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New icephobic paint has been developed for the purpose of preventing the icing of the airfoils of aircrafts. The basic characteristics of the paint in terms of icing prevention were examined by an optical method and a load test. The water contact angle is so high-150 degrees-that high water repellency can be obtained as expected from the design. The adhesion strength of the ice formed on this coating is decreased to the lowest value as compared to all paints ever developed. The results from the icing wind tunnel test carried out in conditions similar to what aircrafts encounter show that the paint contributes to fuel and weight savings due to the effective use of deicer.

A new off-road vehicle generation for the Swedish Army has been developed. It is now being produced. The program covers two off-road truck families, one articulated tracked all terrain vehicle and one motorcycle. A procurement method aiming at minimized and controlled life cycle cost has been applied. In this an incentive, which will give the finally proved maintenance quality of the product an impact on the unit price, has been introduced. With the procurement method as a background the four concepts are presented. Finally the results and experiences of the procedure are discussed.

A typical underhood cooling air system is driven by a cooling fan. Computational Fluid Dynamics (CFD) is frequently used to simulate the underhood air system and the fan performance. Underhood CFD analysis consists of two separate cases, the fan-installed case and the system restriction case. System restriction plays an important role in the initial fan selection process for a new cooling system design. In the current test and modeling method, the force driving the airflow is located at different locations in the fan-installed case and the system restriction case. For a system with a bypass between the inlet grill and the cooling package, due to the differences in driving force location, the air at the bypass flows in opposite directions in the two cases. Therefore, the system restriction predicted or measured using the current method is different from the restriction the fan “sees” in the fan-installed case.

Laboratory performance testing of larger tires requires system capability beyond larger diametric clearance and additional radial load capability. This paper describes a newly introduced Flat-Trac® tire test system designed for light truck tires and racing tires. Background on flat surface force and moment testing identifying the need for a system with more capability is presented. The MTS Flat-Trac LTR tire test system is introduced as a force and moment measurement system capable of testing light truck and racing tires. The first of these systems has been in operation at Bridgestone's Tokyo technical center since July 2002. Test results are presented to show that the Flat-Trac LTR (Light Truck/Racing) provides increased capability beyond the conventional Flat-Trac III CT (Cornering and Traction) system. Cornering force and longitudinal force test results are compared to show agreement between the Flat-Trac LTR and Flat-Trac CT systems.

This paper presents a new system for controlling the braking force between the inner and outer wheels in a turn independently. Vehicle cornering performance has improved noticeably in recent years thanks to advances achieved in tire and suspension technology. Due to this improvement, vehicle handling characteristics during braking have taken on added importance. To achieve stabler handling properties during braking in a turn, a new evaluation method is being used at Nissan to analyze vehicle directional stability. The analytical results show that decreasing the yaw moment before wheel locking occurs is effective in achieving stabler handling. An effective approach to decreasing the yaw moment is to control the braking force between the inner and outer wheels independently. Base on these analytical results and experimental data obtained with actual vehicles, a new system has been developed that provides such independent control over the braking force.

A new system which has the capacity to inject and control the combustion of coal slurries in diesel engines is describe. The system eliminates the negative impact of coal slurries on the injection process, improves combustion of coal slurries, eliminates or greatly reduces the wear of the fuel delivery hardware, and prevents the nozzle clogging.

This article presents a new system for the measurement on small samples of the normal-incidence Insertion Loss (IL) of multilayers used for the manufacturing of automotive sound package parts. The system consists of a rigid piston connected to an electrodynamic shaker and facing a tube positioned just above it. The measurement principle is based on the evaluation of the Transfer Matrix (TM) of the piston-and-sample assembly, from which the desired IL can be calculated. The TM can, in turn, be evaluated from the measurement of the piston velocity and of the acoustic pressure inside the tube, with two different tube termination conditions. The proposed measurement system is first of all aimed at simplifying the assessment of the acoustic insulation of multilayers used for the manufacturing of sound package parts.

The new Thermo-Elasto-Hydro-Dynamic (TEHD) code developed by FEV, is designed to improve the predictability of journal bearing designs and thereby increase the reliability of safety factors in the development of highly loaded internal combustion engines. Advanced analysis tools are evaluated by their performance as well as by their ease of use. High performance means on the one hand: taking into account all the important characteristics, like bearing elasticity or cavitation effects, to mention only some major parameters for modern journal bearing analysis. On the other hand: an economic run-time behavior must be a key feature concerning usability of the TEHD-demands for daily development praxis. Ease of use means also, that the TEHD model can easily be used as a plug-in routine of an already existing software package that is well known to the development departments.

The porous medium approach is widely used to represent high-resistance devices, such as catalysts, filters or heat exchangers. Because of its computational efficiency, it is invaluable when flow losses need to be predicted on a system level. One drawback of using the porous medium approach is the loss of detailed information downstream of the device. Correct evaluation of the turbulence downstream affects the calculation of the related properties, e.g. heat and mass transfer. The novel approach proposed in the current study is based on a modified distribution of the resistance across the porous medium, which allows to account for the single jets developing in the small channels, showing an improved prediction of the turbulence at the exit of the device, while keeping the low computational demand of the porous medium approach. The benefits and limitations of the current approach are discussed and presented by comparing the results with different numerical approaches and experiments.

