. The fuel consumed and emissions are also significantly lower in hybrid vehicle. To certify hybrid vehicles, regulators in many countries have modified existing procedures applicable to conventional vehicles. This paper gives an overview about the types of hybrid Powertrain combination. Indian procedure for certification of Heavy Duty Hybrid vehicles is explained. Other methods for emission testing being used worldwide are also presented here. © 2013 SAE International.


Harinarayanan H.,Ashok Leyland Technical Center
SAE Technical Papers | Year: 2013

Commercial vehicle payload depends on the client for which the vehicle fleet owner is operating. Load carriers like flatbed trailer offer the flexibility to be loaded with a large number of light payloads or a few numbers of massive payloads. Such load carriers have to be evaluated for various possibilities of loading patterns that could happen in the market. The objective of this work is to evaluate flatbed trailer for its structural strength for different customer application cases, using computer simulation. Structural load cases due to payloads like containers, steel coils and cement bags are arrived at. Static structural analysis using MSC Nastran is performed to evaluate for the worst customer loading pattern from structural stress point of view. This paper also describes a simplified method for simulating the effect of trailer suspension, tractor suspension and the fifth-wheel coupling in the analysis whose detailed modeling is not possible at the concept level. This approach helps to find the possible critical locations and to select the best design out of several design proposals at the concept stage itself. The paper is the authoritative source for the abstract. Copyright © 2013 SAE International.


Kshirsagar C.,Ashok Leyland Technical Center
SAE Technical Papers | Year: 2015

Engines of commercial vehicles deliver significant amount of power (more than 25% of propulsive power) for non-propulsive loads such as air-conditioner, alternator, air compressor, radiator fan, steering oil pump, lights etc. Use of these auxiliaries cause sub-optimal utilization of engine power resulting in increased fuel consumption and emissions. A fuel cell powered auxiliary power unit (FC-APU) is proposed to isolate the auxiliaries from the engine. Use of FC-APU shall help improve load carrying capacity, gradeability, fuel efficiency and emissions of the vehicle. This paper describes a mathematical system level model developed using MATLAB-SIMULINK to estimate auxiliary power consumption and simulate FC-APU system. A statistical analysis is performed on the power consumed by various auxiliaries during different duty cycles. The data is used to propose a FC- APU system. Fuel cell is the most expensive component in the system. Cost of the fuel cell increases with increase in power rating. Hence, objective of the system simulation is to propose a FC-APU system featuring fuel cell with lowest possible power rating. Copyright © 2015 SAE International and Copyright © SAEINDIA.

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