Particle Image Velocimetry (PIV) has become a vital tool for Formula 1 (F1) aerodynamics development, as it provides aerodynamicists with a 2D snapshot of the actual velocity field around various areas of the car. This paper reviews an activity during the course of development of PIV system which is used for the wind tunnel development of a scale-model of the F1 car. Some unique technical features of the system are described in a brief history on how the system has evolved into the practical system, in which the user can easily use it as a tool during the development loop, without any technical knowledge of the system itself. Some episodes on what authors experienced during these try-and-error processes while developing the system are explained. It also shows one of the results obtained during the actual development by using this system.

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  To measure the flow around full scale vehicle and to understand its aerodynamic phenomenon is effective for the validation of CFD and the advancement of aerodynamic design.
  The flow around vehicle includes various scales of vortexes, so PIV is suitable measurement method to understand the relationship between these vortexes and aerodynamic performance, but measurable domain of PIV is not sufficient for full scale vehicle.
  Measurable region of Large-scale PIV developed by us is sufficient for the flow around just a component like side mirror or A-pillar, but is not sufficient for the wake flow of full scale vehicle that includes all of phenomenon.
  In this study, the relationship of magnification factor of camera, laser power density and PIV’s accuracy are clarified to realize ultra-large-scale PIV which is adopted data merged method with high accuracy.

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Flow field around the ship in manoeuvring motion is measured by using an underwater stereo PIV in order to obtain validation data for CFD analysis and investigate influence on the flow due to turning of the ship. Measurements are carried out in the manoeuvring test tank for model ship where planar running can be performed. Velocity distributions around the ship stern in turning motion are successfully measured and characteristics of the flow are discussed.

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  PIV technique is developed its spatial and time resolution with time, such as stereo PIV, dynamic PIV, holographic PIV, and tomographic PIV. Analysis algorithm is also developed, such as direct cross-correlation, FFT cross-correlation, recursive local-correlation, and ensemble correlation. However, there is not enough number of examples that PIV technique is applied to a pump. In this article, examples of PIV measurement by pump makers are introduced and issues are mentioned.

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The entrainment process and organized motions near a source of poof fire in a ventilation controlled compartment was experimentally investigated by using a particle image velocimetry technique with spores of lycopodium clavatum, the diameter of which decreases to several um in flame. Special attention was paid to the low ventilation effects: the compartment was poorly ventilated by a mechanical system with a meager negative pressure, and heat release rate of the pool fire and the oxygen concentration in the compartment decreased for the duration of fire, providing the transition to ventilation controlled fire. The transition drastically changed spatial and temporal structures of entrainment of ambient fluid. The fully developed fire generated puffing motions reported also by existing studies. On the other hand, the ventilation-controlled pool fire yielded meandering fluid motions. Such changes in structures activated entrainment of the ambient fluid.

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We develop a PIV system and validate it by measuring a grid-generated turbulence. We first show the background of this research before we approach the development of the system, and then, we describe the newly developed PIV system. We also describe an interpolation method, which we introduce into the PIV system, which notably decreases the uncertainty of PIV measurement. Then, we apply the PIV system to measurement of a grid-generated turbulent flow, and validate the PIV system by measuring the flow. First, an instantaneous flow field and basic characteristics of the flow are shown. Then, the energy decay of velocity fluctuation in the flow is shown, and coefficients of the decay law of the intensity are measured. Measuring the energy dissipation of the flow, we measure the value of these coefficients. The agreement of these coefficient values with those of previous experiments validates the PIV measurement.

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