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This paper describes a proposal of techniques on Transfer Path Analysis (TPA) to analyze transmission of vibration among the components in a complex structure. This proposal is evolved from the previous one [1] in the dimension which dominates the quality of the analysis in automotive body structure by TPA. The proper coordinate transformation was introduced to resolve the troublesome process on the application of the body structure in the previous proposal. The complications are caused by the treatment with a lot of transfer functions and transmitted forces at the conjunctions that are complexly assembled with many adjacent nodes. Dimension of the analytical region is expanded from two to three in this study. That is, from the cross section of interface of components to the structure itself where the vibration transmits between two components.

Improvement of vehicle interior noise is desired in recent years in the modern world of the demand of low weight, good fuel economy and offering technical advantages strongly. The dynamic force transmission of rolling tires from the road surface to the spindles is a critical factor in vehicle interior noise. We focus on structure-borne noise transferred through the spindle. It is necessary for effort of the effective tire/road noise reduction to predict spindle force excited by tire/road contact. The major issues in predicting spindle forces are to clarify the distribution of road forces and how to input on the simulation model. Therefore, it is important that road forces are measured accurately on the rolling tire. First, the dynamic road forces on the rolling tire are measured by using the tri-axial force sensor directly. In efforts to reduce interior noise due to structure-borne noise, it is necessary to predict spindle forces excited by the tire/road contact.

It is very much necessary for researchers and engineers whose work is the field of combustion in a CI engine to find the information of droplets in a diesel spray. The information is strongly required to construct the model of spray built in the numerical code for its simulation and to be used for the verification of the accuracy of the calculation. This paper describes the photographing system with high spatial resolution, the distribution of droplet size and the vortex scale caused by the droplets motion by means of this system.

In order to reveal the mechanism of noise generation from CVT (Continuously Variable Transmissions) using a dry hybrid V-belt, the power spectrum of sound from a two-pulley CVT system and its variation with respect to rotational speed were measured. The experimental results showed that the frequency of the first peak in the power spectrum of the observed sound linearly increased with increasing the rotational speed of the pulley. The sound frequency of the first peak coincides with the frequency derived from the belt block pitch and the belt speed. Then, sound intensity analyses were conducted to identify noise sources of CVT. The experimental results reveal that unpleasant sound whose frequency is high occurs due to the collision or slip between CVT blocks and the pulley groove at the entrance and the exit of V-groove pulleys. Pulley surface roughness strongly affects the noise level. Additionally, the location of noise source varies due to surface roughness of the pulley groove.

The maximum liquid-phase penetration and vaporization behavior was investigated by using simultaneous measurement for mie-scattered light images and shadowgraph ones. The objective of this study was to analyze effect of variant parameters (injection pressure, ambient gas condition and fuel temperature) and fuel properties on vaporization behavior, and to investigate liquid phase penetration for the single- and multi-component fuels. The experiments were conducted in a constant-volume vessel with optical access. Fuel was injected into the vessel with electronically controlled common rail injector.

Two-layered clutch plates manufactured by a new process using BMC show a significant deflection. Two methods solving such deflection were alternatively developed in this study. Changing the composition of the clutch plate appeared to be useless while after-curing on deflected clutch plates was effective. Thermal cycles or high pressure for after-cure did not reduce the deflection. However, applying after-cure with a sloped mold reduce the deflection without increasing the disk density.

This work investigates the soot formation process in diesel jet flame using a detailed kinetic soot model implemented into the KIVA-3V multidimensional CFD code and 2D imaging by use of time-resolved laser induced incandescence (LII). The numerical model is based on the KIVA code which is modified to use CHEMKIN as the chemistry solver using Message Passing Interface (MPI). This allows for the chemical reactions to be simulated in parallel on multiple CPUs. The detailed soot model used is based on the method of moments, which begins with fuel pyrolysis, followed by the formation of polycyclic aromatic hydrocarbons, their growth and coagulation into spherical particles, and finally, surface growth and oxidation of the particles. The model can describe the spatial and temporal characteristics of soot formation processes such as soot precursors distributions, nucleation rate and surface reaction rate.

In a typical mechanical product such as an automobile or construction machinery, it is important to identify deformation modes, for which experiments and analyses can result in significant improvements. It is also important to consider how to improve the structure with high rigidity by using a technique such as the strain energy method in conventional design and development. However, the abovementioned method often generates conflicting results with regard to weight saving and cost reduction of development requirements. Transfer path analysis (TPA) using the finite element method (FEM) is an effective way to reduce noise and vibration in the automobile with respect to these issues. TPA can reveal the transfer path from the input to the response of the output point and the contribution of the path, and to efficiently consider improved responses.

