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In many areas, neural network technology has made a successful transition from theory to practical application, primarily due to the advances that have been made in computer technology and digital signal processing. Research at the University of Saskatchewan over the past few years has focused on applying neural network technology to fluid power systems. This paper will examine four projects that have been initiated by the authors and their graduate students which use neural networks for purposes of open loop pattern following, multiple input - multiple output control, indirect measurement of actuator displacement, and hydraulic component identification. A brief introduction to static and dynamic neural networks is given. Descriptions of the individual project objectives, the experimental implementation of neural networks to achieve these objectives, and some typical experimental results are considered.

This bench test for lubricity of diesel fuels employs a crossed-axis roller on cylinder geometry. The roller on cylinder lubricity evaluator (ROCLE) yields a dimensionless lubricity number (LN) based on the ratio of wear area stress to Hertzian contact stress, all divided by the stable coefficient of friction. Fuels yielding LN's greater than 1.0 are judged satisfactory. A range of lubricity numbers from 0.5 for kerosene to 1.7 for canola vegetable oil provides good tribological discrimination between various fluids. The addition of 2% canola methyl ester to low sulfur No.1 diesel produces equivalent lubricity to No.2 high sulfur diesel fuel.

In much heavy industrial equipment, power transfer is primarily provided by a hydraulic system. Reliable operation of a hydraulic circuit can only be ensured through proper design, effective maintenance and continuous monitoring. Each of these areas requires the expertise of well-trained and experienced individuals. Unfortunately such individuals are not always available. However, the recently introduced technology of “expert” or “knowledge-based” systems can make these individuals' expertise available in the form of a computer program. As part of a long term project in the application of expert systems to hydraulic circuit design, a prototype program has been developed which can successfully configure a variety of circuits including multiple load and add-on circuits. This is currently being expanded to include sequenced circuits, steady-state circuit analysis, which would include component sizing, and dynamic analysis.

This paper presents the experimental verification of a new type of fuel-air ratio controller for spark ignition (SI) engines. The controller does not require any initial calibration before its first use on a new engine beyond some very general information which is used to generate an initial fuel map. The controller then continually updates this nonlinear fuel map in response to changes in the engine or fuel while driving. The controller was implemented on a 2003 Vortec 6L V8 engine in a General Motors 2500HD truck with an OEM (original equipment manufacturer) natural gas conversion. Preliminary results indicate the controller behaves in a manner comparable to OEM controllers in terms of drivability and exhaust emissions, at potentially a much lower development cost.

Most fertilizer application systems are not capable of variable rate adjustments “on-the-fly”. To change the application rate, the farmer must dismount the tractor and change the gear ratio mechanically (i.e. via gears, chains, etc.). Air seeder manufacturers have come up with their own unique solutions to address this problem, usually involving electrohydraulics. At present there are older seeding units that perform adequately, but do not have the variable rate option. A retrofit is therefore very desirable for these units. In this paper, the feasibility of a simple hydraulic proportional valve and variable speed motor circuit is employed to replace the gears and chains. The unit is integrated with a microcontroller to provide compensation to the nonlinear properties of a proportional valve, and in turn provide a very accurate feedrate. In addition, direct user input from the cab of the tractor is possible, allowing on-the-go rate changes.

Eco-efficient and cost effective natural fibre - thermoplastic composites have gained attention to a great extent in the automotive industry. Most of the OEM specifications for automotive interior parts, for example, instrument panels, recommend the composite should have a minimum flexural modulus of 1900 MPa, a notched Impact strength greater than 150 J/m at room temperature and a melt flow index of 5 g/10min and above [1, 2 and 3]. The objective of this work was to develop a high performance hybrid composite by injection molding process of the composites made from natural fibre in combination with glass fibre or calcium carbonate in a thermoplastic matrix to meet the specifications required for automotive interior parts applications. Mechanical properties, such as tensile and flexural strengths and moduli of the composites prepared, were found to be highly promising.

This paper describes the design of an intelligent control strategy that would allow the conversion of a gasoline engine to a bi-fuel form with minimal alteration. Conversion of a conventional gasoline engine to a bi-fuel form is easy and can be achieved at a relatively low cost. By using a bi-fuel engine in vehicles, the advantages of both natural gas and gasoline can be exploited. When the natural gas tank empties, the vehicle can be operated on gasoline until it is refueled with natural gas. This paper describes an add-on control module that is developed and applied to an engine for bi-fuel operation. The control scheme uses neural networks and is capable of substantially improving the operation of a bi-fuel engine in terms of emissions. Simulation results are reported.

