已入深夜,您辛苦了!由于当前在线用户较少,发布求助请尽量完整地填写文献信息,科研通机器人24小时在线,伴您度过漫漫科研夜!祝你早点完成任务,早点休息,好梦!

Analytical solutions for dispersions and waveforms of acoustic logging in a cased hole

波形 声学 登录中 地质学 计算机科学 物理 电信 地理 雷达 林业
作者
Hua Wang,Tianlin Liu,Yunjia Ji
出处
期刊:Geophysics [Society of Exploration Geophysicists]
卷期号:89 (3): D159-D170
标识
DOI:10.1190/geo2023-0316.1
摘要

Acoustic logging is one of the most promising methods for the quantitative evaluation of cement bond conditions in cased holes. However, inefficient use of full-wave information yields unsatisfactory interpretation accuracy. Fundamentally, this is because the wavefield characteristics have not been thoroughly investigated under various cement bonding conditions. Thus, this study derives analytical solutions of wavefields for a single-cased-hole model and emphasizes the dispersion calculation algorithm. To solve the dispersion equation when solving for the poles of the propagating modes with real wavenumbers, we renormalize the Bessel function related to the borehole fluid by multiplying it with an attenuation factor. For leaky modes with complex wavenumbers, we develop a novel method to find local peaks of the matrix condition number (LPMCN) in the frequency domain to determine dispersion poles, avoiding the local optimization issues resulting from the traditional Gauss-Newton iteration method. Combining these two methods, we establish a fast and accurate workflow for evaluating the dispersion of all modes in cased holes using a relatively fast bisection method to manage the dispersion of the propagating modes and using the LPMCN method to derive the dispersion curves of leaky modes. Furthermore, all propagating modes are individually investigated in the monopole measurement by evaluating the residues of the real poles in a casing-free model. The analysis demonstrates that the first-order pseudo-Rayleigh wave (PR1) and inner Stoneley wave (ST1) are the two strongest modes. Finally, we focus on the waveforms and dispersion characteristics of the outer Stoneley wave (ST2) related to the fluid channel in the cement annulus. The results reveal that as the fluid thickness increases, the phase velocity of the ST2 mode decreases, and its amplitude increases. Therefore, the ST2 mode can potentially evaluate the thickness of the fluid channel in a cement annulus if an effective weak-signal-extraction method is used.
最长约 10秒,即可获得该文献文件

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
PDF的下载单位、IP信息已删除 (2025-6-4)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
刚刚
Lucky.完成签到 ,获得积分0
1秒前
陈陈完成签到,获得积分10
2秒前
3秒前
山鬼谣不会枯死的花完成签到,获得积分10
10秒前
半只熊完成签到 ,获得积分10
14秒前
17秒前
yangcy完成签到 ,获得积分10
18秒前
qinglongtsmc完成签到,获得积分10
19秒前
是小小李哇完成签到 ,获得积分10
24秒前
24秒前
future完成签到 ,获得积分10
25秒前
空白格完成签到 ,获得积分10
31秒前
32秒前
椰小佳完成签到,获得积分20
34秒前
美满的冬卉完成签到 ,获得积分10
35秒前
祁连山的熊猫完成签到 ,获得积分0
36秒前
鸣蜩十三完成签到,获得积分10
36秒前
sl完成签到 ,获得积分10
39秒前
无情妙菡完成签到 ,获得积分10
39秒前
39秒前
40秒前
鸽子爱好者完成签到,获得积分10
41秒前
42秒前
单身的溪流完成签到 ,获得积分10
43秒前
sigrid发布了新的文献求助10
44秒前
45秒前
45秒前
50秒前
一只熊完成签到 ,获得积分10
50秒前
rpe完成签到,获得积分20
51秒前
星辰大海应助鸽子爱好者采纳,获得10
57秒前
nan完成签到,获得积分10
57秒前
柔弱熊猫完成签到 ,获得积分10
58秒前
CC发布了新的文献求助10
59秒前
lh完成签到 ,获得积分10
1分钟前
1分钟前
冷静傲丝完成签到 ,获得积分10
1分钟前
sigrid完成签到,获得积分10
1分钟前
包子完成签到,获得积分10
1分钟前
高分求助中
A new approach to the extrapolation of accelerated life test data 1000
ACSM’s Guidelines for Exercise Testing and Prescription, 12th edition 500
Indomethacinのヒトにおける経皮吸収 400
Phylogenetic study of the order Polydesmida (Myriapoda: Diplopoda) 370
基于可调谐半导体激光吸收光谱技术泄漏气体检测系统的研究 350
Robot-supported joining of reinforcement textiles with one-sided sewing heads 320
Aktuelle Entwicklungen in der linguistischen Forschung 300
热门求助领域 (近24小时)
化学 材料科学 医学 生物 工程类 有机化学 生物化学 物理 内科学 纳米技术 计算机科学 化学工程 复合材料 遗传学 基因 物理化学 催化作用 冶金 细胞生物学 免疫学
热门帖子
关注 科研通微信公众号,转发送积分 3989972
求助须知:如何正确求助?哪些是违规求助? 3532034
关于积分的说明 11256042
捐赠科研通 3270884
什么是DOI,文献DOI怎么找? 1805093
邀请新用户注册赠送积分活动 882256
科研通“疑难数据库(出版商)”最低求助积分说明 809216