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In view of the stringent emission norms laid out by government of India, BSVI Engines are with additional heat rejection requirements with limited packaging space for Cooling system. An appropriate Radiator, Charge Air Cooler and Fan is decided within the available packaging space based on the Engine heat rejection needs. In this paper an approach is defined to arrive at a Cooling system architecture which is very compact in design and packaged between the Engine and Front member in a limited space. Modelling is done in Thermal simulation software KULI. Good correlation is achieved between simulation to test results.

In today’s world, due to fast depletion of fossil fuel and the increasing CO2 emission, the need to switch to alternate energy sources are higher. Stringent norms on exhaust emissions in IC Engine vehicles implies, very complex after treatment systems. Already many OEMs have refined their development strategies towards phasing out of IC Engines and bringing in Fuel Cell vehicles, Battery Electric Vehicles and Hydrogen IC Engine vehicles. Focus is on Hydrogen for Long Haul vehicles. In this paper cooling system design is demonstrated for Fuel Cell, Battery and Power Electronics system in a Heavy Duty Fuel Cell Electric Truck. Radiator and Fans are selected based on the overall heat rejection and Coolant inlet temperature requirements of components. Cooling system circuit and pump is decided to meet the coolant flow rate targets. High temperature cooling system and Low temperature cooling system are explained in detail. Thermal simulation is done using simulation software KULI.

Diesel engine pollutants include Oxides of Nitrogen (NOx) and Particulate Matter (PM) which are traditionally known for their trade-off characteristics. It’s been a challenge to reduce both pollutants at the source simultaneously, except by efforts through low temperature combustion concepts. NOx formation is dependent on the combustion temperature and thus the in-cylinder reduction of NOx formation remains of utmost importance. In this regard, water injection into the intake of a heavy-duty diesel engine to reduce peak combustion temperature and thereby reducing NOx is found to be a promising technology. Current work involves the use of 1-D thermodynamic simulation using AVL BOOST for modeling the engine performance with water injection. Mixing Controlled Combustion (MCC) model was used which can model the emissions. Initially, the model validation without the water injector was carried out with experimental data.

The commercial vehicle industry is evolving faster with the rise in multifarious aspects deciding a company's progress. In the current scenario, vehicle performance and its reliability in the areas of payload, fuel economy, etc. play vital roles in determining its sustenance in the industry, in addition to reducing driver fatigue and improving comfort levels. Test quality and time is the key to assure and affirm, smooth and quick launch of the product into the market. This paper details on the design of Multi-Axis road data simulator which entails realistic loads onto the components for capturing meaningful information on behavior of the product and recreate the field failure modes. The design was conceptualized keeping in mind both cost (for initial installation and running cost) and time for testing without loss in the convergence factor.

This paper describes the system architecture together with control and diagnostics features of an indigenously developed electric vehicle controller for Light Commercial Vehicle. The key functions of vehicle controller include power management, driveline controls, regeneration and vehicle mode controls. In particular this paper presents vehicle's operational strategy in economy, normal and performance modes based on the vehicle speed and SOC. It also has feature to enable vehicle operation in reduced performance mode at low battery voltages. The battery fault predictor algorithm is also described in detail that is used to control discharge current to prevent sudden dip in SOC and to increase battery life. The vehicle control strategy is modeled & simulated using MATLAB™ environment and results for a specific test case are validated with embedded controllers-in-the-loop in a test-bench environment.

This paper describes a methodology for design and development of On-Board Diagnostic system (OBD) with an objective to improve current reliability process in order to ensure design & quality of the new system as per requirement of commercial vehicle technology. OBD is a system that detects failures which adversely affect emissions and illuminates a MIL (Malfunction Indicator Lamp) to inform the driver of a fault which may lead to increase in emissions. OBD provides standard and unrestricted access for diagnosis and repair. Below given Figure 1 shows the working principle of OBD system. The exhaust emission of a vehicle will be controlled primarily by Engine Control Unit (ECU) and Exhaust Gas After Treatment Control (EGAS CU). These two control units determine the combined operating strategies of the engine and after treatment device. Figure 1 Modern Control Architecture for OBD System in Commercial vehicle [1]

