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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.

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.

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).

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.

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.

Engine mounts and mounting brackets play a critical role in determining NVH performance of a vehicle. A lot of work has been done in the area of virtual simulation using FE models to study engine mounting system performance and its impact on vehicle level performance. An overall approach towards engine mounting system validation at vehicle level is also very critical to validate simulation results in a prototype based on which further refinement work will be carried. In this paper a detailed procedure for engine mount and mounting bracket physical validation at vehicle level is presented. Various tests to be performed at vehicle level to quantify engine mount and mounting bracket performance parameters is discussed in detail along with measurement procedures and techniques. Test results are interpreted and its impact on overall performance is also explained. These test results will help design engineers to further improve engineering parameters of mounts and mounting brackets.