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The warmup characteristics of an engine have an important impact on a variety of design issues such as performance, emissions and durability. A computer simulation has been developed which permits a detailed transient simulation of the engine warmup period from initial ambient conditions to a fully warmed up state. The simulation combines a detailed crankangle-by-crankangle calculation of in-cylinder processes and of engine air flow, with finite element heat conduction calculations of heat transfer from the gases, through the structure to the coolant. The paper describes one particular application of the simulation to the warmup of a 2.5ℓ spark ignited engine from cold start to a fully warmed up state at several speeds ranging from 1600 to 5200 rpm and loads ranging from 25% to 100% at each speed. The response of structure temperatures, charge temperature at IVC and of the exhaust temperature has been calculated and is documented in terms of characteristic warmup times.

Meeting the California Medium-Duty truck emissions standards presents a significant challenge to automotive engineers due to the combination of sustained high temperature exhaust conditions, high flow rates and relatively high engine out emissions. A successful catalyst for an exhaust treatment system must be resistant to high temperature deactivation, maintain cold start performance and display high three-way conversion efficiencies under most operating conditions. This paper describes a catalyst technology and precious metal loading study targeting a California Medium-Duty truck LEV (MDV2) application. At the same time a direction is presented for optimizing toward the Federal Tier 1 standard through reduction of precious metal use. The paper identifies catalytic formulations for a twin substrate, 1.23 L medium-coupled converter. Two are used per vehicle, mounted 45 cm downstream of each manifold on a 5.7 L V8 engine.

In the port injected Spark Ignition (SI) engine, the single greatest part load efficiency reducing factor are energy losses over the throttle valve. The need for this throttle valve arises from the fact that engine power is controlled by the amount of air in the cylinders, since combustion occurs stoichiometrically in this type of engine. In WEDACS (Waste Energy Driven Air Conditioning System), a technology patented by the Eindhoven University of Technology, the throttle valve is replaced by a turbine-generator combination. The turbine is used to control engine power. Throttling losses are recovered by the turbine and converted to electrical energy. Additionally, when air expands in the turbine, its temperature decreases and it can be used to cool air conditioning fluid. As a result, load of the alternator and air conditioning compressor on the engine is decreased or even eliminated, which increases overall engine efficiency.

Currently, in the typical internal combustion engine, approximately one third of fossil fuel combustion by-product is wasted heat. In the continued effort to improve fuel economy, one area that is being researched today is the harvesting of wasted energy to increase vehicle efficiency. This paper will address how heat emitted by exhaust systems can be captured and used to increase vehicle efficiency. Overall we will compare energy content in the exhaust manifold and exhaust underfloor mid-vehicle position, where potential exhaust heat exchanger concepts can reside. These heat exchanger concepts are designed primarily to capture heat from these locations and transfer the energy for increased passenger heating and comfort during cold conditions and/or supplement other improvements in power train efficiencies. An analysis of the energy exchange to the heated fluid is compared in the exhaust manifold and underfloor position respectively.

Rankine bottoming system, which operates on waste heat of engine cooling, has been developped to improve the fuel economy of a passenger car. Evaporative engine cooling system is utilized to obtain high thermal efficiency and simplicity of the Rankine bottoming system. The bottoming system uses HCFC123 as a working fluid, and scroll expander as a power conversion unit. The results indicate that energy recovery, which depends on the ambient temperature, is almost 3 percent of engine output power at ambient temperature of 25°C.

Turbocharging is becoming a key technology for automotive spark ignition engines (fed with both liquid and gaseous fuel) as a support to the downsizing concept in order to reduce fuel consumption and exhaust emissions. A waste-gate valve is usually fitted as turbocharger control system in these applications, due to its ability to work at very high exhaust gas temperatures. However, not much information is generally available on turbine behaviour in the opened waste-gate area. This paper presents the results of an experimental study developed on a waste-gated turbocharger for downsized SI automotive engines, performed on the test rig operating at the University of Genoa (Italy), extended both to steady and unsteady flow operation. Mass flow through the by-pass valve and turbine impeller was measured at different waste-gate settings in steady flow conditions.

