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The 9-meter wind tunnel of the National Research Council (NRC) of Canada is commonly employed in full-scale testing of class 8 tractors. In this configuration the model blocks 10 - 15% of the test section cross-sectional area, which is greater than generally advocated blockage limits. The NRC utilizes the Maskell III method to correct data for wall interference but the effectiveness of this technique at such blockage levels remained to be seen. Corrected full-scale data was compared to data acquired with a half-scale model to determine how closely the corrected high-blockage data would agree with the low-blockage baseline. The half-scale model presented an opportunity to test at full-scale Reynolds numbers, with less than 4% blockage, which falls within most recommendations of maximum allowable blockage.

The Gas Turbine Laboratory of the National Research Council of Canada (NRC) has been involved in icing certification testing of gas turbine engines for over 60 years. It has become evident from flight incident reports in recent years, that ice crystals can have serious effects on the performance of the core of a gas turbine. This has led to the proposal of a new certification requirement for turbofan engines. This paper describes the test facilities and procedures, as well as the analysis and verification methods, which have been used recently to develop a new ice crystal generating system. The paper describes the ice crystal production and delivery systems, as well as the design and development version for business jet sized engines. In addition, a description of some component testing using ice crystals on a heated flat plate is included to demonstrate that the facility can replicate rapid ice crystal build-up on surfaces which are significantly above the melting point.

Nowadays application of light alloys like aluminium in automobile industry has found a striking role. Higher strength over weight ratio which causes lower fuel consumption seems to be the first reason. Also some other reasons like ease of manufacturing, protection against corrosion and ease of recycling are other motivations for car designers to use various aluminium alloys as much as possible. Due to lack of variable thickness tubes, they have not found a lot of applications in the car component design. This paper aims to introduce these types of tubes to automotive industry. Also these tubes are one of the essential elements in the complementary processes like tube hydroforming and cause ease of production and decreasing risk of scrap in manufacturing cycles.

Tube drawing is a well known process involving at room temperature the reduction of diameter and wall thickness to obtain specified values. The initial tube is drawn into a die of a smaller opening and its thickness achieved by use of a mandrel. Usually, the mandrel has a land area which diameter defines by sizing the inside diameter of the final tube. Some structural components found in cars, aircrafts and other vehicles require bent or hydroformed tubes of lower weight. It is of interest to have tubes of varying axial or circumferential thickness so that to reduce overweight in low stressed areas and reinforce it otherwise. However, the production of tubes of varying thickness is more difficult in reason notably of higher metal flow stresses in the deformation zone and the need to control precisely the mandrel position during drawing.

The aerodynamic effects of the pickup truck tailgate are examined in this paper. It is shown that the removal or the lowering of the tailgate increases the aerodynamic drag of a pickup truck, increases lift by up to sixty percent and increases the yawing moment. All these changes are negative and reduce vehicle performance, albeit, only by small amounts. This finding demonstrates that the commonly seen removal of tailgates to reduce aerodynamic drag is a public misconception that should be discouraged by manufacturers and by regulators.

Determining the fundamental role of gravity in vital biological systems in space is one of six science and research areas that provides the philosophical underpinning for why NASA exists. The study of cells, tissues, and microorganisms in a spaceflight environment holds the promise of answering multiple intriguing questions about how gravity affects living systems. To enable these studies, specimens must be maintained in an environment similar to that used in a laboratory. Cell culture studies under normal laboratory conditions involve maintaining a highly specialized environment with the necessary temperature, humidity control, nutrient, and gas exchange conditions. These same cell life support conditions must be provided by the International Space Station (ISS) Cell Culture Unit (CCU) in the unique environment of space. The CCU is a perfusion-based system that must function in microgravity, at unit gravity (1g) on earth, and from 0.1g up to 2g aboard the ISS centrifuge rotor.

Neutral buoyancy (NB) and parabolic flight (PF) are the only available human-scale three-dimensional spaceflight simulation environments. As such, both environments are used extensively for both research and mission operations purposes despite a lack of quantitative (or even qualitative) characterization of the fidelity of either environment to the spacelfight analog. The present study was undertaken as part of a larger research effort to begin to build such characterizations. Eight healthy adults (4 men and 4 women) were asked to adopt relaxed postures while ‘standing’ in space shuttle middeck standard-type foot restraints, in NB and during the 0g periods of PF. Subjects were tested in NB in 9 orientations, 3 trials each: Upright; tilted 45° Front, 45° Back, 45° Right, 45° Left; and tilted 90° Front, Back, Right, and Left. PF limitations prohibited 90° testing; consequently the PF test protocol included only Upright and 45° orientations.

