ARAI Journal of Mobility Technology

Killing from Both Ends: A Re-Definition of Road Traffic Mortality

Ritu Vasu Primlani — 2023-02-01

The metric of Road Traffic Mortality (RTM) is important: it is indicative of road safety, and is used to inform policy. Hitherto RTM is considered to be caused through collision or impact, or the “front” end of the vehicle. Mortality and morbidity arising from the “back” end of the vehicle, i.e., through tailpipe emissions, tends not to be included in the definition, or in the metric of RTM. Additionally, despite its widespread usage globally, RTM seems to lack a universal or standard definition. RTM is currently used interchangeably with about ten other acronyms. This lack of standard definition along with the exclusion of TRAP may underestimate the true mortality and morbidity arising from vehicular traffic. Further, the exclusion of mortality due to TRAP from RTM may relieve public policy from addressing this public health and climate change issue. A standardized definition of RTM is proposed in this paper. We are recommending the inclusion of exposure-related mortality and morbidity into RTM. To that end, the bifurcation of the definition of RTM into RTMi (Impact-related RTM) and RTMe (exposure-related RTM, such as through air or noise pollution) is proposed. This inclusion of RTMe into the metric of RTM might provide a legislative domicile for exposure-related mortality, advise policy change, and serve the dual purpose of strengthening climate policy efforts while bolstering public health.

Novel Microstructural Necessities for High Durable Automotive Speed Gears

C. Karthikeyan — 2023-02-01

In general, for automotive transmission gears, carburizing / carbonitriding process is being followed globally for its superior bending and rolling contact fatigue properties. These properties are widely influenced by various factors like material chemistry, hardness, hardening depth, microstructure and residual stress, etc. Out of these factors, microstructural requirements are vital for transmission gear’s durability which being controlled by various process methods. This research work explains, experimental research on microstructure characteristics improvement for highest durability of the gear. Higher retained austenite in the microstructure is detrimental for bending fatigue life in longer cycle regime due to drop in strength. But, it is beneficial for pitting resistance due to ability of deforming plastically. To balance both bending fatigue & pitting resistance, retained austenite level is aimed to control in surface & sub-surface of transmission gear by modifying carburizing process. Comparative study on conventional and modified carburizing process carried-out for hardness profile, phase analysis, retained austenite profile and residual stress. Durability testing on transmission gear revealed that survival life with modified carburizing cycle is more than two times of conventional process.

FE Simulation of Truck Tire Manufacturing Process

Tejal Pore — 2023-02-01

Pneumatic Tires are one of the most important components in automobiles whether in aviation, 2/3/4 wheels drive or industrial applications. The tire is a complex assembly of numerous products which are assembled on a drum and then cured in a press under heat and pressure. Michelin being one of the premium tire manufacturing company, emphasize on use of latest technology at every stage of Tire manufacturing. The complex tire manufacturing process, from design conception till final assembly is currently simulated at Michelin using inhouse CAD/FEA simulation software. Use of FEA tools in manufacturing process simulation allows engineer to iterate over different mixes and evolving designs. In current scope, pre-defined FE template is developed for Michelin to simulate physical truck tire manufacturing process to allows user to perform automated FE iterations on iterative designs, materials etc improving the result output and increasing the productivity of user. Truck tire manufacturing process from green tire to cured tire is simulated as large displacement, 2d axisymmetric FE analysis with viscous or viscoelastic materials. Results of FE simulation are compared with that of Tire architect post manufacturing to marks effectiveness of FE analysis.

Particulate Matter Separator Analysis for Compression Ignition Engines Adhering Bharat Stage VI Norms

Devendra Vashist — 2023-02-01

In compliance of the stringent Bharat Stage VI emission norms control of particulate matter in diesel engine exhaust emission is currently achieved through diesel particulate filter, catalytic convertors, baffle filters of various designs. In the present research a device comprising of a spiral duct with increasing cross sectional area over the length is designed. The duct has a lining of heat resistant and porous material fixed along the inside walls. The device is fitted at the tail pipe of compression ignition engine driven vehicle through an inlet pipe of engine exhaust with outlet connected to the tail pipe of the exhaust system. This device will collect the particulate matter in the heat resistant porous lining along the walls of the spiral thus reducing the particulate matter. The spiral flow design was simulated and was found to be in line of acceptance of flow parameters. The developed sleek design can be easily retrofitted in the existing fleet of vehicles making them compliant for stringent statuary emission norms.

Gear Shift Quality Enhancement Parameters in Light Commercial Vehicles

J. Shanmugasundaram — 2023-02-01

In the present scenario enhancements of human ergonomics in Light commercial vehicles are imperative to implement customer comfort in vehicle level. Thus the gear shift mechanism plays an important role in the interface between the driver and vehicle. An exact and smooth running gear shift feel typically depends on the combination of both internal and external shifting elements of the gearbox and Change shift operation(CSO) system. The objective of this paper is to explain the parameters that impacts the gear shift quality and how it is improved by taking multiple design iterations in Light commercial vehicle platform through both objective and subjective evaluations. These iterations are given better results on gear shift feel in dynamic as well as static condition. This lead us to facilitate better shift comfort to end users. The content of the paper is limited to the scope of gear shift quality improvements at manual transmission and change shift operation components.

