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Delivery of a lubricant as a vapor mixed with a carrier gas provides a method of controlling the delivery rate of the lubricant. Temperatures in the range of 370 to 800 C are high enough to produce a lubricating film from tricresyl phosphate [TCP] vapor delivered in nitrogen as a carrier gas. The solid film lubricant formed by this delivery system provides excellent lubrication for a four-ball wear tester run at 370 °C. Deposit rates are compared for TCP vapor delivered lubrication over a temperature range using stainless steel and quartz surfaces. The deposit rate is sensitive to TCP concentration in the carrier gas. The deposit rates of the TCP decomposition products versus time are reported. Having been demonstrated in laboratory tests, the Vapor Phase [VP] concept is being pursued for hot section lubrication of the advanced (low heat rejection) diesel engines.

The National Research Council of Canada (NRC) has undergone the development of a Small Axial Compressor Rig for modelling altitude ice accretion in aircraft engines. The rig consists of two axial compressor stages measuring approximately 150mm in diameter, an extension duct to allow residence time for partial melting of ice crystals and a test piece. The axial compressor stages are intended to provide realistic engine conditioning such as fracture, pressure rise, temperature rise and centrifuging of glaciated ice crystals entering the rig. The rig was designed for use in altitude icing wind tunnels such as the NRC’s altitude icing wind tunnel (AIWT), research altitude test facility (RATFac.), and those of other organization such as NASA Glenn and Technical University of Braunshweig. Previous development work [1] provided partial validation of the aerodynamic performance of just the first compressor stage at 90% power.

The effectiveness of scavenging, the displacement of residual combustion gases with fresh air, is examined in an advanced, high power-density diesel engine, consisting of a two-stroke, opposed-piston reciprocator with an ultra-high boost. KIVA-3, a three-dimensional code for modeling reactive flows with fuel injection, is used to study the effect of a variety design choices on scavenging. The parametric study includes the inclined angle of the intake ports, the exhaust port timing and size and the piston stroke-to-bore ratio. A baseline geometry of the opposed-piston engine is examined in detail, which models an existing mono-cylinder test rig. The baseline-design exhibits large asymmetries, nonsteady flow and large recirculation regions that degrade the scavenging. Significant improvement in the scavenging of the baseline design is observed with a uniform inclined angle of the inlet ports of about 20° and with a larger stroke-to-bore ratio (2.0 compared with 1.08).

Selected ferritic stainless steel sheets for exhaust applications were tested under thermo-mechanical fatigue (TMF) condition in the temperature range of 400-800 °C with partial constraint. Straight welded tubes were used as the testing coupons to withstand large compression without buckling, and to understand the effect of welding as well. Repeated tests confirmed the observed failure scenario for each material type. The hysteresis loop behaviors were also simulated using the mechanism-based integrated creep and fatigue theory (ICFT) model. Although more development work is needed, for quick material screening purpose this type of testing could be a very cost effective solution for materials and tube weld development for exhaust applications.

Strain controlled thermo-mechanical fatigue (TMF) tests were conducted on a high Silicon ductile cast iron (SiMo) as the baseline material and a similar SiMo cast iron with aluminum addition (SiMoAl). The much improved fatigue life with aluminum addition is analyzed using the integrated creep-fatigue theory (ICFT) in combination with the metallurgical analysis on the tested coupons. Addition of about 3 wt.% Aluminum significantly improved TMF life of the SiMo cast iron. The results are explained by elimination of brittleness at middle temperature range, the higher flow stress, lower creep rate and higher oxidation resistance from Al addition.

One of the major sources of chlorine in automobiles is polyvinyl chloride (PVC). When old discarded automobiles enter the recycling loop by far the largest percent of this material finds its way into the solid waste fraction known as automobile shredder residue (ASR). While the majority of this waste is currently disposed of in landfills new processes are currently being evaluated to recycle and recover the valuable resources contained in this solid waste. Pyrolysis, the thermal cracking of the polymeric materials present in ASR, to recover the petrochemical hydrocarbons is one such technology which is receiving attention. However, like combustion with energy recovery, the pyrolysis process is receiving close scrutiny in terms of its environmental impact. These concerns have centered around the fate of the chlorine and the heavy metals present in the ASR.

Determining what exhaust gas recirculation (EGR) control parameters have the largest impact on engine performance and emissions is of critical importance when developing an EGR-equipped engine. These tests studied the effects of varying the net charge mass, the fresh air charge mass, the indicated power, and the oxygen equivalence ratio at various EGR fractions. The research was carried out on a direct-injection, natural gas fuelled, pilot-ignited four-stroke heavy-duty engine using Westport Innovations Inc.'s pilot-ignited, direct injection of natural gas technology. The testing was carried out using a prototype injector and the standard diesel-fuelled engine's combustion chamber. The results indicate that fuel efficiency, as well as emissions of Nitrogen Oxides (NOx) and Carbon Monoxide (CO) depend primarily on the EGR level, and not on the values of the EGR control parameters.

