With new models of cars and SUVs doled out by manufacturers every day, engineering lead times have been reduced significantly. The budget slice for physical testing has been drastically reduced, and in some cases physical testing is just not an option. Lead times for automotive majors have been reduced from 50+ months in the 1990s to 15 months with the adoption of CAE. Physical testing which used to involve large investments and 4-6 months has been replaced by CAE simulation which can accomplish the same task in 1-2 months with much smaller investments. The NISA product line has been helping the automotive industry for the last two decades in analyzing many complex problems.

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Design analysis of heavy duty truck cab

Objective:

A Canadian logging truck manufacturer needed the cabins of its trucks designed for crushing loads from falling trees and impact from logs being carried on the trailer. The truck cabins needed to pass a beam penetration test.

Methodology:

All cabs are required to pass several different operating loads as specified by the manufacturer and governmental regulations.

Crush analysis was conducted, which simulates forward moving logs penetrating the cab from the rear panel if a fully loaded truck were to stop suddenly. In addition, depending upon the application of truck, the cab is required to withstand localized loads such as roof crush, snow load and beam penetration due to either falling trees or light/sign poles. The model consisted of shell elements for the cab. The panels were connected using rigid links for spot-weld simulation. The frame and suspension were included using beam elements.

The truck cabins were suitably reinforced and the manufacturer passed government regulations.

Airflow and thermal analysis in an automotive alternator

An automotive alternator manufacturer re-engineered an alternator which was to be fitted into a popular car. The highlight of the alternator was its fan-less design. Fins on the stator and rotor moved relatively to each other creating a natural suction for air. In order to determine if the device would cool itself suitably in all thermal conditions, computational fluid dynamics analysis was conducted to qualify the device.

Analysis of an automobile chassis for various road conditions

An automobile manufacturer was to launch a sports car for Indian road conditions. Indian roads are notorious for deep pot-holes which can cause extensive damage to suspension and chassis. The stress/vibration analysis was conducted on the chassis, and various g forces were simulated in the process.

Fatigue analysis of an automobile connecting rod and crankshaft

An automobile engine manufacturer complained of premature failure of a connecting rod and crankshaft. Stress/fatigue analysis were conducted to determine the life of the components after redesign.

Vibration analysis of an instrument panel of an automobile

A major SUV manufacturer complained of unnecessary vibration of the instrument panel, especially in the region of the entertainment center. Modal analysis was conducted to identify this vibration and miniscule design changes were made to nullify it. This SUV in full-scale production is now commended for having one of the quietest cabins.

Random vibration analysis of a bus body

A bus body manufacturer was to launch a local transport bus for Indian road conditions. Indian roads are notorious for deep pot-holes which can cause a vibration of the bus body. The random vibration analysis was conducted on the body to check structural integrity during most service conditions.

Vibration analysis of a motorcycle crank case

A motorcycle manufacturer complained of excessive vibration/ sound from the crankcase at certain throttle levels. Vibration/modal analysis was carried out and it was determined that the cause was a mass imbalance inside the crank case. A small mass in the form of a plate was fitted inside the crank case and the vibration was eliminated at all throttle levels.

Vibration analysis of a motorcycle exhaust system

A motorcycle manufacturer complained of premature failure of an important rubber washer at the flange connecting the exhaust to the engine outlet. Vibration/modal analysis was carried out and to determine that the cause was unwanted vibration of the exhaust pipe. The bracket connecting the exhaust to the main body was shifted by a small degree and the vibration was eliminated.

Structural analysis of a scooter rear wheel hub during acceleration and braking

A scooter manufacturer complained of premature failure of a wheel hub under certain road conditions. Stress and Vibration Analysis determined that it was the clamp joining the hub to the wheel rim that was the cause for failure. A new clamping mechanism was designed to re-qualify the vehicle.

Structural analysis of a shear pin assembly for a bucket excavator

A major manufacturer of heavy machinery complained of the failure of the shear-pin assembly of one of it bucket excavator models. Stress Analysis was conducted on the assembly and it was determined that the geometry of the shear pin needed change.