Two typical flows in an internal combustion engine are represented by means of video display of the velocity vectors which are measured by laser Doppler anemometer (LDA).
The first experiment is velocity and turbulence measurements in the wedge-type combustion chamber of a two-cycle spark ignition engine. The combustion characteristics have also been observed by using high-speed shadowgraph photography, pressure and ion currents in the chamber installed in different manners on to the cylinder. The results indicate that the flow fields vary not only with arrangement of the combustion chamber but also depending on motored and firing operations due to the expansion flow of combustion. The second one is LDA measurement of continuous velocities of fuel spray from a single hole injection nozzle of a Diesel engine and air movement around the spray. Time dependent profiles of mean velocity are presented and compared with those in the steady spray flow. It is found that the air is entrained after being pushed away by the spray and a large amount of air is entrained in the spray.

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To clarify critical conditions which Taylor vortices occur in pivoted-pad, journal bearing, fluid flow was visualized by means of hydrogen bubble method and was pictured utilizing a video camera recorder. The experiments were carried out to simplify for one and four fixed-pad journal bearing.
The experimental results obtained are summarized as follows.
In one fixed-pad journal bearing, Taylor vortices occured small value than the value calculated by Taylor's theory. In four fixed-pad journal bearing, it was similar to one pad, too.

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In order to develope the more effective method of the aerosol therapy, it is very important to investigate the flow patterns in the nasal cavity and the paranasal sinus, especially in a maxillary sinus, precisely. Then, flow visualization was done by using a dry-ice and a glycerin-water mixture mist as the tracers. As a result, there exists very weak flow from the nasal cavity to the maxillary sinus through the small opening of the maxillary sinus. It was also clarified that the flow pattern of the nasal cavity is so reasonable and complex. There exists two swirls at least. On the other hand, the flow pattern in the paranasal sinus is very weak, simple and almost laminar.

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Flow phenomena in the agitated vessels are estimated quantitatively by 2D Particle Imaging Velociaetry. Velocity vectors near the two kind of impellers.3 blades propeller and 4 blades pitched-paddle, are stored and converted to stream line, vorticity distributions and kinetic energy contours.
Vortex structure is observed separately in the case of 3 blades propeller. The difference of flow patterns between 3 blades propeller and 4 bladespaddle is also discussed.

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To make a good air conditioning in a vehicle passenger compartment, it is necessary at first to know about the air flow in it. This paper describes the results of visual experiments on air conditioning flow in the sedan typed compartment of 1/5 scale model. An air conditioning mode mesured by 2 dimensional LDA with 3 beams is the cooling and internal circulating mode.
According to this experiment, we could visualize the state of vortices in the compartment and make clear the difference of flow pattern at the front part of the compartment from the rear part. Further, the effectiveness performing 2 dimensional experiments was discussed by comparing previous 3 dimensional results with 2 dimensional ones.

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In this study, the velocity distributions of the flow in 1/4 model of air conditioned car room were measured by "Twinkle-Laser-Sheet Technique" which is based on the flow visualization technique of the so-called tracer method. As a result, the jet flow from the nozzle in front of the front sheet and the existence of local recirculating flows were clearly shown. Moreover, it was known that the counter jet flow from the nozzle beside the foot-rest made better flow pattern in the model car room. It has been confirmed from the present experimental study that this velocity measurement technique could be one of the simplest and most convinient methods for 3-D and complex flow fields.

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Recently, highly shear-thinning gas injection for materials in dredging pipeline is generally used for head loss reduction. However the rationalistic efficiency prospect is not clear yet. In this paper, we selected a model for gas-liquid slug flow and theoretical expressions by the visualization in a dredging pipe.

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In order to analyze the flow of fresh concrete mixed in a truck agitator, a new technique was discussed in this paper. With help of visualization technique it became possible to obtain the information about movements of coarse aggregates and mortar in fresh concrete model.
For visualizing the concrete flow, concrete was replaced by the model concrete made of transparent motar and artificial lightweight coarse aggregates.
In addition, the truck agitator was also modelized by the transparent plastic material with a scale of one fifth of prototype.
The video system was used for recording and analyzing the movement of aggregate. Introducig the Lacey's method, the mixing of aggregates in a truck agitator was discussed concerning the effects of the volumetric ratio of coarse aggregate to mortar (Vg/Vm), viscostiy of mortar and the volume of concrete.

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