In this study, a simulation-based flow optimization of the diesel particulate filter (DPF) system is performed. The geometry and the swirl component of the inlet flow is optimized to improve flow uniformity upstream of the filter and to decrease overall pressure drop. The flow through the system is simulated with Fluent computational fluid dynamics (CFD) software from Fluent Inc. The wall-flow filter is modeled with an equivalent porous material. This study only investigates the clean flow. The DPF system is composed of three parts: the inlet diffuser, the filter and the outlet nozzle. In the original system a linear cone joins the inlet and outlet pipes to the cylindrical filter. Due to the large opening angle of this cone, flow separates and creates a recirculation zone between the inlet and the filter. The flow pattern reveals that a large area of the filter is not used: More than 88% of the air flow passes through less that 53% of the area.

A comparison of scanning mobility particle sizer (SMPS) and laser-induced incandescence (LII) measurements of diesel particulate matter (PM) was performed. The results reveal the significance of the aggregate nature of diesel PM on interpretation of size and volume fraction measurements obtained with an SMPS, and the accuracy of primary particle size measurements by LII. Volume fraction calculations based on the mobility diameter measured by the SMPS substantially over-predict the space-filling volume fraction of the PM. Correction algorithms for the SMPS measurements, to account for the fractal nature of the aggregate morphology, result in a substantial reduction in the reported volume. The behavior of the particulate volume fraction, mean and standard deviation of the mobility diameter, and primary particle size are studied as a function of the EGR for a range of steady-state engine speeds and loads for a turbocharged direct-injection diesel engine.

It is not uncommon for complex engineering products to undergo several design iterations due to changing market expectations or inadequate performance. In such circumstances, a prototype is generally available that could be used for performance analysis before a revision to the design is made. The availability of a prototype can be an invaluable tool for the analysis of the impact of potential design changes on the system performance. In this paper, a process is proposed for the derivation of a physical model that could be used for design analysis. The process uses model identification for determination of model complexity and numerical optimization for estimation of model parameters. This process is applied to a new pneumatic fan clutch system that has been developed to improve the efficiency of engine temperature regulation in heavy-duty commercial vehicles. This system is currently in a prototype phase and its detailed physical model is required for design trade-off analysis

Until recently, the aerodynamic design of large transport trucks has often ignored an important contribution to drag caused by the accessory rearview mirrors. In this study, three commercially available truck mirrors are tested full-scale in a wind tunnel at highway speeds. The actual drag forces and the coefficients of drag based on frontal and glass areas are compared for various mirror angles, with and without a convex-mirror attachment. All three mirror types produced significantly high drag forces which were used to estimate the fuel consumption attributed to mirror aerodynamic resistance. A standard rearview mirror, with mounting brackets, set was found to exhibit a drag coefficient, based on the glass area, of 1.81, which would increase the drag of a typical (Cd = 0.7, Af = 4.5m2) truck by about 8.5 percent.

The laminar burning speed is an important intrinsic property of an air-fuel mixture determining key combustion characteristics such as turbulent flame propagation. It is a function of the mixture composition (mixture fraction and residual gas mass fraction) and of the thermodynamic conditions. Experimental measurements of Laminar Flame Speeds (LFS) are common in literature, but initial pressure and temperature are limited to low values due to the test conditions: typical pressure values for LFS detection are lower than 25 bar, and temperature rarely exceeds 550 K. Actual trends in spark ignition engines are to increase specific power output by downsizing and supercharging, thus the flame front involves even more higher pressure and temperature since the beginning of combustion.

This study investigates the life cycle greenhouse gas (GHG) emissions of a set of vehicles using two real-world gliders (vehicles without powertrains or batteries); a steel-intensive 2013 Ford Fusion glider and a multi material lightweight vehicle (MMLV) glider that utilizes significantly more aluminum and carbon fiber. These gliders are used to develop lightweight and conventional models of internal combustion engine vehicles (ICV), hybrid electric vehicles (HEV), and battery electric vehicles (BEV). Our results show that the MMLV glider can reduce life cycle GHG emissions despite its use of lightweight materials, which can be carbon intensive to produce, because the glider enables a decrease in fuel (production and use) cycle emissions. However, the fuel savings, and thus life cycle GHG emission reductions, differ substantially depending on powertrain type. Compared to ICVs, the high efficiency of HEVs decreases the potential fuel savings.

