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Stringent automotive legislation is driving requirements for increasingly complex battery pack solutions. The key challenges for battery pack development drive cost and performance optimisation, growth in architecture solutions, monitoring and safety through lifetime, and faster-to-market expectations. The battery Virtual Product Development (VPD) toolchain addresses these challenges and provides a solution to reduce the battery pack development time, cost and risk. The battery VPD toolchain is built upon scalable, validated sub-models of the battery pack that capture the interactions between the various domains; mechanical, electrical, thermal and hydraulic. The model fidelity can be selected at each stage of the design process allowing the right amount of detail, and available data, to be incorporated. The toolchain is coupled with vehicle simulation tools to rapidly assess performance of the complete electrified powertrain.

A Range-Extended Electric Vehicle (REEV) usually has an auxiliary power source that can provide additional range when the main Rechargeable Energy Storage System (RESS) runs out. The range extender can be a fuel cell, a gas turbine, or an Internal Combustion Engine (ICE) bolted to a generator. Sizing the powertrain for a REEV is primarily to investigate the relationship between the capacity of the main RESS and the power rating of the range extender. Worldwide harmonized Light vehicles Test Procedures (WLTP) introduced a Utility Factor (UF) which is a curve used to calculate the weighted test results for the Off-Vehicle Charging-Hybrid Electric Vehicle (OVC-HEV) from the measured Charge Depleting (CD) mode range result, and the Charge Sustaining (CS) mode Fuel Consumption (FC). Therefore, the RESS capacity, the range extender power rating, the control strategy, and the UF are the key factors affecting the weighted FC of a REEV on the test cycle.

Most major regional automotive markets have stringent legislative targets for vehicle greenhouse gas emissions or fuel economy enforced by fiscal penalties. Large improvements in vehicle efficiency on mandated test cycles have already taken place in some markets through the widespread adoption of technologies such as downsizing or dieselization. There is now increased focus on approaches which give smaller but significant incremental efficiency benefits such as reducing parasitic losses due to engine friction. Fuel economy improvements which achieve this through the development of advanced engine lubricants are very attractive to vehicle manufacturers due to their favorable cost-benefit ratio. For an engine with components which operate predominantly in the hydrodynamic lubrication regime, the most significant lubricant parameter which can be changed to improve the tribological performance of the system is the lubricant viscosity.

Fuel consumption, and the physical behaviours behind it, have never been of greater interest to the automotive engineering community. The enormous design, development and infrastructure investment involved with a new engine family which will be in production for many years demands significant review of the base engine fundamental architecture. Future CO2 challenges are pushing car manufacturers to consider alternative engine configurations. As a result, a wide range of diesel engine architectures are available in production, particularly in the 1.4 to 1.6 L passenger car market, including variations in cylinder size, number of valves per cylinder, and bore:stroke (B/S) ratio. In addition, the 3 cylinder engine has entered the market in growing numbers, despite its historic NVH concerns. Ricardo has performed a generic architecture study for a midsize displacement engine in order to assess the pros and cons of each engine configuration.

Controlled Auto-Ignition (CAI) combustion, also known as Homogeneous Charge Compression Ignition (HCCI), has the potential to simultaneously reduce the fuel consumption and nitrogen oxides emissions of gasoline engines. However, narrow operating region in loads and speeds is one of the challenges for the commercial application of CAI combustion to gasoline engines. Therefore, the extension of loads and speeds is an important prerequisite for the commercial application of CAI combustion. The effect of intake charge boosting, charge stratification and spark-assisted ignition on the operating range in CAI mode was reviewed. Stratified flame ignited (SFI) hybrid combustion is one form to achieve CAI combustion under the conditions of highly diluted mixture caused by the flame in the stratified mixture with the help of spark plug.

In this paper, an experimental study was performed to investigate characteristics of flame propagation and knocking combustion of hydrous (10% water content) and anhydrous ethanol at different air/fuel ratios in comparison to RON95 gasoline. Experiments were conducted in a full bore overhead optical access single cylinder port-fuel injection spark-ignition engine. High speed images of total chemiluminescence and OH* emission was recorded together with the in-cylinder pressure, from which the heat release data were derived. The results show that under the stoichiometric condition anhydrous ethanol and wet ethanol with 10% water (E90W10) generated higher IMEP with at an ignition timing slightly retarded from MBT than the gasoline fuel for a fixed throttle position. Under rich and stoichiometric conditions, the knock limited spark timing occurred at 35 CA BTDC whereas both ethanol and E90W10 were free from knocking combustion at the same operating condition.

Poppet-valve two-stroke gasoline engines can increase the specific power of their four-stroke counterparts with the same displacement and hence decrease fuel consumption. However, knock may occur at high loads. Therefore, the combustion with stratified lean mixture was proposed to decrease knock tendency and improve combustion stability in a poppet-valve two-stroke direct injection gasoline engine. The effect of intake pressure and split injection on fuel distribution, combustion and knock intensity in lean mixture conditions at high loads was simulated with a three-dimensional computational fluid dynamic software. Simulation results show that with the increase of intake pressure, the average fuel-air equivalent ratio in the cylinder decreases when the second injection ratio was fixed at 70% at a given amount of fuel in a cycle.