The use of exhaust gas recirculation (EGR) to control NOx emissions from direct-injection engines results in the reintroduction of exhaust particulate matter (PM) into the intake manifold. The influence of this recirculated PM on emissions from a pilot-ignited direct injection of natural gas engine was studied by installing a filter in the EGR system. Comparison tests at fixed engine conditions were conducted to identify differences between filtered and unfiltered EGR. No significant variations in gaseous or PM mass emissions were detected. This indicates that the recirculated PM is not contributing substantially to the increases in PM mass emissions commonly observed with EGR. Reductions in black carbon and ultra-fine particle exhaust concentrations in the exhaust were observed at the highest EGR fractions with the filter installed.

Detroit Diesel Corporation (DDC) is developing the DELTA 4.0L V6 engine, specifically for the North American light truck market. This market poses unique requirements for a diesel engine, necessitating a clean sheet engine design. DELTA was developed from a clean sheet of paper, with the first engine firing just 228 days later. The process began with a Quality Function Deployment (QFD) analysis, which prioritized the development criteria. The development process integrated a co-located, fully cross-functional team. Suppl iers were fully integrated and maintained on-site representation. The first demonstration vehicle moved under its own power 12 weeks after the first engine fired. It was demonstrated to the automotive press 18 days later. DELTA has repeatedly demonstrated its ability to disprove historical North American diesel perceptions and compete directly with gasoline engines. This paper outlines the Generation 0.0 development process and briefly defines the engine.

A study has been conducted into icephobic properties of some highly durable “off-the-shelf” elastomer materials using a rotating ice adhesion test rig installed in the NRC’s Altitude Icing Wind Tunnel. This enabled the formation of ice at environmental conditions similar to those experienced during in-flight icing encounters. Initially, the tests indicated some very positive results with ice adhesion shear stress as low as 8KPa. On further examination, however, it became apparent that the test preparation process, in which the samples were cleaned with an ethanol alcohol solution, influenced the results due to absorption and prolonged retention of the cleaning fluid. The uptake of the ethanol alcohol solution by the elastomer was found to be a function of the surface temperature and remained absorbed into the coating during the ice accretion process changing the characteristics of the coating in such a way that led to a reduction in the ice/surface bond strength.

This paper describes the equipment, analysis methods and results obtained for particle size measurements based on a particle imaging velocimetry (PIV) system in which a short duration laser pulse is used to backlight airborne particles. This produces high quality and high resolution images of fast moving airborne particles in a non-intrusive manner. This imaging technique is also used to examine particle morphology and 2D particle trajectory and velocity. The image analysis methods are outlined and validation test results discussed which show the measurement of reference glass beads between 20 and 400 microns were generally to within their stated size. As well, validation testing using known icing wind tunnel droplet distributions were compared with Spraytek 2000 Malvern droplet size measurements and showed agreement of the MVD's to be within ±5% for distributions having nominally 20, 40 and 80 micron MVD's.

Compression ignition engines, including those that use natural gas as the major fuel, produce emissions of NOx and particulate matter (PM). Westport Inc. has developed the pilot-ignited high-pressure direct-injection (HPDI) natural gas engine system. Although HPDI engines produce less soot than comparable conventional diesel engines, further reductions in engine-out soot emissions is desired. In diesel engines, multiple injections can help reduce both NOx and PM. The effect of post injections on HPDI engines was not studied previously. The present research shows that late injection of a second gas pulse can significantly reduce PM and CO from HPDI engines without significantly increasing NOx or fuel consumption. In-cylinder pressure measurements were used to characterize the heat release resulting from the multiple injections. Experiments showed that most close-coupled split injection strategies provided no significant emissions benefit and less stable operation.

Ice crystals ingested by a jet engine at high altitude can partially melt and then accrete within the compressor, potentially causing performance loss, damage and/or flameout. Several studies of this ice crystal icing (ICI) phenomenon conducted in the RATFac (Research Altitude Test Facility) altitude chamber at the National Research Council of Canada (NRCC) have shown that liquid water is required for accretion. CFD-based tools for ICI must therefore be capable of predicting particle melting due to heat transfer from the air warmed by compression and possibly also due to impact with warm surfaces. This paper describes CFD simulations of particle melting and evaporation in the RATFac icing tunnel for the former mechanism, conducted using a Lagrangian particle tracking model combined with a stochastic random walk approach to simulate turbulent dispersion. Inter-phase coupling of heat and mass transfer is achieved with the particle source-in-cell method.

