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A dimensionless relationship that estimates the maximum bearing load of a 4-cylinder 4-stroke in-line engine has been found. This relationship may assist the design engineer in choosing a desired counterweight mass. It has been demonstrated that: 1) the average bearing load increases with engine speed and 2) the maximum bearing load initially decreases with engine speed, reaches a minimum, then increases quickly with engine speed. This minimum refers to a transition speed at which the contribution of the inertia force overcomes the contribution of the maximum pressure force to the maximum bearing load. The transition speed increases with an increase of counterweight mass and is a function of maximum cylinder pressure and the operating parameters of the engine.

Described in this paper is a component test methodology to evaluate the door trim armrest performance in an Insurance Institute for Highway Safety (IIHS) side impact test and to predict the SID-IIs abdomen injury metrics (rib deflection, deflection rate and V*C). The test methodology consisted of a sub-assembly of two SID-IIs abdomen ribs with spine box, mounted on a linear bearing and allowed to translate in the direction of impact. The spine box with the assembly of two abdominal ribs was rigidly attached to the sliding test fixture, and is stationary at the start of the test. The door trim armrest was mounted on the impactor, which was prescribed the door velocity profile obtained from full-vehicle test. The location and orientation of the armrest relative to the dummy abdomen ribs was maintained the same as in the full-vehicle test.

Striving for sustainable transportation solutions, hydrogen is often identified as a promising energy carrier and internal combustion engines are seen as a cost effective consumer of hydrogen to facilitate the development of a large-scale hydrogen infrastructure. Driven by efficiency and emissions targets defined by the U.S. Department of Energy, a research team at Argonne National Laboratory has worked on optimizing a spark-ignited direct injection engine for hydrogen. Using direct injection improves volumetric efficiency and provides the opportunity to properly stratify the fuel-air mixture in-cylinder. Collaborative 3D-CFD and experimental efforts have focused on optimizing the mixture stratification and have demonstrated the potential for high engine efficiency with low NOx emissions. Performance of the hydrogen engine is evaluated in this paper over a speed range from 1000 to 3000 RPM and a load range from 1.7 to 14.3 bar BMEP.

Use of ethanol as gasoline replacement can contribute to the reduction of nitrogen oxide (NOx) and carbon oxide (CO) emissions. Depending on ethanol production, significant reduction of greenhouse-gas emissions is possible. Concentration of certain species, such as unburned ethanol and acetaldehyde in the engine-out emissions are known to rise when ratio of ethanol to gasoline increases in the fuel. This research explores on hydrous ethanol fueled port-fuel injection (PFI) spark ignition (SI) engine emissions that contribute to photochemical formation of ozone, or so-called ozone precursors and the precursor of peroxyacetyl nitrates (PANs). The results are compared to engine operation on gasoline. Concentration obtained by FTIR gas analyzer, and mass-specific emissions of formaldehyde (HCHO), acetaldehyde (MeCHO) and methane (CH4) under two engine speed, four load and two spark advance settings are analyzed and presented.

To address the need of increasing fuel economy requirements, automotive Original Equipment Manufacturers (OEMs) are increasing the number of turbocharged engines in their powertrain line-ups. The turbine-driven technology uses a forced induction device, which increases engine performance by increasing the density of the air charge being drawn into the cylinder. Denser air allows more fuel to be introduced into the combustion chamber, thus increasing engine performance. During the inlet air compression process, the air is heated to temperatures that can result in pre-ignition resulting and reduced engine functionality. The introduction of the charge air cooler (CAC) is therefore, necessary to extract heat created during the compression process. The present research describes the physics and develops the optimized simulation method that defines the process and gives insight into the development of CACs.

With an intention to improve the performance of reciprocating engines used for distributed generation US-Dept. of Energy has launched ARES program. Under this program, the performance targets for these natural gas-fuelled stationary engines are ≻ 50% efficiency and NOx emissions ≺ 0.1 g/bhp-hr by 2013. This paper presents two technologies developed under this program. Lean-burn operation is very popular with engine manufacturers as it offers simultaneous low-NOx emissions and high engine efficiencies, while not requiring the use of any aftertreatment devices. Though engines operating on lean-burn operation are capable of better performance, they are currently limited by the inability to sustain reliable ignition under lean conditions. Addressing such an issue, research has evaluated the use of laser ignition as an alternative to the conventional Capacitance Discharge Ignition (CDI).

The current paper describes a methodology for combustion bowl assessment for diesel engines. The methodology is based on the application of Computational Fluid Dynamics (CFD) following a Design of Experiments (DoE) procedure. In this work the 3D CFD simulation was performed by the commercial CFD code AVL-FIRE for different combustion bowls from intake valve closing (IVC) to exhaust valve opening (EVO). The initial conditions (at IVC) and boundary conditions were obtained from 1D simulation. Since the work was concentrated on the spray injection, mixing, combustion as well as bowl aerodynamics only a sector mesh was employed for the calculations. A DoE procedure was also used for this simulation work in order to minimize the number of simulation runs and at the same time maintaining the accuracy required assessing the influences of different bowl geometry, spray and intake air motion parameters.