A dynamic systems modelling approach is examined for its suitability for assessing sustainable performance in technological innovation. A computer model of the energy needs in the Canadian road transportation sector was developed to study the sustainable performance of bio-ethanol. It considers the potential increase in the consumption of energy as the economy expands in the next 25 years, taking into account demographic trends, consumer choices, and technological advances. While the primary environmental measure tracked is focused on greenhouse gas emissions with respect to the Kyoto target, it also includes considerations for land use and farming practices, and distinguishes between fossil and bio-carbon emissions. As well, it allows for different sources of biomass, including crop byproducts and dedicated crops. Various scenarios for bio-ethanol to penetrate the consumer market were set up to investigate a range of future evolution paths.

An experimental test of a non-contact method for determining simultaneously the pressure in each cylinder of a reciprocating engine is reported. The method exploits a pattern recognition technique to compare crankshaft speed fluctuations to reference patterns in a knowledge base. The crankshaft speed is measured by timing the passage of gear teeth on the engine's flywheel. The experiment was carried out on a Detroit Diesel Corporation 6V-92TA engine. The baseline operating condition was 75 percent rated load at 1200 rpm. The engine's six cylinders were individually under-fuelled from the baseline operating condition to achieve peak pressure reductions of 5 to 20 percent. The required reference angular velocity waveforms were obtained by measuring the effect of under-fuelling individual cylinders to reduce their peak pressures by 10 percent. The experimental results show that the method evaluates the cylinder pressures with an RMS error of less than 6 percent.

This paper examines the aerodynamic behaviour of plane-walled, single-plane-expansion, underbody diffusers fitted to a wind-tunnel model of a wheel-less, simple body having automobile proportions. The measurements were performed over a moving-belt assembly in the Pilot Wind Tunnel of the National Research Council of Canada (NRC). The purposes of the investigation were: to understand the governing physics of automotive underbody diffusers operating in ground proximity, to examine the effect of moving-ground and fixed-ground simulations on the behaviour of such diffusers and on the corresponding vehicle downforce and drag, to map the performance of simple, quasi-two-dimensional diffusers when used to produce downforce or drag reduction.

Three fuels with cetane numbers of 45, 36 and 29 have been run at four load levels at each of three speeds in a Detroit: Diesel 3–71 engine with standard injectors. Measurements of temperatures, pressures, Load, fuel flow, cylinder pressure in one cylinder, strain gauge measurements from the rocker arm operating one injector and exhaust emissions were all recorded. Comparisons show little change in operation except for increases in ignition delay and rate of cylinder pressure rise with the low cetane fuels. It was concluded, on the basis of these short runs, that the intermediate fuel probably would not cause major difficulties but the lowest cetane fuel could possibly present problems with noise and engine durability.

The present day measure of the ignition quality of a diesel fuel is the cetane number. Cetane number determination is carried out using a special single cylinder engine with reproducible operating conditions and variable compression ratio. The importance of the carbon skeletal structure of the fuel on the ignition quality is qualitatively well known, but the practice of defining the ignition quality of diesel fuels by a term, whose physical and/or chemical meaning is not well understood, has not been abandoned yet. The correlations that have been proposed recently, which relate the total fuel aromaticity or mid-boiling point, hydrogen content and density to the cetane number, suffer from the lack of representation of the fuel's compositional structure, and of well defined relationship, if any, between boiling point, hydrogen content, density and ignition quality.

The usage of aviation turbine fuel in Canadian operations has been the subject of a study sponsored by the Canadian Ministry of Transport. The study was designed to cover all aspects of aircraft operation from ground handling to aircraft in flight and included such parameters as availability and operating costs. Of particular importance was the effect of Canadian climatic conditions on the requirements for aviation turbine fuels for Northern operations. The final report prepared by an engineering consultant was based upon the reports from four sub-groups formed to cover all the aforementioned areas. The final conclusions of the study presented in this paper consider that due to the climatic conditions there is a place for both wide-cut and kerosene fuels in Canadian operations.

