Dynamic PIV

Gpu-piv

Digital Particle Image Velocimetry (PIV) is an optical technique used to measure the velocity of seeded particles in real flow. A CCD camera captures the flow field twice under exposure to a short duration laser flash. Recorded image pairs are cross-correlated to extract velocity information from these records. Time resolved PIV technology can capture images with some hundreds of frames per sec...

PIV Measurements in Pumps

Digital Particle Imaging Velocimetry (DPIV) is a powerful nonintrusive measuring technique that has become popular in the last decade with the availability of commercial systems. In contrast to Particle Image Velocimetry (PIV), which utilizes analogue imaging and therefore time-consuming post processing, for DPIV digital video recording is encountered which is ideally suited for digital data pr...

PIV uncertainty propagation

This paper discusses the propagation of the instantaneous uncertainty of PIV measurements to statistical and instantaneous quantities of interest derived from the velocity field. The expression of the uncertainty of vorticity, velocity divergence, mean value and Reynolds stresses is derived. It is shown that the uncertainty of vorticity and velocity divergence requires the knowledge of the spat...

ارزیابی روش PIV در تعیین مقیاس‌های آشفتگی

با توجه به پیچیدگی­ها و کاربردهای فراوان آشفتگی جریان، شناخت صحیح و کمّی مقیاس­های این نوع جریان در مسائل مختلف اهمیت ویژه­ای دارد.  به­منظور تعیین مقیاس­های آشفتگی، از روش­های آزمایشگاهی متفاوت می­توان بهره جست.  اما نکتة مهم در استفاده از این روش­ها، صحت و دقت آنهاست.  در این مقاله ابتدا ضمن بررسی روش مرسوم تیلور جهت تعیین مقیاس­های آشفتگی، روش تعیین ضرایب همبستگی با استفاده از تکنیک­های آزمای...

Visualization of three-dimensional vortex structures around a dragonfly with dynamic PIV