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Current generation automobiles are controlled by electronic modules for performing various functions. These electronic modules have numerous semiconductor devices mounted on printed circuit boards. Solders are generally used as thermal interface material between surface mount devices and printed circuit boards (PCB) for efficient heat transfer. In the manufacturing stage, voids are formed in solders during reflow process due to outgassing phenomenon. The presence of these voids in solder for power packages with exposed pads impedes heat flow and can increase the device temperature. Therefore it is imperative to understand the effect of solder voids on thermal characteristics of semiconductor devices. But the solder void pattern will vary drastically during mass manufacturing. Replicating the exact solder void pattern and doing detail simulation to predict the device temperature for each manufactured module is not practical.

Delphi is developing a new combustion technology called Gasoline Direct-injection Compression Ignition (GDCI), which has shown promise for substantially improving fuel economy. This new technology is able to reuse some of the controls common to traditional spark ignition (SI) engines; however, it also requires several new sensors and actuators, some of which are not common to traditional SI engines. Since this is new technology development, the required hardware set has continued to evolve over the course of the project. In order to support this development work, a highly capable and flexible electronic control system is necessary. Integrating all of the necessary functions into a single controller, or two, would require significant up-front controller hardware development, and would limit the adaptability of the electronic controls to the evolving requirements for GDCI.

Bond wires are used in automotive electronic modules to carry current from external harness to components where flexibility under thermal cyclic loading is very essential between PCB (Printed Circuit Board) and connectors. They are very thin wires (few μm) made up of gold, aluminum or copper and have to undergo mechanical reliability to withstand extreme mechanical and thermal loads during different vehicle operation scenarios. Thermal reliability of bond wire is to make sure that it can withstand prescribed electric current under given boundary conditions without fusing thereby retaining electronic module's functionality. While carrying current, bond wire by virtue of its nature resists electric current flow and generates heat also called as joule heating. Joule heating is proportional to current flow and electrical resistance and if not handled properly can lead to thermal run away conditions.

The present paper reports on a study of the HVAC energy usage for an EREV (extended range electric vehicle) implementation of a localized cooling/heating system. Components in the localized system use thermoelectric (TE) devices to target the occupant's chest, face, lap and foot areas. A novel contact TE seat was integrated into the system. Human subject comfort rides and a thermal manikin in the tunnel were used to establish equivalent comfort for the baseline and localized system. The tunnel test results indicate that, with the localized system, HVAC energy savings of 37% are achieved for cooling conditions (ambient conditions greater than 10 °C) and 38% for heating conditions (ambient conditions less than 10 °C), respectively based on an annualized ambient and vehicle occupancy weighted method. The driving range extension for an electric vehicle was also estimated based on the HVAC energy saving.

In recent years, a number of key influences are contributing to accelerate technological innovation in the automotive industrial sector. Concerns about renewable energy resource, fossil-fuels crises and higher gasoline prices, global warming awareness and environmental impacts, scarcity of minerals/metals and electronics demands rising are some of the major challenges for vehicle automakers and their suppliers. The interest in alternative fuel vehicles, especially hybrid-electrical vehicles (HEV) or renewable energy power concepts for road vehicles has become intensified and represents a significant area of research and development in order to meet nowadays global demands. However because of Hybrid Vehicles unique Power Supply System the electrical/electronic architecture (E/E) is sophisticated, requesting more robust sealing and a particular wiring harness components, such as connector, terminals and cables.

In vehicular mobility context, it is extremely important for the environmental sustainability that the available energy will be used as efficiently as possible, both in the use of internal combustion engines (ICE) as powertrain, as well in the application of Hybrid and Electric Vehicle Motors (HEV/EV). In this comparison, ICE has a lower efficiency when compared to electric motors, wasting much of the potential energy of the fuel in form of heat and noise. On the other hand, the electric vehicles face limitation in autonomy and recharge time, demanding for a more efficient use of energy stored in batteries. This study aims to present emerging technologies for reuse of energy within the automotive context, originally known as “Energy Harvesting” and “Renewable Energies”.

Miniaturization is an important trend in many technology segments, once it can enable innovative applications generating new markets. This trend was begun in electronics industry after World War II and has spawned changes into automotive sector also. For Automotive Wiring Harness, miniaturization is clearly presented in most of the components, mainly because of its benefits like the potential of mass reduction, cost reduction and efficiency improvement. Furthermore the main voice of customer points to cable gauge reduction that represents a considerable challenge for connection manufacturing process due to quality control limitations presented by conventional crimp process for 0,35 [mm₂] cables and smaller. According to that, the scope of this article is to present, in details, a manufacturing process optimization for an alternative and more robust technology of joining copper stranded cables to tin brass terminals used on automotive wiring harness, Resistance Welding.

