Abstract
As a new type of submarine pipeline, the piggyback pipeline has been gradually adopted in engineering practice to enhance the performance and safety of submarine pipelines. However, limited simulation work and few experimental studies have been published on the scour around the piggyback pipeline under steady current. This study numerically and experimentally investigates the local scour of the piggyback pipe under steady current. The influence of prominent factors such as pipe diameter, inflow Reynolds number, and gap between the main and small pipes, on the maximum scour depth have been examined and discussed in detail. Furthermore, one formula to predict the maximum scour depth under the piggyback pipeline has been derived based on the theoretical analysis of scour equilibrium. The feasibility of the proposed formula has been effectively calibrated by both experimental data and numerical results. The findings drawn from this study are instructive in the future design and application of the piggyback pipeline.
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Acknowledgements
This study is financially supported by the National Key Research and Development Program of China (No. 2017 YFC1404700), the National Natural Science Foundation of China (Nos. 51279189, 51239001 and 51509023) and the China Scholarship Council. The authors are grateful to the anonymous reviewers for their valuable suggestions to improve the quality of this manuscript.
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Zhao, E., Shi, B., Qu, K. et al. Experimental and Numerical Investigation of Local Scour Around Submarine Piggyback Pipeline Under Steady Current. J. Ocean Univ. China 17, 244–256 (2018). https://doi.org/10.1007/s11802-018-3290-7
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DOI: https://doi.org/10.1007/s11802-018-3290-7