Jawaharlal Nehru Technological University Hyderabad B.Tech IV Year AUTOMOBILE ENGINEERING Previous Question Paper (July/August - 2022 - R16)

Internal Combustion (I.C.) engines and Hybrid engines differ fundamentally in their energy conversion and storage principles:

• Energy Source: I.C. engines rely solely on the chemical energy of fossil fuels (petrol or diesel), whereas hybrid engines combine an I.C. engine with an electric motor powered by a high-voltage battery pack.
• Construction: I.C. engines consist of a cylinder block, piston, crankshaft, and valvetrain to convert thermal energy into mechanical work. Hybrid systems incorporate additional components including an electric motor/generator, a power control unit (PCU), and a traction battery.
• Operational Principle: I.C. engines operate continuously during vehicle movement. Hybrid systems utilize a control strategy to switch between the engine and motor, or use both simultaneously, often employing regenerative braking to capture energy that is otherwise lost as heat in conventional I.C. systems.
• Transmission: I.C. engines typically use conventional manual or automatic transmissions. Hybrids often use an electronic continuously variable transmission (e-CVT) to manage the power split between the engine and the electric motor.

The automobile chassis acts as the structural backbone of the vehicle, supporting all mechanical components and the body. Its primary components include:

• Frame: The main load-bearing structure, typically made of steel or aluminum, which supports the engine, transmission, and suspension. It can be a ladder frame, backbone, or monocoque design.
• Suspension System: Includes springs, shock absorbers, and linkages that connect the wheels to the frame, absorbing road shocks and ensuring stability.
• Steering System: Comprises the steering wheel, column, and linkage mechanisms (such as rack and pinion) that allow the driver to control the direction of the vehicle.
• Powerplant/Drivetrain: Includes the engine, clutch, gearbox, propeller shaft, and axles, which generate and transmit power to the wheels.
• Braking System: Consists of master cylinders, lines, and wheel units (discs or drums) used to decelerate or stop the vehicle.
• Wheels and Tyres: The interface between the chassis and the road, providing traction and supporting the vehicle's weight.
• Electrical System: Includes the battery, alternator, wiring harness, and lighting, which power the ignition, sensors, and safety systems.