While the potential emissions and efficiency benefits of HCCI combustion are well known, realizing the potentials on a production intent engine presents numerous challenges. In this study we focus on identifying challenges and opportunities associated with a production intent cam-based variable valve actuation (VVA) system on a multi-cylinder engine in comparison to a fully flexible, naturally aspirated, hydraulic valve actuation (HVA) system on a single-cylinder engine, with both platforms sharing the same GDI fueling system and engine geometry. The multi-cylinder production intent VVA system uses a 2-step cam technology with wide authority cam phasing, allowing adjustments to be made to the negative valve overlap (NVO) duration but not the valve opening durations. On the single-cylinder HVA engine, the valve opening duration and lift are variable in addition to the NVO duration. The content of this paper is limited to the low-medium operating load region at 2000 rpm.

Spot, or distributed, cooling and heating is an energy efficient way of delivering comfort to an occupant in the car. This paper describes an approach to distributed cooling in the vehicle. A two passenger CFD model of an SUV cabin was developed to obtain the solar and convective thermal loads on the vehicle, characterize the interior thermal environment and accurately evaluate the fluid-thermal environment around the occupants. The present paper focuses on the design and CFD analysis of the energy efficient HVAC system with spot cooling. The CFD model was validated with wind tunnel data for its overall accuracy. A baseline system with conventional HVAC air was first analyzed at mid and high ambient conditions. The airflow and cooling delivered to the driver and the passenger was calculated. Subsequently, spot cooling was analyzed in conjunction with a much lower conventional HVAC airflow.

The development of an analytical model for multilayer stack subjected to temperature change is demonstrated here. Thin continuous layers of materials bonded together deform as a plate due to their differing coefficients of thermal expansion upon subjecting the bonded materials to the change in temperature. Applications of such structures can be found in the electronics industry (the study of warpage issues in printed circuit boards) or in the aerospace industry as (the study of laminated thin sheets used as skin structures for load bearing members such as wings and fuselage). In automotive electronics, critical high-power packages (IGBT, Power FETs) include several layers of widely differing materials (aluminum, solder, copper, ceramics) subjected to wide temperature cyclic ranges. Modeling of such structures by using three-dimensional finite element methods is usually time consuming and may not exactly predict the inter-laminar strains.

The success of stratified combustion is strongly determined by the injection and ignition system used. A large temporal and spatial variation of the main parameters - mixture composition and charge motion - in the vicinity of the spark location are driving the demands for significantly improved ignition systems. Besides the requirements for conventional homogeneous combustion systems higher ignition energy and breakdown voltage capability is needed. The spark location or spark plug gap itself has to be open and well accessible for the mixture to allow a successful flame kernel formation and growth into the stratified mixture regime, while being insensitive to potential interaction with liquid fuel droplets or even fuel film. For this purpose several different ignition concepts are currently being developed. The present article will give an ignition system overview for stratified combustion within Delphi Powertrain Systems.

CFD analysis was performed using the FLUENT software to design the thermal system for a hybrid vehicle battery pack. The battery pack contained multiple modular battery elements, called bricks, and the inlet and outlet bus bars that electrically connected the bricks into a series string. The simulated thermal system was comprised of the vehicle cabin, seat cavity, inlet plenum, battery pack, a downstream centrifugal fan, and the vehicle trunk. The fan was modeled using a multiple reference frame approach. A full system analysis was done for airflow and thermal performance optimization to ensure the most uniform cell temperatures under all operating conditions. The mesh for the full system was about 13 million cells run on a 6-node HP cluster. A baseline design was first analyzed for fluid-thermal performance. Subsequently, multiple design iterations were run to create uniform airflow among all the individual bricks while minimizing parasitic pressure drop.

This paper presents the further development of an electro-hydraulic camless valve actuation system for internal combustion engines. The system (Hydraulic Valve Control - HVC) is an open loop device for engine valve fully flexible camless actuation. Valve timing and duration are controlled by a pilot stage governed by a solenoid, fast-acting, three-way valve. Valve lift is controlled by varying the oil pressure of the power stage. The system exploits an energy recovery working principle that plays a significant role in reducing the power demand of the whole valve train. In the present paper a new HVC actuator design is presented and its performances in terms of valve lift profile, repeatability and landing are discussed. Experimental data obtained by the application of the HVC system to a motored, single-cylinder research engine have been used to support the numerical evaluation of the potentialities of non-conventional valve actuation in engine part-load operation.