Effect of Normalizing on Semi Float Axle Shaft Performance - Case Study

Yathish Rao — 2023-02-09

The primary function of axle shaft in semi float rear axle is to transmit the power to wheels. These shafts would experience the torsional load along with bending load as well. Hence shaft metallurgical structure at case & core would become very important. The objective of this study is to understand the importance of normalizing heat treatment process carried out at post forging treatment. Bench test Performance study conducted by comparing the normalized shaft Vs nonnormalized shaft. Ultimate torsion test, torsional impact test & shaft side impact test conducted on both the shafts. The ultimate torsion test result shows JAEL of normalized shaft is 5106Nm & non normalized shaft is 4718Nm. The drop is 7.6%. The torsional impact test shows peak torque of normalizing shaft is 9384Nm & non normalizing shaft is 8386Nm. The drop is 10.6%. The side impact test shows impact energy of normalized shaft is 2903 Jouls & non normalized shaft is 2321Joule. The drop is 20%. The fractography shows ductile fracture in normalized shafts & nonnormalized shaft shows brittle. This is evident by complete fracture (breakage) in non- normalized shaft & bend in (not broken) normalized shaft. Micro structural comparison shows the grain size in normalized shaft is finer but non- normalized shafts are coarser. During the impact test, the fracture occurs by sudden heavy load applied on part surface, causes the tremendous shock load in the shaft. As a result microcracks generates at multiple points & propagates through the grain boundary. This phenomenon reduces fracture toughness characteristics & hastens the dislocation movements. Normalized shaft having finer grain size, shows sufficient ductility before final fracture but non normalized shaft do shows brittle nature due to coarser grain size. Relatively non normalized shaft shows lesser ability to absorb impact energy, JAEL torque & peak torque. The coarser grain size is easing the fracture in non- normalized shaft.

Mathematical Model and Simulation for Improving Brake, Bump and Roll Steers in Light Commercial Vehicle (LCV)

Mahadevan Pichandi — 2023-02-09

Due to recent infrastructural developments and emerging competitive automotive market in India, there is seen a huge shift in customer demand and vehicle drivability pattern for small commercial vehicles. Various factors contributing to driver’s fatigue include driver negligence, inappropriate driving habits and vehicle inherent design error due to which a driver is forced to make frequent steering wheel corrections so as to make the vehicle run in a straight line. Thus, optimization of steering, suspension and front axle geometry becomes important for improving the overall vehicle drivability and reducing the driver fatigue. Mentioned herewith are the major kinematic characteristics in a vehicle which plays vital role for ensuring vehicle improved drivability – Brake steer, Bump steer, Roll steer and Ackerman Geometry. As on today, the above analysis for deriving optimized linkages hard points for steering, suspension and front axle system are done in customized Multi body dynamics software’s like ADAMS/Trucksim. Although the derived hard points in such MBD software’s are precise yet there are several drawbacks in such approach like increase in overall project time plan, mainly due to the vehicle packaging issues for the proposed hard points and also these software customized license and AMC are quite high which increases the overall operating cost of a project. In this paper, an approach has been developed so as to derive these linkages hard points through mathematical calculation and kinematic simulation model in product design Catia platform itself. This helps the designer to derive the optimized hard points of linkages for “n” number of design iterations at the concept stage itself. Thus, this design methodology saves not only on the project design cost but also it reduces the overall product design lifecycle and gives the respective designer to choose the optimum hard point based upon the vehicle packaging feasibility Brake steer, Bump steer, Roll steer, Catia 2D layout, Camber, TCD, Ackermann error.

Investigation and Study of Ammonium Hydroxide and Biodiesel Blend as an IC Engine Fuel

Bokam Surya Sashikanth — 2023-02-09

The use of conventional fossil fuel has resulted in global warming. Biodiesel is a substitute fuel obtained from vegetable oil by transesterification process which can replace conventional diesel. Good alternative to traditional hydrocarbon-based fuel is ammonia combined with a biofuel. Ammonia is free of Carbon and can be extracted from sustainable renewable energy sources. It can be used with slight modifications on current IC engines. However running the engine on pure ammonia poses a lot of challenges which needs to be tackled. Running the engine on Biodiesel results in slightly more NOx emission, compared with traditional fuel. In the present study an experimentation has been carried out to examine the effect of biodiesel and ammonium hydroxide blend on ICE performance, emission and combustion aspects, in terms of specific fuel consumption, brake thermal efficiency, Nitrogen oxides (NOx) and Hydrocarbon (HC), Carbon monoxide (CO) and Carbon dioxide emissions. Biodiesel blends are examined using a single cylinder four stroke Kirloskar ICE. Experiments have been performed with varying percentages of ammonium hydroxide (3%, 6%, 9%) and B50 (50% diesel and 50% Karanja biodiesel) blended with Diesel and then compared with base line conventional diesel. This paper will help in understanding how percentage variation in ammonium hydroxide and biodiesel blend will effect emission and performance.