Distributed generation represents a valid option for reducing transmission losses and overall power system complexity. Back-up power is another option that can ensure valuable safety margins in the scenario of extensive penetration of renewables, and can also act as balancing sources. Spark ignition (SI) engines are often the prime choice for such applications with sizes ranging from single cylinder configurations to large bore units. Augmenting control margins without increasing the number of sensors is an essential aspect for small size engines. Common practice for such power units is to employ fixed ignition timing with so called wasted spark systems, i.e. two events per cycle one during compression and one during the exhaust stroke. Nonetheless, application of more complex control systems such as fuel injection are becoming more and more widespread even for this engine category.

An experimental investigation of the underhood cooling airflow of a production passenger car has been carried out with a 3/8-scale model in a water filled tow tank at Texas Tech University and with a production vehicle in the Maritime Dynamics Laboratory tow basin of SSPA Maritime Consulting AB in Gothenburg, Sweden. The primary objectives for both the 3/8 and production vehicle investigations were to obtain a better understanding of the cooling airflow behavior within the engine compartment of an automobile and to identify the major factors influencing the flow field. The tests consisted of running a fan on a stationary and moving vehicle with pressure measurements and extensive flow visualizations within the engine bay.

The vehicle WLTP and RDE homologation test cycles are pushing the engine technology toward the implementation of different solutions aimed to the exhaust gases emission reduction. The tightening of the policy on the Auxiliary Emission Strategy (A.E.S.), including those for the engine component protection, faces the Spark Ignited (S.I.) engines with the need to replace the fuel enrichment as a means to cool down both unburnt mixture and exhaust gases to accomplish with the inlet temperature turbine (TiT) limit. Among the whole technology solutions conceived to make SI engine operating at lambda 1.0 on the whole operation map, the water injection is one of the valuable candidates. Despite the fact that the water injection has been exploited in the past, the renewed interest in it requires a deep investigation in order to outcome its potential as well as its limits.

With progressing electrification of automotive powertrains and demands to meet increasingly stringent emission regulations, a combination of an electric motor and downsized turbocharged spark-ignited engine has been recognized as a viable solution. The SI engine must be optimized, and preferentially downsized, to reduce tailpipe CO2 and other emissions. However, drives to increase BMEP (Brake Mean Effective Pressure) and compression ratio/thermal efficiency increase propensities of knocking (auto-ignition of residual unburnt charge before the propagating flame reaches it) in downsized engines. Currently, knock is mitigated by retarding the ignition timing, but this has several limitations. Another option identified in the last decade (following trials of similar technology in aircraft combustion engines) is water injection, which suppresses knocking largely by reducing local in-cylinder mixture temperatures due to its latent heat of vaporization.

The potential of 48V Mild Hybrid is promising in meeting the present and future CO2 legislations. There are various system layouts for 48V hybrid system including P0, P1, P2. In this paper, P2 architecture is used to investigate the effects of water injection benefits in a mild hybrid system. Electrification of the conventional powertrain uses the benefits of an electric drive in the low load-low speed region where the conventional SI engine is least efficient and as the load demand increases the IC Engine is used in its more efficient operating region. Engine downsizing and forced induction trend is popular in the hybrid system architecture. However, the engine efficiency is limited by combustion knocking at higher loads thus ignition retard is used to avoid knocking and fuel enrichment becomes must to operate the engine at MBT (Maximum Brake Torque) timing; in turn neutralizing the benefits of fuel savings by electrification.

Knock occurrence and fuel enrichment, which is required at high engine speed and load to limit the turbine inlet temperature, are the major obstacles to further increase performance and efficiency of down-sized turbocharged spark ignited engines. A technique that has the potential to overcome these restrictions is based on the injection of a precise amount of water within the mixture charge that can allow to achieve important benefits on knock mitigation, engine efficiency, gaseous and noise emissions. One of the main objectives of this investigation is to demonstrate that water injection (WI) could be a reliable solution to advance the spark timing and make the engine run at leaner mixture ratios with strong benefits on knock tendency and important improvement on fuel efficiency.

For reduction of fuel consumption, a new device “Water Jacket Spacer” which improves temperature distribution of a cylinder block bore wall was developed. In the case of a conventional cylinder block, coolant flow concentrates at the bottom and middle region of the water jacket. While temperature of the upper bore wall is high (due to high-temperature combustion gas) the temperature of the lower bore wall is low, since its only function is to support the piston. When the developed spacer is inserted into a water jacket, the coolant flow concentrates at the upper part of the jacket. As a result, cooling ability to the upper bore wall was improved and temperature of lower bore wall was increased, thereby reducing fuel consumption.

