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It is difficult to characterize the shaft surface, which is the running surface of the radial lip seal, by only using the average roughness, Ra. Usually, roughness measurement instruments provide a lot of other parameters besides Ra. A discriminant analysis can be applied to these parameters with seal function tests. The discriminant function generated from roughness parameters in addition to Ra and the results from functional tests could be a useful tool to classify the preferred and non-preferred shaft surfaces for seal applications. The logic of the discriminant analysis is presented. The application of the discriminant function in shaft surface classification is discussed. A case study of a real application is given. The benefit and the limitation of the approach are also discussed.

A new method to measure the temperature field of gas flow with infrared thermovision is introduced. By means of a plate with great heat capacity, the temperature field in a crossflow plate - fin heat exchanger is measured. The results are objective and reliable. Moreover, the error caused by this method is analysed, it indicates that this method is successful.

This paper presents the measurement & analysis procedures and the results of a complete road noise identification and reduction project on a midsize passenger car. Operational interior noise signals and structural accelerations are measured for several test conditions. The operating data are decomposed into sets of mathematically independent phenomena by Principal Component Analysis. Operating Deflection Shape Analysis and Transfer Path Analysis are applied to each of these independent phenomena. Critical transfer paths are thus identified and quantified. The interior sound level is amplified when the frequency content of the transmitted energy coincides with structural resonances or standing waves of the interior car cavity. The vehicle is dynamically characterized by Experimental Structural Modal Analysis and by Acoustic Modal Analysis.

A preliminary study was conducted to develop an automotive thermal energy storage unit for reduction in emissions and for increase in occupants comfort in winter. To prevent thermal storage performance degradation of the thermal storage media some additives were mixed with the base material Bariumhydroxide-octahydrated(Ba(OH)2·8H2O), and offers promising degradation-resist characteristics. The thermal energy storage unit was then optimally designed based on parameter study and empirical analysis. A comparison was made with a commercially available heat battery. Peak power of the developed thermal energy storage unit was about three times higher than that of the existing one.

With conventional automotive systems overall music sound quality depends on whether car is running or not. It is so because the low frequency component of the sound is masked by the road noise when running. To develop a system in which the sound is not easily masked by the road noise, we have paid attention to the difference between the speaker velocity changes (acceleration characteristics) due to the road noise and those of the music signal, and to the attack transient which is important to identify the timbre. The rise time response of the loudspeaker is a key factor for improvement, and conventional speakers have limitations in this regard. In 1995 the authors presented the New-AFB System1) in the SAE convention, which explained the technology and advantages of acoustic feedback in achieving flat sound pressure vs. frequency and enabling substantial improvement in response time of the speaker. Since then we have applied this to develop an optimum system for automobile use.

When attempting to resolve the flow over complex geometries with high Prandtl fluids using CFD, there is a large difference in the size of the hydraulic and thermal boundary layers. This leads to differing requirements for the grid resolution. In fact, resolution of the thermal boundary layer often leads to a grid size that is highly memory intensive. The following paper discusses this problem and outlines a method by which boundary layer similarity may be used as a possible alternative to these large grids.

An advanced magnetic system called Dual-gap Direct Drive (DDDrive) system has been developed. This supreme sound quality speaker shows an extremely low distortion level and high transient response to music signals. This very efficient magnetic system makes it possible to design both an ultra-light weight speaker for vehicles and a low flux leakage speaker for multimedia use.

A new automotive Mini Disc (MD) changer mechanism has been developed which fits a 1 DIN size chassis. This mechanism, mainly consisting of a disc change mechanism and an anti-vibration mechanism employing a floating disc drive unit system, offers a high vibration resistance, quick disc change capability and a size small enough to set a unit in an instrumental panel (I/P).

Adiabatic two-phase flow experiments have been carried out in an evaporator plate assembly which has entry and exit header vestibules on one side and a U pattern flow passage with round or cross ribbed protuberance in the channel. Over the practical flow range in common installation orientations, non-uniform distributions were found in both surface wetting on the internal walls of a single channel and the flow rates in a number of parallel channels. The poor performances of the plate surface wetting in single channel and the flow distribution in the multiple channels would severely limit the heat transfer capability of the current designs.

Copper steels are used to fabricate high strength parts. The alloys are useful because they exhibit high strength, hardness and wear resistance. Copper alloy contents of 2-w/o are most popular. Higher copper content is alloyed to increase wear resistance. In the as-sintered condition, these alloys achieve ductility of less than 1%. Of alloys containing from 2-w/o to 10-w/o copper with 0.45 or 0.8-w/o combined carbon, specimens were compacted at 425 or 640 MPa, and sintered using a cycle commonly applied in a belt furnace. The alloys were found to have combined carbon content within controllable limits. Contamination was low. The tensile strength of the sintered copper steel was higher than that of typical values listed in Standard 35. Elongation for 2-w/o-copper/9-w/o-carbon copper steels was 3%. For 5-w/o-copper/9-w/o-carbon copper steels, elongation was 2%. Processing and cost to obtain these properties is discussed. Additional work now in progress will also be discussed.