Vehicle light-weighting of late has gained a lot of importance across the automotive industry. With the developed nations like the U.S. setting stringent fuel economy targets of 54.5 mpg by 2025, the car industry's R&D is taking light weighting to a whole new level, besides improving engine efficiency. The commercial vehicles on the other hand are also gradually catching up when it comes to using alternate material for weight reduction. This paper will discuss light-weighting in the context of buses though. For a typical bus, the contribution of shell structure weight in the bus body weight is more than 40%. This qualifies as the area with a huge potential for weight saving. On the other hand the shell structure forms the base skeleton of the bus body providing it with adequate strength and stiffness for meeting both functional (bending & torsional stiffness) and passive safety requirements (rollover compliance).

In mining tippers, rear suspension plays a major role in defining vehicles ride and handling characteristics, stability and load carrying capacity. Bogie type of suspension is well suited for these applications. Bogie suspension mainly consists of bogie bracket, leaf springs and radius rods. Nonlinear static analysis is performed for a bogie bracket assembly considering bolt pretension and contacts to evaluate the static strength of bogie bracket. Since bogie bracket is connected to frame with several bolts, a sensitivity analysis is carried out to study the effect of bolt loosing on bogie bracket. The surface contact interaction (stick-slip) behavior between frame and bogie suspension mounting bracket is also studied. Good correlation is achieved with testing results.

Automotive industry is progressively embracing newer technology for buses, as they are increasingly becoming the backbone of urban transportation. Buses are generally classified based on floor heights, lengths, seating capacity and applications besides lot of other parameters. Generally low floor / low entry buses are used for city transportation, while high floor / high deck buses are used for inter urban and intercity transportation. Yet in a few developing and underdeveloped geographies across the globe, high deck or the semi low floor buses are still used for city/urban transportation. There could be a lot of reasons like infrastructure limitations, the cost of ownership or in some cases even the topology of these geographies could be unfriendly towards low floor buses and low ground clearances. Varying customer requirements, applications and environmental factors necessitates a broad range of offerings from any bus OEM.

Natural gas (CNG) vehicles have been introduced in many parts of world including India, Europe and United States and achieved tremendous success in addressing the energy security and pollution challenges. This paper describes in detail the safety requirements for CNG vehicles in India, Europe and United States. Various safety and design requirements for CNG fuel system components such as gas cylinders, cylinder valves, fuel lines, filling connection, pressure regulator, gas-air mixer, electrical systems, are explained. The safety requirements described in ISO standards, UN-ECE standards, USA FMVSS, NFPA standards and Indian Standards are compared and discussed in detail. It also specifies the procedure for commissioning and installation of CNG vehicles. Further, it is concluded that all these international standards for CNG vehicles have adequate provisions with regard to impact protection, passenger safety and fire safety.

Oil strainer is used in engine oil sump, which prevents dirt, scale and other particle from clogging downstream orifice. In this paper, dynamic analysis was carried out using FEA tool. As a part of dynamic analysis, constrained modal analysis and frequency response (steady state dynamics) analysis was done. Frequency response analysis was done for different engine exciting frequency at different service load (vibration amplitude). Modal superposition method is used for doing frequency response analysis and load is applied as base excitation. The natural frequency from modal analysis and stress response from frequency response analysis is well correlated with test results. Based on achieved good correlation with test, several design modification could be carried out in CAE before finalizing the final design.

There have always been different approaches when it comes to ‘Bus body architecture’. The design approach has gone through different phases namely, chassis based, semi integral, integral and monocoque. Equally varied is the choice of material for bus super structure. The predominantly used ones are - mild steel with galvanization, stainless steel (SS) and aluminum. This paper discusses the rationale behind choosing stainless steel for the complete bus structure. With rapid development in infrastructure and public mass transit system, it has become imperative to have a robust structure for buses that is durable and crash worthy. Among the family of stainless steels, ferritic stainless steel exhibits excellent mechanical properties with corrosion resistance and better strength to weight ratio compared to the galvanized mild steel.