Perception in adverse weather conditions is one of the most prominent challenges for automated driving features. The sensors used for mid-to-long range perception most impacted by weather (i.e., camera and LiDAR) are susceptible to data degradation, causing potential system failures. This research series aims to better understand sensor data degradation characteristics in real-world, dynamic environmental conditions, focusing on adverse weather. To achieve this, a dataset containing LiDAR (Velodyne VLP-16) and camera (Mako G-507) data was gathered under static scenarios using a single vehicle target to quantify the sensor detection performance. The relative position between the sensors and the target vehicle varied longitudinally and laterally. The longitudinal position was varied from 10m to 175m at 25m increments and the lateral position was adjusted by moving the sensor set angle between 0 degrees (left position), 4.5 degrees (center position), and 9 degrees (right position).

SunDiesel fuel is a biomass-to-liquid (BTL) fuel that may have certain attributes different from conventional diesel. In this investigation, 100% SunDiesel was tested both in a Mercedes A-Class (MY1999) diesel vehicle and a single-cylinder heavy-duty compression-ignition direct-injection engine. The SunDiesel's emissions and fuel consumption were significantly better than conventional diesel fuel, especially in nitrogen oxides (NOx) reduction. In the vehicle U.S. Environmental Protection Agency (EPA), Federal Test Procedure 75 (FTP-75), and New European Drive Cycle (NEDC) tests, the carbon dioxide emissions on a mile basis (g/mile) from SunDiesel fuel were almost 10% lower than the conventional diesel fuel. Similarly, in the single-cylinder engine steady-state tests, the reductions in brake specific NOx, carbon monoxide (CO), and particulate matter (PM) are equally significant. Combustion analysis, though not conclusive, indicates that there are differences deserving further research.

With the increasing demand for Battery Electric Vehicles (BEVs) capable of extended mileage, optimizing their efficiency has become paramount for manufacturers. However, the challenge lies in balancing the need for climate control within the cabin and precise thermal regulation of the battery, which can significantly reduce a vehicle's driving range, often leading to energy consumption exceeding 50% under severe weather conditions. To address these critical concerns, this study embarks on a comprehensive exploration of the impact of weather conditions on energy consumption and range for the 2019 Nissan Leaf Plus. The primary objective of this research is to enhance the understanding of thermal management for BEVs by introducing a sophisticated thermal management system model, along with detailed thermal models for both the battery and the cabin.

The Center for Transportation Research (CTR) Vehicle Systems team modified a Nissan CK-2 Continuously Variable Transmission (CVT) for a diesel hybrid powertrain application. Mechanical and electrical modifications were made to the CVT, both internal and external to the transmission. The goal of this experiment was to investigate and demonstrate the potential of CVT for diesel engines hybrid electric vehicles (HEVs) in fuel economy and emissions. The test set-up consisted of a diesel engine coupled to an electric motor driving a Continuously Variable Transmission (CVT). This hybrid drive is connected to a dynamometer and a DC electrical power source creating a vehicle context by combining advanced computer models and emulation techniques. The experiment focuses on the impact particular transmission control strategies have on measured fuel economy and emissions specifically, nitrogen oxides (NOx) and particulate matter (PM).

Low temperature combustion through in-cylinder blending of fuels with different reactivity offers the potential to improve engine efficiency while yielding low engine-out NOx and soot emissions. A Navistar MaxxForce 13 heavy-duty compression ignition engine was modified to run with two separate fuel systems, aiming to utilize fuel reactivity to demonstrate a technical path towards high engine efficiency. The dual-fuel engine has a geometric compression ratio of 14 and uses sequential, multi-port-injection of a low reactivity fuel in combination with in-cylinder direct injection of diesel. Through control of in-cylinder charge reactivity and reactivity stratification, the engine combustion process can be tailored towards high efficiency and low engine-out emissions. Engine testing was conducted at 1200 rpm over a load sweep.

A multiple-injection combustion strategy has been developed for heated gasoline direct injection compression ignition (HGCI). Gasoline was injected into a 0.4L single cylinder engine at a fuel pressure of 300bar. Fuel temperature was increased from 25degC to a temperature of 280degC by means of electric injector heater. This approach has the potential of improving fuel efficiency, reducing harmful CO and UHC as well as particulate emissions, and reducing pressure rise rates. Moreover, the approach has the potential of reducing fuel system cost compared to high pressure (>500bar) gasoline direct injection fuel systems available in the market for GDI SI engines that are used to reduce particulate matter. In this study, a multiple injection strategy was developed using electric heating of the fuel prior to direct fuel injection at engine speed of 1500rpm and load of 12.3bar IMEP.