Effects of Fuel and Diesel Particulate Filter on Exhaust Gases Emissions using Ricardo WAVE

Santhosh V Kumar — 2023-02-09

Up to one-third of the light mobility vehicles and a considerable amount of heavy mobility vehicles such as trucks utilize engines powered by diesel fuel. Historically and presently, diesel fuel emits more pollutants on combustion than its counterpart, petrol, hence the new emission norms introduced by the governing body hopes to reduce the pollutants generated by these vehicles. The most notable addition to the newly adopted BS6 emissions norms is the addition of a Diesel Particulate Filter to the exhaust system of diesel engine vehicles which aims to cut down on harmful emissions such as NOx, CO and unburnt HC. An unconventional method to reduce emissions is to use biofuel and biodiesel as an alternative to conventional diesel to reduce harmful emissions. This present work will analyse and compare the effect of a DPF and biofuel on exhaust gas emissions. The Kirloskar TV-1 engine model was used for the analysis was produced on Ricardo WAVE and the engine model was validated with experimentally measured data for the same engine in [13]. The addition of a DPF reduced CO, HC and NOx emissions by an average of 10.2%, 14.8% and 63.4% respectively compared to emissions with the use of an unfiltered exhaust. The simulation results showed that an increase in biofuel concentration by 5% in the biodiesel (B5 to B20), reduced the CO by 4.2%, and increased NOx emissions by 3.2% while having identical brake thermal efficiency under ideal combustion conditions. The decrease in HC emissions was minuscule which change in biofuel concentration.

Noise and Vibration Analysis of Electric Vehicle Motor

H. V. Santhosh Kumar — 2023-02-09

NVH testing is an inseparable part of the automotive product and component design and development process. With the global shift towards hybrid and electric vehicles, it is important to understand the NVH characteristics of electric power trains. Brushless DC (BLDC) motors are the most commonly used electric vehicle motors but one of their major drawbacks is the acoustic noise and vibration caused by torque ripples. This project investigates the source of noise and vibration in an 800 W BLDC hub Motor used in an Electric Scooter. A 3D model has been generated approximately to the real life model then Modal analysis using FEM is performed using Ansys to determine the natural frequency of the vibrating parts of the motor in static conditions. The results of these simulations are to be compared and validated experimentally. The dynamic condition frequencies are also determined. It also deals experimental Noise Analysis.

Editorial

Dr. Ramesh A — 2023-02-09

The need for reducing green-house gas emissions, improving urban air quality and the drive towards the use of renewable energy are bringing about several changes in the automotive and captive power generation sectors. Significant developments have occurred at an unprecedented pace in the past decade in all spheres such as energy production, energy storage, methods of providing shaft power from available sources, alternative fuels, combining energy sources for optimal utilization and recovery of otherwise wasted energy. While there are several options available, the choice for a particular sector like automotive and within that sector like urban, highway or off-highway has to be carefully made by weighing long and short term impacts.

The automobiles of today have undergone drastic changes over the last couple of decades that have enabled ultra-low emissions to be achieved along with good fuel economy. Thanks to the development and application of advanced electronics, drive by wire systems, model based controllers and many other such innovations. Engines in particular have undergone radical changes due to advancements in materials, combustion technologies, after treatment systems, air induction systems, friction reduction, turbocharging, electrification of subsystems and controls. The role of an engine in a car is changing due to the increased employment of electrical drives. Hybrid electric propulsion is expected to play an important role during the transition to all electric drives in passenger cars. Their application in off highway and defence systems can also bring about several benefits. They can enhance the efficiency of operation of the engine and thus reduce green-house gas emissions. This will call for advanced modelling, simulation and experimentation of the combined drives. Alternative fuels that are renewable and low in carbon content are also expected to play a major role in the future. Fuel cells in combination with conventional electrical drives have high potential for enhanced performance in specific applications like hauling trucks and locomotives.

Different technologies have to compete with one another with the common goal of providing clean and sustainable motive power. Well to wheel and cradle to grave assessment of available options have to be made before large scale implementation specific to a particular sector. Bright ideas and radically new approaches that come from free exchange of information and unbiased assessment have played a key role in improving all aspects of mobility. Innovation is the key for developing and suitably implementing appropriate technologies. No idea can be left without consideration if it is technically sound, even if it does not initially show economic benefits. Many of the devices we use today emerged from seemingly complicated ideas when they were first conceived by the inventors and were the made practically viable through subsequent iterative steps. This journal helps bring together ideas and experiences on mobility from industry professionals, budding engineers and researchers. The articles will kindle the minds of young engineers to explore new avenues and also expose industry professionals to the current developments and future directions.