Six experimental fuels representative of Canadian future fuel options were tested against a reference fuel in a Bombardier 12 cylinder, 4 stroke, 3000 hp, medium speed diesel. The reference fuel was a straight run ASTM #2-D. The first test fuel blend consisted of heavy atmospheric gas oil that extended the distillation range (higher end point) of the other blend component ASTM #2-D. The second fuel was a blend of a distillate cut from a mixture of conventional and tar sands crude with hydrogen treated cracked stock. This provided a fuel with substantial levels of aromatic and cracked components. The third fuel was gas oil side stream: a low cetane number, high aromatics level tar sands distillate. The fourth fuel was an equal portion blend of tar sands crude components, gas oil side-stream and heavy unifined gas oil. The fifth fuel was a blend of ASTM #2-D heating oil and a substantial portion of stabilized cracked stock.

A critical evaluation of the current ASTM method of rating diesel fuels, and of the available non-engine techniques for the estimation of cetane nunbers of diesel fuels is presented. The relationship between ignition quality and fuel composition is reviewed and it is shown that each member of an homologous series of hydrocarbons does not have the same ignition characteristics as the other members of the series. It is emphasized that the belief that paraffins have relatively high cetane ratings as compared to aromatics and cycloparaffins is not always correct. The basic flaw in the cetane index correlations, which use the easily measurable physical properties of the fuels as independent parameters, is explained. A fuel data base has been used to compare the different correlations.

Four experimental diesel fuels with cetane numbers (CN) of 40, 37, 35 and 27 have been tested in a Detroit Diesel Allison 3-71 engine using the standard N65 injectors. The 35 CN fuel was a blend of distillates from conventional and tar sands crude with hydrogen treated cat-cracked stock. This provided a fuel typical of the 1990's and beyond, with substantial levels of aromatic and cracked components. The 27 CN fuel was a blend of the same components as the 35 CN fuel only with a larger portion of the hydrogen treated cat-cracked component. The 40 CN fuel was identical to the 35 CN fuel with a .2% DII-3 Diesel Ignition Improver. The 37 CN fuel was a blend of Canadian winter diesel fuel oil and 24% Light Cycle Oil (LCO), The four experimental fuels and one reference fuel were tested at four load levels at each of three engine speeds. The performance and combustion characteristics were compared with the physical and chemical fuel properties.

Two Canadian tar sands derived experimental diesel fuels with cetane numbers of 26 and 36 and a reference fuel with a cetane number of 47 were tested in a Deutz (F1L511D), single cylinder, A stroke, naturally aspirated research engine. The fuels were tested at intake and cooling air temperatures of 30 and 0°C. The 36 cetane number fuel was tested with advanced, rated and retarded injection timings. Poor engine speed stability at light loads and excessive rates of combustion pressure rise were experienced with the lowest cetane number fuel. Detailed performance/combustion behavior is presented and a correlation with fuel structural composition is made. The analytical techniques used to characterize the fuels included liquid chromatography, gas chromatography mass spectrometry (GC-MS) and proton nuclear magnetic resonance spectrometry (PNMR).

A simplified mathematical solution to predict transient off tracking of multiple vehicle combinations is presented. The generalized equations assume a constant radius curve of any angular duration with a tangent lead in and run out. The validated solution yields the off tracking of a vehicle or vehicle combination with respect to a track mounted observer. The equations are of continuous piecewise form and are field solvable.

This paper outlines the techniques used to install both a full scale and a half scale tractor-trailer model in the 9×9 meter National Research Council of Canada wind tunnel in Ottawa, Canada. The objectives were to measure the cooling drag of an active cooling system and to investigate the aerodynamic testing limits of long, yawed models inside a solid wall wind tunnel. The tunnel interference problem is discussed as it pertains to the upstream boundary, test section floor, downstream boundary, ceiling and side walls and tractor-trailer surface pressure measurements. A potential solution to the problem, however, is the subject of a follow-up paper.

The Enhanced/Synthetic Vision System (E/SVS) is a Technology Demonstrator (TD) project supported by the Chief, Research and Development of the Canadian Department of National Defence. E/SVS displays an augmented visual scene to the pilot that includes three separate image sources: a synthetic computer - generated terrain image; an enhanced visual image from an electro-optical sensor (fused as an inset); and aircraft instrument symbology, all displayed to the pilot on a Helmet Mounted Display (HMD). The synthetic component of the system provides a 40 degree vertical by 80 degree horizontal image of terrain and local features. The enhanced component digitizes imagery from electro-optic sensors and fuses the sensor image as an inset (20 degrees by 25 degrees) within the synthetic image. Symbology can be overlaid in any location within the synthetic field-of-view and may be head, aircraft, target or terrain referenced.