The objective of this paper is to present the results of diesel exhaust aftertreatment testing and analysis done under the FreedomCAR program. Nitrogen Oxides (NOx) adsorber technology was selected based on a previous investigation of various NOx aftertreatment technologies including non-thermal plasma, NOx adsorber and active lean NOx. Particulate Matter (PM) emissions were addressed by developing a catalyzed particulate filter. After various iterations of the catalyst formulation, the aftertreatment components were integrated and optimized for a light duty vehicle application. This compact exhaust aftertreatment system is dual leg and consists of a sulfur trap, NOx adsorbers, and catalyzed particulate filters (CPF). During regeneration, supplementary ARCO ECD low-sulfur diesel fuel is injected upstream of the adsorber and CPF in the exhaust. Steady state and transient emission test results with and without the exhaust aftertreatment system (EAS) are presented.

The superior fuel economy of direct injection internal combustion engines (diesel and gasoline) is related to use of a high compression ratio to auto-ignite the fuel and the overall lean combustible mixture. Two of the major problems in diesel engine emissions are the NOx and soot emissions, which are caused by the heterogeneity of the charge and the properties of the diesel fuel. Conventional Direct Injection Spark Ignition Gasoline engines don't have these problems because of the fuel properties particularly its volatility. However, its efficiency and specific power output are limited by the knock, knock produced preignition and the sporadic preignition phenomenon. The Gasoline Direct Injection Compression Ignition (GDICI) engine combines the superior features of the two engines by increasing the compression ratio and use of gasoline as a fuel.

The potential exists to displace a portion of the petroleum diesel demand with butanol and positively impact engine-out particulate matter. As a preliminary investigation, 20% and 40% by volume blends of butanol with ultra low sulfur diesel fuel were operated in a 1999 Mercedes Benz C220 turbo diesel vehicle (Euro III compliant). Cold and hot start urban as well as highway drive cycle tests were performed for the two blends of butanol and compared to diesel fuel. In addition, 35 MPH and 55 MPH steady-state tests were conducted under varying road loads for the two fuel blends. Exhaust gas emissions, fuel consumption, and intake and exhaust temperatures were acquired for each test condition. Filter smoke numbers were also acquired during the steady-state tests. The results showed that for the urban drive cycle, both total hydrocarbon (THC) and carbon monoxide (CO) emissions increased as larger quantities of butanol were added to the diesel fuel.

The performance of the Common Rail diesel injection system (CRS) is investigated experimentally in a single cylinder engine and a test rig to determine the cycle-to-cycle variation in the injection pressure and its effects on the needle opening and rate of fuel delivery. The engine used is a single cylinder, simulated-turbocharged diesel engine. Data for the different injection and performance parameters are collected under steady state conditions for 35 consecutive cycles. Furthermore, a mathematical model has been developed to calculate the instantaneous fuel delivery rate at various injection pressures. The experimental results supported with the model computations indicated the presence of cycle-to-cycle variations in the fuel injection pressure and needle lift. The variations in the peak-cylinder gas pressure, rate of heat release, cylinder gas temperature and IMEP are correlated with the variation in the injection rate.

The effects of different blends of Soybean Methyl Ester (biodiesel) and ultra low sulfur diesel (ULSD) fuel: B-00 (ULSD), B-20, B-40, B-60, B-80 and B-100 (biodiesel); on autoignition, combustion, performance, and engine out emissions of different species including particulate matter (PM) in the exhaust, were investigated in a single-cylinder, high speed direct injection (HSDI) diesel engine equipped with a common rail injection system. The engine was operated at 1500 rpm under simulated turbocharged conditions at 5 bar IMEP load with varied injection pressures at a medium swirl of 3.77 w ithout EGR. Analysis of test results was done to determine the role of biodiesel percentage in the fuel blend on the basic thermodynamic and combustion processes under fuel injection pressures ranging from 600 bar to 1200 bar.

This report describes work recently performed by AVL and DaimlerChrysler, including both simulations and single-cylinder research engine development, to quantify the effects of fuel humidity on the performance of an internal combustion engine fueled by hydrogen. The combustion process was simulated from both a thermodynamic and a chemical kinetics standpoint. Both simulations suggested that substantial NOx reductions could be achieved. An engine was then operated on a laboratory fuel system designed to provide hydrogen at various levels of humidity, and the sensitivity of its performance (emissions and efficiency) to humidity and excess air ratio was determined. These tests verified that NOx emissions were reduced by fuel humidity. Finally, the engine and simulation results were compared. Although correlation was not perfect, the trends proved to be correct.

The purpose of this study was to determine the effect of injector nozzle hole size, shape, and finish on performance and emissions in a light-duty diesel engine. Two sets of six-hole valve covered orifice (VCO) nozzles were tested with nearly identical volumetric flow rates but varying geometry and finish. The 17% hydro-erosion (HE) nozzles had a 22% larger discharge coefficient (CD), compared to the 7% HE nozzles. In order to maintain similar volumetric flow rates, the orifice diameter of the 17% HE nozzles were reduced by almost 10%.The nozzles were tested in a 1.7L, four-cylinder, common rail diesel engine, operating on conventional D2 diesel fuel. The 17% HE, conical-shaped nozzles reduced fuel specific particulate matter (PM) and increased fuel specific oxides of nitrogen (NOx) emissions, over the 7% HE, straight-shaped nozzle.