Abstract: To address the technical bottlenecks such as large data volume and limited transmission bandwidth encountered in constructing a high-fidelity digital twin of a liquefied natural gas (LNG) carrier, this paper proposes a ship-to-shore data transmission system that integrates reliable transmission and efficient compression. First, the system uses standardized interfaces to achieve multi-source data acquisition, and through a data hierarchical transmission strategy, extracts the value of the data. On this basis, the GZip algorithm is introduced to efficiently compress key data such as those from the liquid cargo tank system. Second, based on the data transmission architecture of the Message Queuing Telemetry Transport (MQTT) protocol, a quality of service (QoS) level confirmation mechanism is introduced to ensure effective data transmission, and an intelligent network disconnection recovery strategy is proposed to enable local caching at the ship end and ensure complete data transmission. Finally, real ship application verification shows that the proposed system achieves a compression rate of over 93% while ensuring 100% complete data transmission, and significantly reduces the end-to-end transmission delay under limited bandwidth. This study comprehensively improves the effectiveness of data transmission for the digital twin of LNG carriers from three dimensions—transmission efficiency, reliability, and real-time performance—and verifies the effectiveness of the proposed transmission strategy and modules, laying the foundation for the engineering application of high-value ship digital twin systems.

Key words: liquefied natural gas (LNG) carrier, digital twin, ship-to-shore data transmission, GZip compression algorithm, message queuing telemetry transport (MQTT) protocol

摘要： 针对高保真液化天然气（liquefied natural gas,LNG）运输船数字孪生体构建中所面临的数据体量大、传输带宽受限等技术瓶颈,文章提出一套集成可靠传输与高效压缩的船岸数据回传系统。首先,该系统使用标准化接口实现多源数据采集,通过数据分级回传策略提炼其价值,并引入GZip算法对液货舱系统等关键数据进行高效压缩。其次,该系统基于消息队列遥测传输协议的数据回传架构,通过引入服务质量等级确认机制,提出智能断网续传策略以实现船端本地缓存、确保数据完整传输。最终,经实船应用验证,该系统在确保数据100%完整回传的前提下,实现了超过93%的压缩率,并在受限带宽下显著降低了端到端回传时延。该研究从传输效率、可靠性与实时性这3个 维度全面提升了LNG运输船数字孪生体数据回传的有效性,验证了所提传输策略与模块的合理性,为高价值船舶数字孪生系统的工程化应用奠定了基础。

关键词: 液化天然气运输船, 数字孪生, 船岸数据回传, GZip算法, MQTT协议