链履式滩涂贝类养殖行走装置设计与试验

Design and Test of Chain-track Shellfish Aquaculture Walking Device in Tidal Flat

摘要:

针对潮间带滩涂底播养殖区域地质松软、承载力低,行走机械易出现牵引力不足及滑转等问题,提出一种适用于淤泥质滩涂的链履式行走装置。该装置采用双节距特种链条布设于浮箱车体两侧,通过履带板剪切土壤产生推力,并依托滚子实现车体平稳移动。通过理论分析确定影响牵引性能的关键结构参数,并构建三节链履与黏塑性滩涂土壤的离散元仿真模型,开展履带板推土仿真分析。以履带板宽度、履带板高度、履齿拔模角及履带板节距为试验因素,以沉陷量、牵引系数为评价指标,进行单因素试验,得到影响牵引性能的主要因素为履带板宽度、履带板高度、履带板节距。以此为试验因素,进行三因素三水平中心组合试验,以低沉陷量、高牵引系数为目标对各试验因素进行优化,得到链履结构的最优参数组合为:履带板宽度700mm,履带板高度118mm,履带板节距203mm。采用优化后的参数研制样机进行滩涂行驶试验,结果表明,在1000kg负载状态下,该装置直线行驶滑转率为32.33% ,与仿真结果对比,二者绝对误差仅为7.66个百分点。研究表明该行走装置能有效适应滩涂环境,为开发工作效率更高的滩涂运载设备奠定基础。

Abstract:

Aiming at the problems of soft geology, low bearing capacity, insufficient traction and easy slippage of walking machinery in the bottom sowing and breeding area of intertidal mudflats, a chain-crawler walking device suitable for muddy tidal flats was proposed. The device used a double-pitch special chain arranged on both sides of the pontoon body, generated thrust by shearing soil with the track shoes, and realized smooth movement of the body relying on rollers. The key structural parameters affecting traction performance were determined through theoretical analysis. A discrete element simulation model of a three-link chain-crawler and viscoplastic tidal flat soil was established to conduct bulldozing simulation analysis of the track shoes. Taking track shoe width, track shoe height, track tooth draft angle and track shoe pitch as test factors, and settlement and traction coefficient as evaluation indexes, single-factor tests were carried out. The main factors influencing traction performance were identified as track shoe width, track shoe height and track shoe pitch. On this basis, a three-factor, three-level central composite design experiment was conducted. The test factors were optimized with the objectives of low settlement and high traction coefficient. The optimal parameter combination of the chain-crawler structure was obtained as follows: track shoe width was 700mm, track shoe height was 118mm, track shoe pitch was 203mm. A prototype was manufactured by using the optimized parameters and subjected to tidal flat driving tests. The results showed that under a 1000kg load, the straight driving slip rate of the device was 32.33%, compared with the simulation results, the absolute error between the two is 7.66 percentage points. The research result demonstrated that the walking device can effectively adapt to the tidal flat environment, laying a foundation for the development of higher efficiency tidal flat carrying equipment.