The aim of this study is to evaluate the Fuel Economy (FE) over the driving cycle for a 48 Volt P2 technology vehicle with different component ratings (battery and electric machine) in the hybrid powertrain, using simulation and Design of Experiments (DoE) tools. The P2 architecture was selected for this study based on an initial assessment of a wide number of possibilities, using the Ricardo “Architecture Independent Modelling (AIM)” toolset. This allows rapid evaluation of different powertrain options independently of a defined hybrid control strategy. For the vehicle with P2 architecture, a DoE test matrix of battery capacity and electric machine power rating was created. The test matrix was then imported into the simulation environment to perform the driving cycle FE simulations. Then, a 48 V P2 Hybrid Electric Vehicle (HEV) FE emulator model was created and interrogated using model visualisation and optimisation methods.

Rolling element bearings are known to give reduced friction losses when compared to the hydrodynamic bearings typically used to support the crankshaft in multi-cylinder engines. This paper describes the design, manufacturing and testing of a modified 4 cylinder light duty Diesel production engine with rolling element bearings applied at the crankshaft main bearings in view of CO2 emission reduction. Selection of the most suitable type of roller bearings for this specific application was made. Technology development through multi-body dynamic simulation and component testing was done to assess the effect on rolling elements performance due to the key challenges inherent to such bearing solution: high instantaneous combustion load, lubrication with low viscosity and contaminated oil, and the cracking process to split the bearing outer raceway.

An experimental study has been carried out with the end goal of minimizing engine-out methane emissions with Premixed Micro Pilot Combustion (PMPC) in a natural gas-diesel Dual-Fuel™ engine. The test engine used is a heavy-duty single cylinder engine with high pressure common rail diesel injection as well as port fuel injection of natural gas. Multiple variables were examined, including injection timings, exhaust gas recirculation (EGR) percentages, and rail pressure for diesel, conventional Dual-Fuel, and PMPC Dual-Fuel combustion modes. The responses investigated were pressure rise rate, engine-out emissions, heat release and indicated specific fuel consumption. PMPC reduces methane slip when compared to conventional Dual-Fuel and improves emissions and fuel efficiency at the expense of higher cylinder pressure.

Future demands for very low emissions from diesel engines, without compromising fuel economy or driveability, require Engine Management Systems (EMS) capable of compensating for emissions dispersion caused by production tolerances and component ageing. The Advanced Diesel Engine Control (ADEC) Project, a collaboration between Ricardo and General Motors, is aimed at reducing engine-out emissions dispersion and enabling alternative combustion modes, such as Highly Premixed Cool Combustion (HPCC), in real-world scenarios. This is being achieved by high-level co-ordination of fuel, air and EGR in order to meet the conflicting performance requirements of current and future diesel engines. A sensor feasibility study was undertaken which included a number of new sensing technologies appropriate for future mass production. Two sensor types, namely cylinder pressure and accelerometer sensors, were then selected to demonstrate varying degrees of benefits versus sensor technology cost.

Engine downsizing is one of the most effective means to improve the fuel economy of spark ignition (SI) gasoline engines because of lower pumping and friction losses. However, the occurrence of knocking combustion or even low-speed pre-ignition at high loads is a severe problem. One solution to significantly increase the upper load range of a 4-stroke gasoline engine is to use 2-stroke cycle due to the double firing frequency at the same engine speed. It was found that a 0.7 L two-cylinder 2-stroke poppet valve gasoline engine equipped with a two-stage serial boosting system, comprising a supercharger and a downstream turbocharger, could replace a 1.6 L naturally aspirated 4-stroke gasoline engine in our previous research, but its fuel economy was close to that of the 4-stroke engine at upper loads due to knocking combustion.

In-cylinder flow was optimised in a three-valve twin-spark-plug SI engine in order to obtain good two-zone fuel fraction stratification in the cylinder by means of tumble flow. First, the in-cylinder flow field of the original intake system was measured by Particle Image Velocimetry (PIV). The results showed that the original intake system did not produce large-scale in-cylinder flow and the velocity value was very low. Therefore, some modifications were applied to the intake system in order to generate the required tumble flow. The modified systems were then tested on a steady flow rig. The results showed that the method of shrouding the lower part of the intake valves could produce rather higher tumble flow with less loss of the flow coefficient than other methods. The optimised intake system was then consisted of two shroud plates on the intake valves with 120° angles and 10mm height. The in-cylinder flow of the optimised intake system was investigated by PIV measurements.

