The Numerical Modeling of the Signal Transmission by the Cables and the Coil Coupling for LWD

Abstract:

Lack of efficiency in transmitting logging signals from down-hole to the top-hole server has long been one of the crucial problems for the development of LWD. This study aims to address this issue by exploring into the advanced scheme for LWD signal transmission proposed by NovatekTM. The main focus of the study is on electromagnetic coupling between two adjacent pipes. The coupler is modeled numerically by NMM efficiently according to the axial symmetry of the coupler. Through simulation and analysis which are based on the numerical model of the coupler, various parameters of the coupler are discussed, and some significant conclusions are obtained. The conclusions can guide optimization design of the coupler between the drill-pipes for signal transmission in LWD. Furthermore, the experimental results verify the good transmission performance of the coupler which is designed in this paper.

• Periodical: Advanced Materials Research (Volumes 588-589)
• Pages: 416-419
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.588-589.416
• Online since: November 2012
• Authors: Ke Bin Zhu, Zai Ping Nie, Xiang Yang Sun
• Keywords: Electromagnetic Coupling, Logging while Drilling (LWD), Numerical Mode Matching (NMM), Signal Transmission

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