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The viscosity change of multigrade motor oils in service has been evaluated in a fleet representative of the present European car population. The evaluation covered air- and water-cooled engines, with conventional and integral gearboxes, and displacements ranging from 500-1750 cc. The effect of car, service, average ambient temperature, and type of polymer on the viscosity change of a lubricant has been estimated. The multigrade test oils have also been run in injector and bench engine tests in order to compare field testing results with laboratory techniques being developed.

The exhaust emissions from a single-cylinder spark ignition engine were measured as a function of burning time. Flame propagation time was measured with an ionization probe, and the exhaust gas was sampled with a gas sampling valve. Electronic control logic determined the cycles to be sampled, based on the flame propagation time. Tests were carried out at full throttle, for lean, optimum, and rich A/F. The exhaust components measured were CO, HC, O2, H2, and N2 using a gas chromatograph. The emission most affected by CBCV is CO. Cycles that are either faster or slower than the mean cycle have increased CO, particularly at lean A/F where a five-fold difference in CO concentration was measured. HC emissions show a 150% change for the same conditions. For other than lean A/F operation, H2 was an exhaust product, up to 6% at rich A/F operation. It is well established that reductions in CBCV would improve efficiency and power output.

CEC investigation group IGL-8 has conducted a survey of European engine cold starting and oil viscosity requirements. The group's objectives were to determine if the 20W bracket was too wide for European use and what alternatives existed for improving the matching of oil quality to manufacturer needs. A study of engine cranking speeds showed that the span of the 20W range is twice that of the 10W range for European cars. Car Cold Startability, and weather data analysis, also showed that the span covered by the 20W range was double that for the 10W range, and that a critical winter temperature for many more temperate countries was - 10°C (14°F). For many cars, an oil in the 48-64 poise range at - 18°C (0°F) would provide 95-97% confidence of starting in the coldest month-January-and would best match their needs. Some diesel starting data, particularly on small, high-speed engines appeared to show the same trends.

The chemiluminescence determination of NO, and of NO2 after conversion to NO, is capable of yielding quantitative results for concentrations ranging from ppm to 1%. In using the chemiluminescence method for automobile exhaust, fast response and specificity are additional benefits. There are many possible sources of error in sampling, transporting, and analyzing auto exhaust samples, particularly when appreciable amounts of NO2 may be present. This paper discusses sources of error and how to detect and minimize or eliminate them.

Regarding the utilization of space and savings in vehicle weight and cost, greater demands are made upon compact cars than on larger automobiles. The development of compact cars, therefore, requires a higher degree of care and expense. The designer is forced to compromise more than he would in the case of larger vehicles. This paper examines some present day problems which are of particular interest with respect to driving safety when we regard the development of the chassis for compact automobles. These problems include suspension suitability for radial tires, axle kinematics, vibration characteristics, brake system design, handling, and legal requirements.

Wind tunnel tests were conducted on a series of 1/4-scale, 1/6-scale and 1/8-scale models of various automotive configurations utilizing a wind tunnel fitted with adjustable ceiling and sidewall inserts. Force, moment, and static pressure distribution data were acquired and used to develop corrections which appear to account for the constraints imposed on the flow field about these bodies by solid tunnel walls. In addition test section size limitations are defined for the acquisition of reliable data from automotive configurations.

A program was conducted to evaluate the performance characteristics and to determine cost effectiveness relationships associated with various prototype gasoline vapor control systems for service stations. Eight participating petroleum companies provided test facilities employing the direct displacement vapor control concept for evaluation during the summer, fall, and winter seasons. Test results indicated that the direct displacement systems had the potential for controlling approximately 95% of the vapors that normally are emitted when a tank truck delivers fuel to the underground tank and when tight connections at the vehicle fill neck are obtained. One petroleum company provided a refrigerated-condensation vapor control system for evaluation which exhibited the potential for virtually 100 percent vapor control, again when tight connections at the vehicle fill pipe could be achieved.

This paper outlines design considerations and criteria used to construct a prototype vapor balance gasoline nozzle. The nozzle incorporates a particular magnetic material on the face of the vapor recovery boot with a synthetic polymeric material on the sealing surface. A specific vapor recovery boot design is revealed which assists mating to the surface of the fill pipe. This nozzle was evaluated on 47 in-service vehicles at a specially equipped, commercial station in Chino, California. The prototype nozzle was solely supported by the automobile fill tube. Fill pipe-nozzle interface losses, car vent losses and station vent losses are all counted in the overall performance of the system. Percent vapor control was 88.9%. The investigators suggest that a fill pipe designed for vapor recovery would routinely yield results in the high 90s.

Several sets of repetitive test data using the 1975 Federal Test Procedure ('75 FTP) have been analyzed to establish the variability of each component measured during each phase of the test. The variability characteristics of four different emission control systems have been discussed and compared. The overall variabilities of the '75 FTP composite values have been assessed at ±6% for hydrocarbons and CO, ±3% for NOx, and ±1% for CO2. The extremely repeatable behavior of the CO2 emissions is utilized to calculate the fuel economy during the test. This calculation is discussed and some fuel economy results from repetitive tests are presented.