An advanced numerical model is proposed to analyze the power transmitting mechanisms of a CVT using a metal V-belt. By using the present model, forces acting on the belt are well estimated not only at steady states but also during transitional states where the speed ratio is changing. The numerical results show that blocks are in compression in both strands when the speed ratio is rapidly shifted. A complementary model is also developed to analyze the load distribution among bands which form the ring. The load distribution in the ring is governed by the difference in coefficients of friction among elements.

To reduce tire/road noise, it is important to examine the noise generation mechanism. Noise generated by a rolling tire is mainly emitted from the tread block. However, it has recently been reported that smooth tires also generate noise recently. This paper remarks on a smooth tire vibration by rolling on the road. The vibration of a rolling smooth tire is mainly vibration excited from the road surface. It is difficult to measure the input from the road surface, so we measured the tire's vibration at the leading and trailing edges. Scan Laser Doppler Vibrometers were employed to measure the vibration of the tire tread.

Almost all the researches relating to the characteristics of transient spray have carried out by using the fuel with only single component. However, the actual fuel oil supplying to a reciprocating engine has multiple components. Thus, this paper describes the experimental results on the characteristics of a transient spray formed by the mixed fuel with three kinds of pure fuel. The state of periphery of non evaporating spray near the nozzle outlet was arranged by the dimensionless number. And the technique of laser Induced fluorescence (LIF) was applied to an evaporating spray to find the state of mixing.

This paper describes the soot behavior in a diesel flame. The experiments were carried out in a constant volume chamber with quiescent atmosphere. Parameters were the ambient temperature and the oxygen concentration. The integrated image of flame was taken, the natural emission of flame was detected and the KL factor was found by means of classical technique of laser light extinction. The results were discussed by use of the apparent rate of heat release. As a result, the ignition delay and the vortex with large scale generated in a diesel spray affect the soot behavior in a diesel flame.

The combustion phenomena in an IDI diesel engine having a swirl chamber were detected by optical methods. The spatial and temporal distribution of the natural emission of OH radical was measured through the band pass filters and those of KL factor and flame temperature were obtained by the two-color method. As a consequence, the combustion phenomena are made clear by these experimental results.

A new discrete model was developed in order to analyze the power transmitting mechanisms of a dry hybrid V-belt CVT not only at steady states but also at transitional states where the speed ratio was changing. Block tilting in the pulley was considered in the advanced numerical model as well as pulley deformation due to pulley thrust. The validity of the present model was well confirmed by comparing the calculated results on transmitting and normal forces with the former experimental results. The calculated results showed that both block tilting and pulley deformation meaningfully affected the pulley thrust ratio between the driving and the driven pulleys.

The atomization structure of the fuel spray is known to be affected by flow conditions and cavitation inside the nozzle hole. In this paper, the cavitation phenomena inside the nozzle hole was visualized by using large-scale transparent nozzles, as well as the effect of length-to-width ratio (l/w ratio) of the nozzle hole on cavitation and on the behavior of injection liquid jet. In addition, various flow patterns inside the nozzle hole same as experimental conditions were simulated by the use of Cavitation model incorporated in Star-CCM+, which was compared with experimental results.

The objective of this study was to investigate the change of relative local velocity in each pulley groove at sliding between the belt and pulleys for a metal-pushing V-belt type CVT where micro elastic slips were inevitably accompanied to transmit power, while the transmissions were widely adopted to provide comfortable driving by continuously automatically adjusting the speed ratio. Local changes of wrapping radial position and velocity of the belt in each pulley groove of the CVT were simultaneously measured by a potentiometer with a spinning roller in the experiments. The mechanical power generated by the AC motor was transmitted through the CVT unit from the driving axis to the driven axis as usual under practical conditions while the speed ratio was set to 1.0. Pulley clamping force was applied by oil pressure.

In this study, the authors analyze the concentration distribution of an evaporative spray mixture with LIEF (Laser induced exciplex fluorescence) method, which is a type of optical measurement. LIEF method is one of the optical measurements for obtaining the spray concentration distribution for separating vapor/liquid phases based on the fluorescence characteristics. In this paper, a quantitative concentration distribution analysis method for wall impingement spray in heterogeneous temperature field has been proposed. Then, a series of experiments were performed in varying injection pressure and ambient density. As a result, a two-dimensional concentration distribution was obtained for the free spray and wall impingement spray.