The development of an optimized heat treatment schedule, with the aim of maximizing strength and relieving tensile residual stress, is important to prevent in-service cylinder distortion in Al alloy engine blocks containing cast-in gray iron liners. However, to effectively optimize the engine block heat treatment schedule, the current solutionizing parameters must be analyzed and compared to the as-cast condition to establish a baseline for residual stress relief. In this study, neutron diffraction was carried out to measure the residual stress along the aluminum cylinder bridge following solution heat treatment. The stresses were measured in the hoop, radial and axial orientations and compared to a previous measured as-cast (TSR) engine block. The results suggest that solution heat treatment using the current production parameters partially relieved tensile residual stress in the Al cylinder bridge, with stress relief being more effective near the bottom of the cylinder.

The National Research Council Canada has collected a large number of corroded and non-corroded fuselage lap joints from retired and operational aircraft. A number of these corroded joints have been disassembled in order to quantify the level of corrosion. During the disassembly, it was often observed that common repair techniques resulted in damage to the structure. The damage observed was significant enough to raise concerns regarding the effect of the repair techniques on structural integrity. This paper describes the different types of damage found.

The continued need of vehicle weight reduction provides impetus for research into the development of novel automotive casting alloys and their processing technologies. Where possible, ferrous components are being replaced by aluminum (Al) and magnesium (Mg) alloy counterparts. This transition, however, requires a systematic optimization of the alloys and their manufacturing processes to enable production of defect-free castings. In this context, prevention of hot tears remains a challenge for Al and Mg alloy thin-wall castings. Hot tears form in semi-solid alloy subjected to localized tensile stress. Classical methods of stress measurement present numerous experimental limitations. In this research, neutron diffraction (ND) was used as a novel tool to obtain stress maps of castings and to quantify the effect of two processes used to eliminate hot tears in permanent mold castings: 1) increasing of the mold temperature during casting of Mg alloys, and 2) grain refinement of Al alloys.

The recyclability of old automobiles is of major interest to auto manufacturers, original equipment manufacturers and regulatory bodies concerned about sustainable development. While the majority of the ferrous and non-ferrous metals are currently recycled, the non-metallic waste fraction generated by automobile shredding operations is currently disposed of in landfills. In view of the relatively large concentration of plastics and rubber in this material, pyrolysis, the thermal degradation of polymeric materials to predominantly hydrocarbon products, appears an ideal resource recovery option for this waste stream. In this study, the results of pyrolysis experiments performed in our laboratory will be examined and compared with pyrolysis data reported in the literature. The importance of pyrolysis temperature, pyrolysis reaction time and pyrolysis process design on product formation (liquids, solids and gases) as well as chemical composition are compared.

We have developed an original, three-dimensional icing modelling capability, called the “morphogenetic” approach, based on a discrete formulation and simulation of ice formation physics. Morphogenetic icing modelling improves on existing ice accretion models, in that it is capable of predicting simultaneous rime and glaze ice accretions and ice accretions with variable density and complex geometries. The objective of this paper is to show preliminary results of simulating complex three-dimensional features such as lobster tails and rime feathers forming on a swept wing. The results are encouraging. They show that the morphogenetic approach can predict realistically both the overall size and detailed structure of the ice accretion forming on a swept wing. Under cold ambient conditions, when drops freeze instantly upon impingement, the numerical ice structure has voids, which reduce its density.

With increasing use of boat-tails on Canadian roads, a concern had been raised regarding the possibility for ice and snow to accumulate and shed from the cavity of a boat-tail affixed to a dry-van trailer, posing a hazard for other road users. This paper describes a preliminary evaluation of the potential for ice and snow accumulation in the cavity of a boat-tail-equipped heavy-duty vehicle. A transient CFD approach was used and combined with a quasi-static particle-tracking simulation to evaluate, firstly, the tendency of various representative ice or snow particles to be entrained in the vehicle wake, and secondly, the potential of such particles to accumulate on the aft end of a dry-van trailer with and without various boat-tail configurations. Results of the particle tracking analyses showed that the greatest numbers of particles impinge on the base of the trailer for the no-boat-tail case, concentrated on the upper surface of the back face of the trailer.

Recent emission and field data from diesel particulate trap buses operating at the New York City Transit Authority (NYCTA) are summarized. As part of the NYCTA Trap Oxidizer Program, transient emission and performance test data were measured from a prototype diesel particulate trap system, which utilizes a Webasto in-line full flow diesel burner to periodically regenerate the ceramic monolith filter. In addition, the progress made during a large scale field test program of 398 new TMC RTS buses powered with Detroit Diesel Corporation (DDC) 6V-92TA bus engines equipped with Donaldson Company, Inc. (DCI) Dual Wallflow Monolith Electric Regeneration Trap System is presented. Discussion includes: trap system hardware and software issues, resulting trap system improvements, impact of the trap system on engine emissions and fuel economy, and potential trap monolith durability issues.