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Underrun Protection devices (UPDs) are specially designed barriers fitted to the front, side, or rear of heavy trucks. In case of accidents, these devices prevent small vehicles such as bikes and passenger cars going underneath and thus minimizing the severity of such accident. Design and strength of UPD is such that it absorbs the impact energy and offers impact resistance to avoid the vehicle under run. Compliance to UPD safety regulations provides stringent requirements in terms of device design, dimensions, and its behavior under impact loading. Since accuracy of Computer Aided Engineering (CAE) predictions have improved, numerical tools like Finite element method (FEM) are extensively used for design, development, optimization, and performance verification with respect to target regulatory performance requirements. For improved accuracy of performance prediction through FEA, correct FE representation of sub-systems is very important.

Engine cooling systems for vehicles are used for cooling the engine fluids. The cooling system normally consists of following components: radiator, expansion tank, cooling fan, fan drive and shroud. The mounting structure for this system must be designed to withstand the loads that will be imposed by the vehicle operation which consists of stresses such as those caused by linear static and dynamic loading. Automotive industries perform various tests on vehicles in the end-user environment to reduce failures; these investigations are carried out on the design using finite element method (FEM). Finite element methods are being used routinely to analyze for structural behavior. Modeling is done with CATIA software, meshing is carried out with HYPERMESH software and solution is acquired using NASTRAN solver.

Passenger cars in the top segment have seen fast growth over the last few decades with an increasing focus on luxury, convenience, safety and the quality of driver experience. The headliner is a decorative and functional trim system covering the underside of the roof panel. It enhances the aesthetics and elegance of the car interiors. In premium vehicles, the headliner system has to suffice interior quietness and integrity apart from the performance and regulatory requirements. The Design Validation Plan requirements cover its contribution to the vehicle interior noise control, occupant safety, and perception of build quality. Contributions can be very significant and primarily be determined by design and material parameters. Also, headliner interactions with an adjacent body in white structure are crucial from performance point of view. Various foam options are available with different functions such as structural, acoustic, and energy-absorption.

Conventionally, the automotive outer panels, giving vehicle its shape, have been manufactured from steel sheets. The outer panels are subjected to loads due to wind loading, palm-prints, person leaning on the vehicle, cart hits, and hail stones for example. Consumer awareness about these two panel characteristics: Oilcanning and Dent resistance is increased, which has been observed in recent marketing studies. Apart from perceptive quality, another factor depending on the dent performance is insurance and respective cost implications. Dents can occur due to several reasons such as object hits, parking misjudgement, hail stones etc. Phenomenon can be divided into two types, static and dynamic denting. Static dent case covers scenario wherein interaction with outer panel is mostly quasi-static. Hail stones present dynamic case where object hits a panel with certain kinetic energy. Automotive companies usually perform static dent assessment to cover all the cases.

Structural adhesive is a good alternative to provide required strength at joinery of similar and dissimilar materials. Adhesive joinery plays a critical role to maintain structural integrity during vehicle crash scenario. Robust adhesive failure definitions are critical for accurate predictions of structural performance in crash Computer Aided Engineering (CAE) simulations. In this paper, structural adhesive material characterization challenges like comprehensive In-house testing and CAE correlation aspects are discussed. Considering the crash loading complexity, test plan is devised for identification of strength and failure characteristics at 0°, 45°, 75°, 90°, and Peel loading conditions. Coupon level test samples were prepared with high temperature curing of structural adhesive along with metal panels. Test fixtures were prepared to carryout testing using Instron VHS machine under quasi-static and dynamic loading.

Engine Stop/Start System (ESS) promises to reduce greenhouse emissions and improve fuel economy of vehicles. Previous work of the Authors was concentrated on bridging the gap of improvement in fuel economy promised by ESS under standard laboratory conditions and actual driving conditions. Findings from the practical studies lead to a conclusion that ESS is not so popular among the customers, due to the complexities of the system operation and poor integration of the system design with the driver behavior. In addition, due to various functional safety requirements, and traffic conditions, actual benefits of ESS are reduced. A modified control algorithm was proposed and proven for the local driving conditions in India. The ways in which a given driver behaves on the controls of the vehicles like Clutch and Brake Pedals, Gear Shift Lever were not uniform across the demography of study and varied significantly.

Authors were challenged with a task of developing a full vehicle simulation model, with a target to simulate the electrical system performance and perform digital tests like Battery Charge Balance, in addition to the fuel efficiency estimation. A vehicle is a complicated problem or domain to model, due to the complexities of subsystems. Even more difficult task is to have a control algorithm which controls the vehicle model with the required control signals to follow the test specification. Particularly, simulating the control of a vehicle with a manual transmission is complicated due to many associated control signals (Throttle, Brake and Clutch) and interruptions like gear changes. In this paper, the development of a full vehicle model aimed at the assessment of electrical system performance of the vehicle is discussed in brief.