The outward-opening piezoelectric injector can achieve stable fuel/air mixture distribution and multiple injections in a single cycle, having attracted great attentions in direct injection gasoline engines. In order to realise accurate predictions of the gasoline spray with the outward-opening piezoelectric injector, the computational fluid dynamic (CFD) simulations of the gasoline spray with different droplet breakup models were performed in the commercial CFD software STAR-CD and validated by the corresponding measurements. The injection pressure was fixed at 180 bar, while two different backpressures (1 and 10 bar) were used to evaluate the robustness of the breakup models. The effects of the mesh quality, simulation timestep, breakup model parameters were investigated to clarify the overall performance of different breakup model in modeling the gasoline sprays.

Low combustion efficiency and high hydrocarbon emissions at low loads are key issues of natural gas and diesel (NG-diesel) dual fuel engines. For better engine performance, two diesel-spray-orientated (DSO) bowls were developed based on the existing diesel injector of a heavy-duty diesel engine with the purpose of placing more combustible natural gas/air mixture around the diesel spray jets. A protrusion-ring was designed at the rim of the piston bowl to enhance the in-cylinder flame propagation. Numerical simulations were conducted for a whole engine cycle at engine speed of 1200 r/min and indicated mean effective pressure (IMEP) of 0.6 MPa. Extended coherent flame model 3 zones (ECFM-3Z) combustion model with built-in soot emissions model was employed. Simulation results of the original piston bowl agreed well with the experimental data, including in-cylinder pressure and heat released rate (HRR), as well as soot and methane emissions.

The increasing concern about CO2 emissions and energy prices has led to new CO2 emission and fuel economy legislation being introduced in world regions served by the automotive industry. In response, automotive manufacturers and Tier-1 suppliers are developing a new generation of internal combustion (IC) engines with ultra-low emissions and high fuel efficiency. To further this development, a better understanding is needed of the combustion and pollutant formation processes in IC engines. As efficiency and emission abatement processes have reached points of diminishing returns, there is more of a need to make measurements inside the combustion chamber, where the combustion and pollutant formation processes take place. However, there is currently no good overview of how to make these measurements.

The Controlled Auto-Ignition (CAI) combustion, also known as Homogeneous Charge Compression Ignition (HCCI) can be achieved by the negative valve overlap method in conjunction with direct injection in a four-stroke gasoline engine. A multi-cycle 3D engine simulation program has been developed and applied to study the effect of injection timing on CAI operations with lean and stoichiometric mixtures. The combustion models used in the present study are based on the modified Shell auto-ignition model and the characteristic-time combustion model. A liquid sheet breakup spray model was used for the droplet breakup processes. Based on the parametric studies on injection timing and equivalence ratio, the major difference between stoichiometric and lean-burn CAI operations is due to the fact that fuel injections take place during the negative valve overlap period.

A multi-cycle three-dimensional CFD engine simulation programme has been developed and applied to analyze the Controlled autoignition (CAI) combustion, also known as homogeneous charge compression ignition (HCCI), in a direct injection gasoline engine. CAI operation was achieved through the negative valve overlap method by means of a set of low lift camshafts. The effect of single injection timing on combustion phasing and underlying physical and chemical processes involved was examined through a series of analytical studies using the multi-cycle 3D engine simulation programme. The analyses showed that early injection into the trapped burned gases of a lean-burn mixture during the negative valve overlap period had a large effect on combustion phasing, due to localized heat release and the production of chemically reactive species. As the injection was retarded to the intake stroke, the charge cooling effect tended to slow down the autoignition process.

The purpose of the 4-SPACE (4-Stroke Powered gasoline Auto-ignition Controlled combustion Engine) industrial research project is to research and develop an innovative controlled auto-ignition combustion process for lean burn automotive gasoline 4-stroke engines application. The engine concepts to be developed could have the potential to replace the existing stoichiometric / 3-way catalyst automotive spark ignition 4-stroke engines by offering the potential to meet the most stringent EURO 4 emissions limits in the year 2005 without requiring DeNOx catalyst technology. A reduction of fuel consumption and therefore of corresponding CO2 emissions of 15 to 20% in average urban conditions of use, is expected for the « 4-SPACE » lean burn 4-stroke engine with additional reduction of CO emissions.

The use of diesel particulate filter [DPF] has become a standard in modern diesel engine after treatment technology. However pressure drop develops across the filter as PM accumulates and this requires quick periodic burn-out without incurring thermal runaway temperatures that could compromise DPF integrity during operation. Adequate understanding of soot oxidation is needed for design and manufacture of efficient filter traps for the engine system. In this study, we have examined the impact of blending biodiesel on oxidation of PM generated from a high speed direct injection [HSDI] diesel engine, which was operated with 20% [B20] and 40% [B40] blends of two biodiesel fuels. The PM samples were collected from the engine exhaust using a Pall Tissuquartz filter, the oxidation characteristics of the samples were carried out using thermogravimetric analyzer [TGA]. The biodiesel oxidation data obtained from pure petrodiesel was compared against the fuel blends.