Most automotive piston engines employ a front-mounted, belt-driven coolant circulation pump. The pump shaft is normally supported by a double row rolling-element radial contact bearing. The engineering analysis for an improved method of water pump bearing service load and life prediction is described here. This general analysis considers most of the design variations which are found among engines, water pumps, and bearings in current use. A rather thorough accounting has been made here of the various sources of bearing loading occurring in this application. Bearing life is determined according to the recently revised A.F.B.M.A. standards.

Applying hydrodynamic lubrication theory for porous bearings and boundary lubrication theory, this paper presents a method of analyzing the performance of a water-lubricated sleeve type porous bushing in an automotive water pump design. Relations of bearing load capacity versus shaft speed have been obtained and compared for sintered iron-graphite bushings (a cermet material developed by the Ford Motor Co.), sintered iron or sintered bronze bushings, and steel bushings. The load capacity was computed, based on a minimum allowable film thickness during hydrodynamic operation, and on a maximum allowable temperature during boundary lubrication operation. The results show that sintered iron-graphite bushings are superior to sintered iron or sintered bronze bushings, as well as steel bushings, in this application, due to the lower coefficient of friction.

It has been largely announced that automotive industry is going through a disruption moment regarding applied powertrain technologies due to the efforts to decrease CO2 and pollutant gases emission, mainly through related legislations of different countries and regions. European and Asian future legislations are going to demand some electrification introduction, whether hybrid or fully electric, but even different technologies such as fuel cells and synthetic fuels over the next few years. In Brazil, with the upswing of biofuels use, considering a well to wheel CO2 emission calculation, the usage of hydrated ethanol or ethanol mixed up with gasoline in different proportions is a great solution for a continuous and progressive automotive fleet decarbonization, in parallel or associated with electrification, in a favorable pace for the market conditions.

This paper relates de development of an automotive water pump with a new production concept. During these past years, automotive components had lots of modifications on its design, function and manufacturing process. Water pumps are not include in this context, once no relevant changes were verified on design of these parts on last 30 years. By looking this scenario and the observing progress reached by engineering plastics, we decided to implement a new concept of water pump where its structural element (housing), were produced with a thermoplastic material, replacing the traditional aluminum. Note that this is not a material change because utilization of thermoplastic open possibilities of new manufacturing concepts that help to improve performance and reduce production costs. This paper relates the development process, from idea until production.

The type of pump (lobe, centrifugal, or piston) used in a circulation system determines the degree of mechanical and shear degradation inflicted upon the pigments present in a waterborne metallic paint. The visible effect of degrading the performance of a metallic paint is the extreme variation encountered in the appearance of the resulting automotive finish. We have determined through multiple angle spectrophotometry that lobe and centrifugal pumps initially cause a similar amount of degradation to the two-tone effect exhibited by a metallic finish. The degradation effect associated with a lobe pump was observed to dramatically increase with extended usage of the pump. Piston pumps were discovered to cause the least amount of paint degradation. A centrifugal pump having open impellers performed similar to a centrifugal pump with closed impellers.

The new VR220/330 series engines have been created to modernize the division's Mobile Equipment, Industrial Power Unit, and Enginator Capability through the power range from 50 to 150 BHP. The design concept which followed was to make a family of engines having a good balance between Reliability, Cost of Manufacturing, Application Ease, Serviceability, and Engine Performance. The new VR220/330 series is a refinement of an earlier VR engine family manufactured at Waukesha. Features have been developed to meet the demands of the Mobile Equipment and Industrial Engine Markets. The VR220/330 engine series has a 3.875” bore, 4.665” stroke for a displacement of 55 cu. in./cylinder. The engine family consists of 4 and 6 cylinder Gasoline, Gaseous, Diesel, and Diesel Turbocharged models. The engine family was designed to utilize some existing tooling, along with currently accepted foundry techniques, and engine technology.

This paper presents a hydraulic pump fault diagnosis method based on a discharge pressure pulsation model. This diagnosis method was based on the pressure signals measured at the discharge port of the pump. The obtained signals were transformed into frequency domain for performing wavelet analysis to separate the fault signals from the pressure signal at the time a fault occurs. This method was first evaluated via simulation analysis, and then validated against test data. Results showed that this wavelet based fault diagnosis method was capable of detecting pump failure using the outlet pressure pulsating signal.