During cabin warm-up, effective air distribution by vehicle climate control systems plays a vital role. For adequate visibility to the driver, major portion of the air is required to be delivered through the defrost center ducts to clear the windshield. HVAC unit deliver hot air with help of cabin heater and PTC heater. When hot air interacts with cold windshield it causes thermal losses, and windshield act as sink. This process may causes in delay of cabin warming during consecutive cabin warming process. Thus it becomes essential to predict the effect of different windscreen defrost characteristics. In this paper, sensitivity analysis is carried for different windscreen defrosts characteristics like ambient conditions, modes of operation; change in material properties along with occupant thermal comfort is predicted. An integrated 1D/3D CFD approach is proposed to evaluate these conditions.

The unit analysis methodology can be used for designing component or product in a product development process. This method may be used for designing the crush can, bumper beam, crush can long member, B-frame or A-pillar in frontal impact analysis. Unit assembly model technique can be effectively used in many CAE load cases to evaluate CAE simulations such as pedestrian impact analysis (ECE R78 / ENCAP), interior trim related head impact simulations (FMVSS201U), under run protection simulation for commercial vehicles (Front Underrun Protection Device ECE R93, Rear Underrun Protection Device ECE R58, Side Underrun Protection Device ECE R73), airbag deployment optimization etc. These CAE analyses correlate better with actual test. This paper gives idea about how the cost of product design can be reduced by using unit analysis. To reduce time of vehicle development such as cost of prototype, testing cost, optimization cost unit analysis is more economical.

Due to increased awareness by customer perceived sound characteristics, advance simulation technique emerged in NVH domain for mid-high frequency like BEM, Hybrid and Statistical Energy Analysis (SEA). One of the most widely and accepted practice in high frequency NVH is SEA technique to assess and optimize acoustic sound pack for Air Borne Noise (ABN) in the range of 400 Hz to 6300 Hz typically for Powertrain and Tyre Patch Noise Reduction. As Prof. Lyon states that “The most obvious disadvantage of statistical approaches is that they give statistical answers, which are always subject to some uncertainty” [1]. It is always challenge for SEA engineer to get correlation for full vehicle level model for Tyre Patch Noise Reduction (TPNR) and Powertrain Acoustic Transfer Function (PT ATF) to acceptable level. Appropriate correlated SEA model is developed and few challenges associated with SEA modeling are also discussed in this paper.

Ashcan contributes to the aesthetics and elegance of the vehicle interiors. It is used to store the ash. Generally the ashcan is fitted on the console of the car. The operational requirement of ashcan is to open with minimum force but not at very low accelerations experienced during the vehicle bump event. Also closing force should be comparatively higher. The closing of the ashcan lid should ensure positive locking, which may be achieved by using cam and follower locking mechanism. The other requirement is that it should be structurally durable enough to sustain the repetitive loading during its operation. Ashcan may undergo severe abusive loading during its operation. To simulate these operations and understand the physics of the problem, a multi-step non-linear analysis involving a complex contact situation is carried out. The scope of this paper is to explain the procedure of calculating the force required for closing and opening of the ashcan lid.

The purpose of Federal Motor Vehicle Safety Standard 216 is to reduce fatalities and serious injuries when vehicle roof crushes into occupant compartment during rollover crash. Upgraded roof crush resistance standard (571.216a Standard No. 216a) requires vehicle to achieve maximum applied force of 3.0 times unloaded vehicle weight (UVW) on both driver and passenger sides of the roof. (For vehicles with gross vehicle weight rating ≤ 6,000 lb.) This paper provides an overview of current approach for dual side roof strength Finite Element Analysis (FEA) and its limitations. It also proposes a new approach based on powerful features available in virtual tools. In the current approach, passenger side loading follows driver side loading and requires two separate analyses before arriving at final assessment. In the proposed approach only one analysis suffices as driver and passenger side loadings are combined in a single analysis.

In India, small car segment is having maximum sale, which includes cars like Maruti 800, SUZUKI Swift, Maruti Alto, Tata Indica, etc. Driver seat is one of the main aspects to be considered while defining comfort in a moving vehicle. The current analysis concentrates on driver seat because driver comfort is of main concern since it is the most occupied seat in any vehicle and the occupancy is for longer duration. In addition to sitting, the driver's job is to manipulate different controls and concentrate parallely on many aspects. The research work aims at studying the vertical vibrations transferred to the human body via seat. The work is an attempt towards studying dynamic characteristics of driver seat for comfort through objective evaluation. For objective evaluation, two tests were conducted; Seat Effective Amplitude Transmissibility (SEAT) test and Ride Comfort Index test under two different conditions, i.e., car level and seat level testing on Car "A" and Car "B."

The brake system is one of the most critical systems in the automotive vehicle. Its design is a challenging task since stringent performance and packaging requirements are to be fully met - optimizing the brake performance and weight of the brake system. The brake disc is an important component in the braking system which is expected to withstand and dissipate the heat generated during the braking event. Validation of brake disc design through CAE/FEA is presented in this paper. The procedure for prediction of thermal performance was developed in-house, tuned and verified by correlating with Test data available for existing-design and then applied to the new-design brake disc. The correlation achieved for the existing-design brake disc (both solid and ventilated), procedure for prediction of thermo-mechanical performance (heat transfer coefficient estimation, temperature distribution etc.) are also included.