Large-scale emergency or off-grid power generation is typically achieved through diesel or natural gas generators. To meet governmental emission requirements, emission control systems (ECS) are required. In operation, effective control over the generator’s acoustic emission is also necessary, and can be accomplished within the ECS system. Plug flow mufflers are commonly used, as they provide a sufficient level of noise attenuation in a compact structure. The key design parameter is the transmission loss of the muffler, as this dictates the level of attenuation at a given frequency. This work implements an analytically decoupled solution, using multiple perforate impedance models, through the transfer matrix method (TMM) to predict the transmission loss based on the muffler geometry. An equivalent finite element model is implemented for numerical simulation. The analytical results and numerical results are then evaluated against experimental data from literature.

The manufacturing tolerances of off-highway machine linkages have an impact on linkage position during machine use. A study was undertaken to determine the extent of these tolerances on linkage position for standard machining tolerances of each linkage pin joint for a four wheel drive loader linkage. Linkage positions and distributions for each pin joint are shown in order to determine positional accuracy of the working tool connected to the linkage and impact to the machine loads. It is determined that the affect of the machining tolerances on this linkage have a very minor impact on the linkage position when the linkage is in new condition (before use) and the maximum variation in linkage actuation loads is less than 1% of nominal load.

The present paper aims at developing an innovative procedure to create a one-dimensional (1D) real-time capable simulation model for a heavy-duty diesel engine. The novelty of this approach is the use of the top-level engine configuration, test cell measurement data, and manufacturer maps as opposite to common practice of utilizing a detailed 1D engine model. The objective is to facilitate effective model adjustments and hence further increase the application of Hardware-in-the-Loop (HiL) simulations in powertrain development. This work describes the development of Fast Running Model (FRM) in GT-SUITE simulation software. The cylinder and gas-path modeling and calibration are described in detail. The results for engine performance and exhaust emissions produced satisfactory agreement with both steady-state and transient experimental data.

In order to meet emissions and power requirements, modern engine design has evolved in complexity and control. The cost and time restraints of calibration and testing of various control strategies have made virtual testing environments increasingly popular. Using Hardware-in-the-Loop (HiL), Volvo Penta has built a virtual test rig named VIRTEC for efficient engine testing, using a model simulating a fully instrumented engine. This paper presents an innovative Artificial Neural Network (ANN) based model for engine simulations in HiL environment. The engine model, herein called Artificial Neural Network Engine (ANN-E), was built for D8-600 hp Volvo Penta engine, and directly implemented in the VIRTEC system. ANN-E uses a combination of feedforward and recursive ANNs, processing 7 actuator signals from the engine management system (EMS) to provide 30 output signals.

TPO is being used to make automotive parts for its number of advantages: i) low temperature flexibility and ductility, ii) excellent impact/stiffness/flow balance, iii) excellent weatherability, and iv) free-flowing pellet form for easy processing, storage, and handling. However, by foaming TPO, due to its higher rigidity-to-weigh ratio, it would offer additional advantages over the solid counterparts in terms of reduced weight, reduced material cost, and decreased fuel usage without compromising their performance. Since a major component in TPO is polypropylene (PP), understanding PP foaming behaviours is an important step towards understanding TPO foaming. For foam materials, cell density and cell size are two significant parameters that affect their material properties. In this research, we observed the cell nucleation and initial growth behaviours of PP foams blown with CO2 under various experimental conditions in a batch foaming simulation system.

Particulate matter emissions from gasoline direct injection engines are a concern due to the health effects associated with ultrafine particles. This experimental study investigated sources of particulate matter emissions variability observed in previous tests and also examined the effect of ethanol content in gasoline on particle number (PN) concentrations and particle mass (PM) emissions. FTIR measurements of gas phase hydrocarbon emissions provided evidence that changes in fuel composition were responsible for the variability. Exhaust emissions of toluene and ethanol correlated positively with emitted PN concentrations, while emissions of isobutylene correlated negatively. Exhaust emissions of toluene and isobutylene were interpreted as markers of gasoline aromatic content and gasoline volatility respectively.

The increasing use of natural gas as a vehicle fuel has generated considerable research activity to characterize the performance and emissions of engines utilizing this fuel. However, virtually all of the results reported have been for pushrod OHV spark ignition engines or SI conversions of heavy-duty diesel engines. Because of the pressure to improve fuel economy imposed by CAFE requirements, passenger cars are increasingly tending toward high specific output, small displacement engines. These engines employ such features as four valves per cylinder and centrally located spark plugs which give them a different dependence on operating variables than traditional pushrod OHV engines. In this study, experiments were carried out with a two-liter four-cylinder Nissan SR20DE engine representative of modern design practice. The engine was operated on gasoline and natural gas at six different loads and three different speeds. Some tests were also done with isooctane.