This paper describes how a fully three-dimensional CFD model was used to investigate the turbulence generation mechanisms of an unthrottled 4 valve SI engine operating with different intake valve lift strategies (symmetric and asymmetric). In the context of Early Intake Valve Closure (EIVC) strategies, the aim of the work is to highlight the potentialities to increase turbulence levels also at light load using asynchronous intake valve lift, thus promoting both tumble and swirl motions. Six simulations are presented, four at low engine speed (2500 rpm) and two at high speed (6000 rpm, that serve as reference), concerning an SI engine at full and light load, with symmetric and asymmetric intake lifts. One of these simulations was executed in standard throttling conditions. The CFD transient simulations involved three strokes of the engine: exhaust, intake and compression up to combustion TDC. 1D data are used for boundary and initial conditions.

Brazilian automotive market has been growing faster than ever. In order to react properly to market increasing demand in terms of volume and diversity, production systems have to be carefully designed. Traditional manufacturing tends to react to demand increase by outsourcing or investing in new equipments or facilities. Lean thinking suggests that by reducing waste along the value stream it is possible to increase flexibility and freed resources to reduce the investment level required to cope customer’s needs. This paper presents two cases of a system redesign based on the lean manufacturing principles to support the demand.

This paper is about the use of the Six Sigma Methodology, to solve variation problems in the manufacture area, at one of the Delphi Automotive Systems unit that manufacturer electrical harness. The DMAIC framework was followed, the improvements were done, eliminating the rots causes, and the use of Six Sigma methodology, was showed very efficient in solve problems. The methodology power, is in using a structured frame work, the DMAIC (Define-Measure-Analyze-Improve-Control), completing by quality quality tools (Pareto Chart, Five Why's, Cause and Effect Diagram) and statistical analyses, for example: variance analyses, hypotheses tests and Design of Experiments.

Among variable valve actuation systems, fully flexible systems such as camless devices are the most attractive valvetrains for near-future engines. This paper presents a research activity about an electro-hydraulic camless system for internal combustion engines. The Hydraulic Valve Control (HVC) system uses hydraulic forces to open the valve while a mechanical spring is used for the closure. The system is fed by an hydraulic pump and two pressure regulators which provide two different pressure levels: a high pressure level (approximately 100 bar) for the pilot stage and a low adjustable pressure level (from 20 to 90 bar) for the actuator power stage. The valve opening duration is controlled by varying the timing of the opening signal of the pilot stage; the valve lift is adjusted varying the oil pressure of the power stage. From a general point of view, the HVC system is an open loop device for engine valve actuation.

Delphi's Zero Resistance Technology (ZRT) is a revolutionary new product/process that enables the reduction of mass and volume from a traditional wiring assembly. ZRT is defined as a minimal (zero) resistance change over time. The ZRT product is an electrical/electronic connection system which provides a viable solution for high density and limited space wiring applications. The ZRT process is a semi-automated wiring harness manufacturing system with flexibility to produce harnesses to the customer demand.

Modeling and studies on reed valve devices are topics often dealt with when designing internal combustion engine intake and exhaust systems. This paper describes an activity about the modeling and the optimization potentiality of an engine equipped with a secondary air injection system by means of a reed valve device. The first step of the work dealt with the development and tuning of a non-linear Finite Element model of reed valve and with the integration of this model into a one-dimensional fluid-dynamics simulation code. In particular during this phase the potentialities of the method were tested by implementing the FE model both in a 1D University code and in a 1D commercial code (by means of a provided interface for User Defined Elements). In the second step of the work the simulation results were analyzed for different engine operating points.

For A/C and cooling systems development is usual send vehicles to US or Europe for wind tunnel tests, witch is expensive and has a long lead-time. Here in Brazil Delphi has at the Piracicaba Technical Center a chamber equipped with temperature control and chassis dynamometer. There is a up-grade project for it that consist in add ducts with fans inside the chamber that will get air from the chamber, already in the right temperature, accelerate and homogenate the air flow and blow it out direct to the front end of the vehicle. For development purposes may be possible eliminate totally the necessity of sending vehicle abroad. It was then decided to use CFD simulation to predict firstly the required fan power necessary to supply winds until 120 km/h at the front end of the vehicle and secondly predict the airflow pattern inside the chamber, considering chamber inlet air, chamber outlet air, exhaust outlet, duct outlet and flow pattern around the vehicle.