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This paper presents a methodology for predicting thermal comfort inside Midibus cabin with an objective to modify the Heating, Ventilation and Air Conditioning (HVAC) duct design and parametric optimization in order to have improved thermal comfort of occupant. For this purpose the bus cavity is extracted from baseline CAD model including fully seated manikins with various seating positions. Solar Load has been considered in the computational model and passenger heat load is considered as per BSR/ASHRAE 55-1992R standard. CFD simulation predicted the air temperature and velocity distribution inside passenger cabin of the baseline model. The experimental measurements have been carried out as per the guidelines set in APTA-BT-RP-003-07 standard. The results obtained from CFD and Experimental test were analysed as per EVS EN ISO7730 standard and calculated occupant comfort in terms of thermal comfort parameters like Predicted Mean Vote (PMV) and Predicted Percentage Dissatisfied (PPD).

The death toll due to traffic accidents in India is on a rise, according to the latest Road Transport ministry report, a total of 4.97 lakh road accident was reported in 2011. Though compared to 2010, the accidents have gone down by 1,945, the number of deaths at 1,42,485 has increased by over 7,000.[1] This paper proposes a design of an Emergency Intimation System (EIS) tailored to fit for Indian consumer needs and available infrastructure. EIS is an emergency alert technology devised to assist drivers and passenger in an event of vehicle crash. Majority of deaths are caused by slow accident response time. EIS is aimed to lower this response time and ensure that the required rescue and medical services are made available in time. This device employed to make this emergency alerts will be fitted into the vehicle Electrical and Electronics (E/E) architecture and will have interfaces with crash sensor network, CAN network and GSM etc.

Hyperelastic material simulations are commonly performed in commercial FE codes due to availability of sophisticated algorithms facilitating virtual characterization of such materials in FEA easily. However, the solution time required is longer in FEA. Especially when excitation frequencies do not interfere with structural modes, flexible multibody simulation offers a lucrative and computationally inexpensive alternative. However, it is difficult to directly characterize hyperelastic materials in commercial MBS simulation codes, so the reduced solution time comes at the cost of decreased simulation accuracy, especially if the designer is provided with crude stress - strain test data. Hence, the need is to overcome the drawbacks in FEA and multibody codes, as well as to leverage best of both these codes simultaneously.

Designers and analysts need to compare and conduct synthesis for selection of materials based on their properties involving simulation, optimization and correlation with test data. An example is that of acoustic material properties such as random and normal incidence sound absorption coefficient and sound transmission loss. The international test standards necessitate having standard operating procedures for characterization of these materials. This procedure is quite involved and addresses steps including test data acquisition, post processing, calculations, classification, report generation and most importantly, storage of such innumerable material properties in a structured manner to facilitate ease of retrieval and updating of properties. It is also highly desirable to have a synergy of the databank directly with simulation tools. Further, all of these steps need to be accurate, non-speculative and quick.

Gerotor pump is a positive displacement pump unit which is widely used for lubrication in on-road and off-road engine applications. This paper is focused on Gerotor pump design competency established at ARAI comprising of design of inner and outer rotors, suction & delivery ports, optimizing inlet and outlet diameters & its position, development of methodology to calculate oil flow rate, volumetric efficiency, mechanical efficiency & slippage. The finalization of design is followed by CFD of Gerotor pump to optimize the pressure and flow pulsation. A trochoidal profile is used to design the inner and outer rotors and its conjugate profile are realized by a set of equations using a method based on the theory of gearing. Suction and delivery port is analytically designed based on the same design parameters of the trochoidal profile.

An open wheeled open cockpit high speed car with 800 CC MPFI engine was developed validated and run at 105 kmph. The key focus was to build a car with superior aerodynamic characteristics especially in terms of drag. This work discusses in detail about the design and simulation of car using CFD package followed by Wind Tunnel testing. The design of high speed car starts with design of seat according to the ergonomics of the driver followed by the space frame. Based on the space frame designed, the body panels are sketched and CAD model is developed. The CAD model is imported in CFD package for virtual testing and validated through wind tunnel results. For this 1:3 scale model was manufactured using Rapid Prototyping.

In order to reduce development time and costs, application of numerical prediction techniques has become common practice in the automotive industry. Among the wide range of simulation applications, prediction of the vehicle interior noise is still one of the most challenging ones. The Finite Element Method (FEM) is well known for acoustic predictions in the low-frequency range. As part of the development of a full sized bus model, noise levels at Driver Ear Levels (DEL) and Passenger Ear Levels (PEL) were targeted. The structural and acoustic analysis were performed for a bus to reduce interior noise in the low-frequency range. Various counter measures were identified and structural optimization/modifications were performed from virtual simulation to reduce the DEL and PEL. Structure-borne noise due to both road-induced vibration and engine vibration were considered by using FEM techniques.

Passive safety regulations specify minimum safety performance requirements of vehicle in terms of protecting its occupants and other road users in accident scenarios. Currently for majority cases, the compliance of vehicle design to passive safety regulations is assessed through physical testing. With increased number of products and more comprehensive passive safety requirements, the complexity of certification is getting challenged due to high cost involved in prototype parts and the market pressures for early product introduction through reduced product development timelines. One of the ways for addressing this challenge is to promote CAE based certification of vehicle designs for regulatory compliance. Since accuracy of CAE predictions have improved over a period of time, such an approach is accepted for few regulations like ECE-R 66/01, AIS069 etc which involves only loadings of the structures.

This work is a part of program on “Development of High Performance DI, 3 Cylinder CRDI Diesel Engine to meet Euro-IV/V Emission Norms focused on automotive passenger car application purpose. This is a 3 Cylinder, TCIC engine designed for combustion pressure of 160 bar max for first stage which is being upgraded to 200 bar max in the second stage. Cylinder Head design is a part of complicated configuration whose construction and principal dimensions are dependent on the size of inlet and exhaust valves, fuel injectors positioning and mounting, port layout and swirl and shape of combustion chambers. The cylinder head of a direct-injection diesel engine has to perform many functions. It has to bring charge air to the cylinder and exhaust gas from the cylinder, with minimum pumping loss and required swirl and other properties of charge motion.