A central problem in noise control involves the calculation of sound radiation and the holographic reconstruction of sources. A standard method for such calculations employs boundary elements and the surface Helmholtz integral equation (SHIE). However, difficulties occur at frequencies for which a congruent pressure-release boundary would have interior resonances. In such cases the SHIE does not have a unique solution and the matrix used in the boundary element method is singular. This talk will present a new technique which employs both eigenfunction expansions (typically using spherical wavefunctions) and boundary element matrices. This new method avoids problems with internal resonances and singular matrices, does not require adding internal “CHIEF” points, and permits fast and accurate holographic reconstructions for arbitrarily shaped sources.

Present techniques for classification and analysis of surface roughness are based on a trace of surface profile, or a measure of arithmetic mean, or rms value of the profile height, but this information is not adequate, and a new technique has been developed to classify surface roughness based on frequency content of the variance of the surface profile. A digital computer frequency filter has been devised to allow differentiation between roughness height and waviness or general surface contour. Three representative surfaces have been measured and classified according to this analysis and data are presented in support for roughness classification techniques.

The accuracy of computer model simulations of dynamic events relies on the quality of the mechanical property data sets of the systems they represent. A new technique for determining the bending stiffness of mechanical necks has been developed at the Crew Systems Directorate of the Armstrong Laboratory, Wright-Patterson Air Force Base, Ohio. The Static Neck Tester (SNT) is a test fixture that statically loads and unloads mechanical necks in flexion, extension, and lateral bending. The base of the neck is rigidly fixed while a pure bending moment is applied to the top of the neck. A torque sensor measures the resistive torque of the neck to the applied bending moment. Two rotational potentiometers measure the neck angle and a linear potentiometer measures the linear compression of the neck between the end plates. Loading and unloading flexion, extension, and lateral bending tests were conducted on Hybrid II and Hybrid III necks.

A technique for field durability testing of elastically mounted components of off-road vehicles has been developed which simplifies the replication of field damage on these structures. The procedure combines the techniques of cummulative damage and modal analysis to replace the usual multi-shaker excitation technique with a much simpler physical system. This method allows field damage studies to be performed with less laboratory equipment and setup. Initial work has shown that the method is very effective in predicting field failures in an accelerated laboratory test.

Pulse width modulation (PWM) has been used to alter the performance of on-off hydraulic control valves to make them perform as proportional type flow control valves. Nonlinear performance resulting from time delays in valve switching as well as valve wear due to continuous cycling continue to persist as operational problems. This paper examines a new technique called modified PWM control. The method was found to provide accurate control with a minimum of valve chatter.

Using a novel, high frequency response FID unit, hydrocarbon measurements in the spark plug gap of a firing gasoline engine have been made. These measurements have been correlated with the pressure development, and a significant correlation was found. The method described can be used on any engine fitted with a modified sparking plug.

A new system for measuring spider compliance has been developed. The result of the measurement is a plot that maps the compliance versus displacement. The technique quickly and nondestructively generates the data and is almost completely automated. The method is reviewed and results documenting performance and improvement over an EIA standard test are presented. Several examples of actual measurements that illustrate the usefulness of the measurement are shown as well.

The distortion of the cylinder liners of internal combustion engines has a significant affect on engine operation. It can affect the lubrication oil consumption, the blow-by, the wear behaviour and due to the friction, the fuel consumption. In order to achieve future requirements regarding exhaust emissions and fuel consumption, the requirements for low cylinder distortion engine blocks will play a significant role. Hence, a new technique to determine liner distortion during fired engine operation was developed.

This paper addresses the longstanding problems of residual gas measurement during engine dynamometer testing, and of real-time residual modeling for engine control applications. A new method is described which is simple to apply, requiring only currently standard calibration test cell instrumentation. Experimental validation against measurements using direct in-cylinder CO2 sampling is presented, and a comprehensive error sensitivity analysis is included. A real-time capable, controls-oriented model is also described. Its accuracy is assessed by comparison to engine-simulation-generated residual values after using these values to determine the model parameters.

A simple colorimetric method for determination of base number (BN) [1] in used engine oil with test strips was developed. As oil ages with use, the alkalinity decreases. Thus titration methods are commonly employed for the determination of BN. In this research, test strips were constructed using a pH indicator impregnated in a membrane filter. The color of the test strip changed from pink to green with sufficient alkaline in the engine oil. When the membranes are acid pretreated, this method can discriminate among different degrees of BN loss. Thus the new technique has been successful applied to judge the degradation stage of engine oil.

A high-temperature tensile impact experimental technique, based on a rapid-contact heating method, is developed to test specimen at temperatures up to 1073K. High-strain-rate tensile responses of commercially pure titanium at elevated temperature are investigated. The testing results show that the yield stress and ultimate tensile stress all decrease with increasing temperature, while the fracture strain decreases with increasing temperature at the temperature range 25 °C350 °C.