The use of high-pressure impingement mixing equipment for reaction molding of solid and cellular urethanes offers advantages in economics, molded product surface quality, and uniformity as well as the capability to produce parts on a short cycle time. This paper discusses some of the equipment available for reaction molding and reviews the history and products made with the process.

In dependency from the formulation of the initial components Polyol and Isocyanate, flexible, semi-rigid, rigid or structural Polyurethane foams are suitable for the most varied production of blocks or mouldings. It is the target of our review to present to you the latest standards of such processing techniques as are applicable to the manufacture of Polyurethane mouldings from the point of view of the automotive industry. In doing so, I shall make special mention of particularly developed, custom-made machines and installations.

This paper examines the problems involved in predicting the behavior of urethane foams made by reaction injection molding (RIM). In general, RIM urethane foams are formed from mutually soluble stable liquid components into a 60 pcf foam with a durometer hardness of 50D and with sufficient strength to be removed from the mold in one min or less. Since impact resistance also is important with the materials, the property of low temperature impact is a basic selection criterion. A fundamental problem is how the desired impact resistance can be obtained without sacrificing other needed properties. This study describes how the creation of a mathematical model, based on experimental data, can be used to predict how basic properties of RIM urethanes will change as key variables are altered.

This paper is devoted to the development of polyurethane raw materials for elastomeric exterior body parts and the potential use of such BAYFLEX parts in these applications. The results of the development of these types of urethane elastomers were demonstrated in 1974 with the production of flexible exterior body parts from BAYFLEX 100 SR at Krauss Maffei in Munich. This successful demonstration represents only a beginning for the large scale use of elastomeric exterior body components in automotive applications.

Two methods for obtaining aerodynamic pitching moment and lift information have been developed using road tests of drivable vehicles. First, improvements in the dynamics of manometer tubes make onboard measurement of pressure distributions feasible. Second, a method for determining pressure distributions on a vehicle's underside from the road is valuable in verifying the accuracy of wind tunnel tests; no vehicle modifications are required. Both methods should improve the state-of-the-art in automobile aerodynamic instrumentation and testing.

A new smoke tunnel to visualize airflow around three-dimensional models has been originated for a study of automotive aerodynamics. The necessity to develop the facility, its technical data, and some examples of visualization are discussed. The facility, whose test section is 1 m high, 1 m wide, and 1.5 m long, is provided for 1/6-scale passenger car models. Thirty-nine lines of kerosene vapor in a vertical plane make airflow clearly visible at the airspeed of 2-9 m/s. The high Reynolds number of 2.5 X 105, based on wheelbase, is obtained.

Recent developments in equipment for Reaction Injection Molding (RIM) combined with improvements in self-skinning foam technology and part design have given a new dimension to crash pad production in the automotive industry. An example of such production applied to the French market is presented. In addition, a brief comparison of self-skinning foam crash pads via RIM versus other processes is outlined.

A study of the airflow beneath an automobile relied on road tests of two test vehicles to reduce simulation errors caused by the moving road boundary. Testing verified the possibility of a very low Reynolds number boundary layer existing on the road beneath the vehicle. Flow separation associated with this boundary layer could have significant influence on the lift and pitching moments of the vehicle.

A schlieren-streak optical system for measuring instantaneous exhaust gas velocities was developed and tested using a CFR single cylinder spark-ignition engine. Local density gradients which move along with the local fluid velocity in the exhaust gas flow, were used as velocity tracers in the schlieren system, and their motion parallel to the exhaust pipe axis was recorded by a streak camera. The performance of the schlieren-streak system was checked with a calibrated hot-wire anemometer by comparing the instantaneous exhaust gas velocity data obtained by both methods in a motored engine. The agreement between the two methods was within ± 10%. The schlieren-streak velocity data were also compared with the results of a computer simulation based on one-dimensional unsteady gas flow. The computed instantaneous cylinder and exhaust pressures were within ± 8% of the measured values. The agreement between measured and computed instantaneous exhaust gas velocities was within ± 10%.

This paper presents an experimental technique for locating engine cooling system hot spots by using a Magnesium Borate water solution for the engine coolant. In doing so, Magnesium Borate is deposited wherever local boiling occurs thus indicating the high temperature areas. This technique was applied to a large V-8 engine and provided visual results of high temperature areas in the water jacket. Color photographs show the results, which correlate with measured metal temperatures and measured coolant flow velocities. The extension of the technique to include estimation of metal temperatures results from additional test data reported. The procedure is useful for locating unsuspected hot-spots in any passage in the engine cooling system. The severity of the temperature may be determined by knowing the Boiling Point of the solution.

High and low temperature performance of various urethane elastomers is discussed in terms of compatible/incompatible polymer theory. The influence of polyol molecular weight, low molecular chain extender and isocyanate are presented and discussed in terms of their effect on the modulus/temperature sensitivity of the elastomers studied.