Hits:

Indexed by:期刊论文

Date of Publication:2017-10-01

Journal:ADVANCES IN ENGINEERING SOFTWARE

Included Journals:SCIE、EI、Scopus

Volume:112

Page Number:117-123

ISSN No.:0965-9978

Key Words:Oceanographic techniques; Fluid flow measurement; Image edge detection; Image segmentation; Image motion analysis

Abstract:Research on changes in the fluid edge of a wave flume is important for experimental hydrodynamics. However, disturbances often occur because of the presence of sensors. To solve this problem, a new greyscale image processing method for fluid edge analysis is presented here. By fusing methods combining image gradients and image segmentation with shifting-window technology and with concepts derived from experimental fluid mechanics, the proposed method can overcome many of the inherent challenges of fluid-edge measurement. First, the geodesic distance is modified to obtain a class curve. Second, an edge position is determined by the inflection point of the class curve related to the gradient peak distribution. Next, the position of the interrogation window is relocated with reference to neighbors or to previous results, and the current edge position can be calculated according to the predicted value. During the computation, the interrogation window can change its position adaptively with fluid motion, ensuring that the amount of data to be analyzed always remains stable. A model combining the class curve and gradient curve can improve the validity of edge identification. Finally, the performance of the proposed method has been evaluated using images in a glass flume. The results show that the proposed method for studying the fluid edge is effective and robust. (C) 2017 Elsevier Ltd. All rights reserved.