Nuclear Techniques ›› 2019, Vol. 42 ›› Issue (8): 80603-080603.doi: 10.11889/j.0253-3219.2019.hjs.42.080603

• NUCLEAR ENERGY SCIENCE AND ENGINEERING • Previous Articles     Next Articles

Telecentric PIV measurement of lateral flow in rod-bundle fuel assembly

Zenghui ZHI Zheng QU Wenhai CHEN Shilong XIONG Jinbiao WU   

  1. School of Nuclear Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
  • Received:2018-05-29 Revised:2019-02-28 Online:2019-08-10 Published:2019-08-26
  • Supported by:
    National Natural Science Foundation of China(51676120)

Abstract: Background

Mixing vanes are set on the spacer grids of bundle fuel assembly to promote the lateral mixing of pressurized water reactors (PWRs). Hence, the lateral flow downstream of the spacer grids is an important element to measure its thermal-hydraulic performance.


The study aims to tackle the challenge of measuring lateral flow using visualization method.


A telecentric optical system was employed in the particle image velocimetry (PIV) measurement to efficiently reduce the distortion of the image. In addition, the fluorinated ethylene propylene (FEP) tube was utilized as the matched-refractive-index material of the work fluid in the measurement area to minimize the focusing effect after the transparent rods and realize the uniform illumination of the whole section of the rod bundle. Calibration and lateral flow measurement were conducted to evaluate its performance.


Experimential results show that the lateral flow and vortices can be well obtained on the whole cross section of the 5×5 rod bundle by PIV telecentric measurement.


The measured flow fields indicates that the dominant effect of the mixing vanes on the lateral flow 5D h downstream and its effect decays further downstream.

Key words: Particle image velocimetry, Telecentric optical system, Matched index of refraction, Spacer grid, Lateral flow

CLC Number: 

  • TL99,TL332