Temperature measurement of Ho:YAG laser induced bubble in water using silver halide IR optical fiber

2008 ◽  
Author(s):  
Takehiro Iwasaki ◽  
Eriko Nakatani ◽  
Tsunenori Arai
2000 ◽  
Vol 39 (18) ◽  
pp. 3050 ◽  
Author(s):  
Scott A. Wade ◽  
Stephen F. Collins ◽  
Kenneth T. V. Grattan ◽  
Gregory W. Baxter

2000 ◽  
Author(s):  
S. H. R. Hosseini ◽  
T. Hirano ◽  
O. Onodera ◽  
K. Takayama

Abstract For applying shock waves to precise medical procedures like neurosurgery, a reliable generation of micro shock waves is required. Such sensitive applications make limits on usage of conventional underwater shock wave sources like Extracoporeal Shock Waves ESW [1] or micro explosives [2]. In the present study a Q-switched Ho:YAG laser and an optical fiber are used. Advantages of this method over previous shock wave sources are two order of magnitude reduction in focusing area if compared with ESW and elimination of product gases of micro explosives. Nakahara and Nagayama [3] studied underwater shock waves emanated from surface of an optical fiber by pulse Nd:YAG laser input using shadowgraph technique. Their qualitative study limited to visualization of shock waves at its early stage. The present research aims to clarify quantitatively process of the shock wave generation by direct laser beam irradiation through optical fibers, growth and behavior of generated cavities, and structure of heat induced flow in front of the optical fiber.


Sensor Review ◽  
2021 ◽  
Vol 41 (4) ◽  
pp. 350-360
Author(s):  
Xiao Fang ◽  
Yajie Zeng ◽  
Feng Xiong ◽  
Jiang Chen ◽  
Fei Cheng

Purpose Seepage of the dam is an important safety problem, which may cause internal erosion of the structure. In the field of seepage monitoring in civil engineering, the distributed optical fiber sensing technology based on the temperature tracing method has been paid more attention due to its unique advantages of high sensitivity, good stability and high resolution. The purpose of this paper is to make a review of the existing related research, so as to facilitate the later scholars to understand and further study more systematically. Design/methodology/approach In this paper, three kinds of commonly used distributed fiber temperature measurement technologies are introduced. Based on the working principle, monitoring system, theoretical analysis, experimental research and engineering application of the fiber seepage monitoring technology, the present situation of dam seepage monitoring based on distributed fiber is reviewed in detail and their advantages and disadvantages are compared. Findings The thermal monitoring technology of seepage measurement depends on the accuracy of optical fiber temperature measurement (including the accuracy of the system and the rationality of the discrimination method), the correct installation of optical fiber and the quantitative analysis of temperature data. The accuracy of the current monitoring system can basically meet the existing measurement requirements, but the correct installation of optical fiber and the calibration of temperature data need to be further studied for different discrimination methods, and this field has great research value. Originality/value At present, there are many applications and research studies of optical fiber sensing in the field of structural health monitoring, and there are also reviews of related aspects. However, there is little or no review only in the field of seepage monitoring. This paper summarizes the research and application of optical fiber sensing in the field of seepage monitoring. The possibility of the gradient method to find its new prospect with the development of monitoring systems and the improvement of temperature resolution is discussed. The idea of extending the seepage monitoring method based on distributed optical fiber thermal monitoring technology to other monitoring fields is also given in the paper.


2018 ◽  
Vol 45 (12) ◽  
pp. 1210001
Author(s):  
孟华 Meng Hua ◽  
李海洋 Li Haiyang ◽  
曹占启 Cao Zhanqi

1996 ◽  
Vol 37 (4) ◽  
pp. 912-915 ◽  
Author(s):  
Fumihiko Ogino ◽  
Keisuke Nishimura ◽  
Susumu Okabe ◽  
Etsuji Kimura

Sign in / Sign up

Export Citation Format

Share Document