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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.

Most automotive piston engines employ a front-mounted, belt-driven coolant circulation pump. The pump shaft is normally supported by a double row rolling-element radial contact bearing. The engineering analysis for an improved method of water pump bearing service load and life prediction is described here. This general analysis considers most of the design variations which are found among engines, water pumps, and bearings in current use. A rather thorough accounting has been made here of the various sources of bearing loading occurring in this application. Bearing life is determined according to the recently revised A.F.B.M.A. standards.

The temperature history at a location in the combustion chamber of a spark ignition (SI) engine is determined by using the intensity of radiation from the recombination continuum CO + O ↠ CO2 + hv. The flame was initiated separately at two locations in the combustion chamber while the radiation was monitored at one location thereby making the arrangement somewhat equivalent to monitoring the radiation from two different gas zones in the chamber. Agreement between the predicted temperature history with heat transfer and the experimental temperature measurements was found to be good around the stoichiometric region but large differences were noticed when the engine was run at lean mixture strengths.

A suite of computer programs has been developed for the analysis of loading and lubrication characteristics of rotor bearings and main bearings in the rotary engine. The lubrication analysis was very similar to that for reciprocating engines and required only very slight modification.

A fleet of 64 heavy-duty 1970-71 model trucks and buses powered by a variety of diesel engines were tested periodically to determine exhaust smoke behavior. Smoke tests were made when the vehicle was new or nearly new and at four month intervals thereafter, or until 160,934 km (100,000 miles) odometer reading was reached. Gaseous emissions of hydrocarbon (HC), carbon monoxide (CO), and nitric oxide (NO) were measured at one point early in the project. Both smoke and gaseous emission tests were performed with chassis versions of the engine dynamometer Federal Test Procedures (FTP). Results in terms of “a” (acceleration), “b” (lugging), and “c” (peak) smoke factors versus mileage are reported for the 13 engine-vehicle-application groupings.

The Ford Auto/Emission Driver System automates the driving of a test vehicle on a chassis dynamometer while it is undergoing exhaust emissions testing. The system “drives” the vehicle through the 1372 s EPA Urban Dynamometer Driving Schedule associated with the CVS-C and CVS-CH Test Procedures by applying the accelerator and brake pedals directly and also shifts the transmission if the vehicle is equipped with a standard transmission. The Ford Auto/Emission Driver System consists of a hybrid analog and digital electronic control console including a magnetic tape recorder and a servo hydraulic mechanical console linked to universal interface fixtures in the vehicle via flexible mechanical push-pull cables. The high response hydraulic rams are mounted remote from the vehicle to permit design of actuating fixtures which are compact, light weight and therefore easy to install.

This paper describes a new, closed-loop programming system which faithfully transfers road operation to the chassis dynamometer. The system provides stable, rapid, accurate response to programmed speed and throttle position changes. Using a derivative of a torque-related signal, changes in power train performance are compensated realistically by electronic modification of either throttle or speed signals as a function of part or wide open throttle command. Under conditions of minor power loss, part throttle compensation is found to restore such uncontrolled parameters as engine speed and driveline torque to the values measured without engine degradation.

This report describes the results of a surveillance study initiated by the U.S. Environmental Protection Agency to measure gaseous exhaust emissions from 1020 light-duty motor vehicles. This project was the second effort in a continuing program using the CVS Federal Test Procedure. Selected privately-owned vehicles, drawn randomly from six metropolitan areas, were tested in as-received condition. The emissions data obtained from these 1966-1972 model-year vehicles are reported in grams per mile of unburned hydrocarbons, carbon monoxide, carbon dioxide and oxides of nitrogen while fuel economy is reported in mpg as determined over the Federal Driving Schedule.

Methanol's potential as a gasoline extender has been evaluated, with data being obtained in the areas of fuel economy, exhaust emissions, and driveability. The results of tests with three cars, having carburetion spanning the range normally encountered in the existing car population, showed that methanol's effect on fuel economy and emissions could be directly related to its leaning effect on carburetion. The data suggest that any benefits in these two areas would only be significant for older, rich-operating cars. A 13-car driveability study indicated that the large increase in fuel volatility which occurs with the addition of methanol to gasoline could pose serious problems. A marked increase in vapor locking tendency was observed when no front-end volatility adjustments were made to the methanol blends. Stretchiness, a lack of expected response to throttle movement, was also found with the methanol blends.

Methods are discussed for obtaining in-service loads, motions, and operational parameters on customer-operated vehicles. Special load measuring transducers and unique unattended monitor recorders were utilized. Some statistics associated with selection of field customers are discussed.