In the compact cassette and duplicating business for prerecorded cassettes, the importance of accurate azimuth alignment has grown over the years. Improvements in tape technology at the one hand and in recorder electronics and magnetic heads on the other extended the frequency response of the compact cassette system far beyond 10 kHz, resulting in continuously growing demands in azimuth accuracy. Three major effects will be discussed, which influence the audibility of insufficient azimuth alignment.

The problems of calculating non-steady temperature fields, in complex shaped axi-symmetric bodies in the processes of plastic forming as well as in working processes of ICE are concerned. A mixed method of solving this problem is proposed. According to this method, an axis section region of a complex shaped body is mapped conformally into a rectangle. A reduced boundary value problem for heat transfer is solved in this rectangle. The numerical method of a time-depending heat transfer modelling at the forming processes of impeller disk of a gas turbine is concerned.

The Digital Audio Broadcasting (DAB) system is the next generation broadcasting systems. DAB is high speed data broadcasting to mobile vehicle and can serve CD quality audio program and various data to drivers. Our prototype DAB receiver, that was developed in conformance with EUREKA 147 third generation format, has been successful in receiving actual DAB signals during reception testing. In this paper, our prototype DAB receiver is introduced and results of stationary and mobile receiving tests are described. In addition, we present the results of various laboratory tests, that were used as part of our evaluation of the prototype receiver.

Effects of high temperature sintering on mechanical properties of sintered low alloy steels were investigated. With regard to sintering temperature dependence of mechanical properties, as-sintered steels are classified into two groups. High temperature sintering increased strength of the group1 steels and ductility of the group2 steels, while it did not affect ductility of the group1 steels and strength of the group2 steels. When these steels were heat treated after sintering, both strength and ductility of the steels obtained by high temperature sintering were superior to those of the steels of a conventional sintering process.

CouponRadio standardizes the content and structure of the data broadcasters transmit on their Radio Broadcast Data System/Radio Data System (RBDS/RDS) FM 57KHz subcarrier. Because of this new interactive standard, specially designed receivers will not only receive and display the changing messages. More importantly, the receivers will allow the listener to selectively save the messages of their choice onto removable credit card-like memory devices, which can be left in the radio for safely viewing the messages later, or removed from the radio to generate valuable electronic coupons at local retailers. The patented Interactive Multi-Industry Standard (IMIS) will give electronics manufacturers the direction and confidence necessary to build a new era of radio receivers that will be well received in the marketplace.

Due to recent developments in ferrous powder metallurgy, production of high performance parts has become more cost competitive. Advances in high performance materials have provided high strength in as-sintered components. With recent technological developments, high density parts (>7.3 g/cm3) can be fabricated with a single compaction process that also provides green strengths significantly higher than obtained with traditional processes. Properties obtained with these materials are described and the use of Mn and Cr as alloying elements are reviewed. Machining high performance P/M materials is difficult. A method of green machining P/M components by taking advantage of the material's high green strength is introduced.

Since many years sinterforged con-rods produced via different forging processes (near net shape or net shape forging) are successful in operation in several automotive engines. Latest results of different con-rod projects (partially funded by the German Government) show that even sintered components with densities in the range of 7,1 g/cm3 offer fatigue strength values comparable to those of sinterforged con-rods. The processing has a major influence to the fatigue behaviour and to machinability. Experiments with test bars allow only limited correlation to real components. So it is necessary to compare performance and cost-structure of finished con-rods to give a reliable evaluation for the capabilities of different manufacturing routes.

Today's car radio design is based mainly on analog signal processing. The need for higher integration of the receiver is becoming of major importance, since various new features (i.e. GSM, Navigation etc.) will be added to the radio. The proposed concept goes beyond known designs of baseband processing: (1) digitalization of the intermediate frequency (IF) signal, (2) digital processing of all subsequent stages and functions. A digital car radio receiver (DCR) based on a chip set consisting of a frontend bipolar IC and CMOS IC for the digital signal processing is presented.

This paper presents a new design method for solving the vehicle vibration problem induced by engine drive, by using a μ-synthesis. We have tried the active control of engine mounts to insulate the vibration of engine. We experimented on the effects by using computer simulation and vibration simulator. Computer simulation results show that resonance peak can be effectively reduced. We have also confirmed the effect of vibration simulator, which shall be reported in this paper.

Virtually all automotive systems are subject to intense commercial, market and legislative pressures to evolve in new directions. The exhaust system is no exception. The relentless drive to: reduce costs, to extend warranty and service life, to respond to customer cosmetic preference for bright metal under hood combined with emission legislation demanding zero leakage stretch the imagination and resourcefulness of the industry. Powder metallurgy (P/M) has a role to play in this regard. The complex and accurate net shape capability and material versatility of P/M provides an attractive combination for several components especially flanges. A hindrance, however, is lack of a materials property database relating to the special properties required for service. High burnt gas temperatures in exhaust systems produce internal corrosion oxidation attack, and stress relaxation of joints while road salt attacks the external surfaces.