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In commercial vehicles which generally have large capacity fuel tank, sloshing of fuel and its effect on the tank structure is very important aspect during fuel tank design. Dynamic pressures exerted by the fuel on baffles, end plates and tank shell during sloshing can lead to structural failures and fuel leakage problems. Fluid structure interaction simulation of automotive fuel tank sloshing and its correlation with physical test is demonstrated in this study. During physical sloshing test of 350 L fuel tank, cracks were observed on center baffle and spot weld failures developed on fuel tank shell. Same sloshing test was simulated for one sloshing cycle using fluid structure interaction approach in LS Dyna explicit FE solver. Water was used instead of fuel. Mesh free Smoothed Particle Hydrodynamics (SPH) method is used to represent water as it requires less computational time as compared to Eulerian or ALE method.

Brake steer is an undesirable phenomenon where a vehicle deviates to one side of the road during braking. Vehicle deviation i.e. drift causes driver discomfort, where a driver has to constantly apply Steering Wheel corrections while braking in order to safely maintain the desired path. In a particular model of commercial vehicle segment, an issue of unacceptable right-side vehicle drift during braking was observed which was making the drive of the vehicle unsafe for the driver. Aim of this paper is to analyse the probable causes of such a vehicle drift, to objectively measure actual vehicle drift during braking using a unique methodology. In this paper, the root cause of the brake steer is discussed and an improvement on the vehicle is proposed by changing kinematic hard points of suspension and steering linkage to reduce the brake steer to the limit that vehicle drift is almost eliminated, and vehicle becomes completely safe for the driver to drive.

During design and development of a cabin for any commercial vehicle, meeting the strength requirements of front impact as per Indian regulation (AIS-029) is a very critical milestone. AIS-029 regulation consists of three destructive tests, i.e. Front Impact Test (Test A), Roof Strength (Test B) and Rear Wall Strength (Test C). Study of energy absorbing front cabin mount, its stiffness balance with chassis and CAE correlation with physical test is demonstrated in this study. [1]

Door slam test is one of the important durability tests in door design and development. Door requires to meet certain performance requirements like it should close properly (no metal to metal contact), there should not be any leakage, and closing operation should be smooth & with minimal effort and it should survive the life of the vehicle. Virtual simulation of door slam test, correlation with physical test results and effect of various parameters like seals stiffness are demonstrated in this study. Slam Analysis was carried out in LS-Dyna solver before physical test. This not only helped in avoiding initial structural design flaws, but also helped us in deciding door latch position, effect of mass distribution in the door and study of force distribution between primary seal, secondary seal and door latch. Primary and secondary seals played a critical role in the analysis. An intended length of both the seals was tested first to get its stiffness curve.

Lot of CAE (Computer Aided Engineering) based evaluation methods and DVPs (Design Verification Process) are available which are derived from acceleration data, strain data acquired on vehicle over proving ground. Using peak load summary from acceleration inputs generic gravity loads get derived. Use of these loads for CAE analysis are having certain advantages like faster concept level evaluation, broader perspective and confidence on concept design. But there are few limitations of using these methods like it gives only broader perspective of concept design and not able to capture many failure modes and locations as per RWUP (Real World Usage Pattern). This paper explains the advantages of using WFT (Wheel Force Transducer) data for getting more reliable, realistic and co-relating more failure modes on the vehicle. WFT data acquired on all four wheel-ends at wheel center. Each wheel end transducer records 3 translational and 3 rotational forces.