基于机‑液‑散耦合方法的装载机装卸性能研究

Loader Loading and Unloading Performance Analysis Based on Machine‑Liquid‑Bulk Coupling Method

摘要:

目前装载机研究主要侧重于给定静态载荷下装卸性能，未考虑挖掘过程料堆与机械系统以及液压系统之间的交互作用;针对装载机装卸性能演变分析问题，通过流体仿真和刚散耦合方法研究装载机装卸性能不能反映装卸过程物料系统、机械系统以及液压系统之间的实时交互效应。为此，本文以阀控装载机为例，基于机?液?散耦合方法构建了装载机装卸性能模型，探究了装载机在不同复合动作下装卸性能。结果表明：变举升液压阀开度工况下液压泵峰值功率高于变转斗液压阀开度工况的液压泵峰值功率，并且随着举升液压阀开度增加，物料扰动速度先稳定后有所下降，随着转斗液压阀开度增加，物料扰动速度先增加后下降。研究结果可为装载机数字化设计提供借鉴。

Abstract:

As a piece of key mechanical equipment in agriculture and construction, the performance improvement of loaders is of great significance. The current study mainly focused on the loading and unloading performance of loaders under a given static load, without considering the interaction between the material system, the mechanical system, and the hydraulic system in the excavation process. The loading and unloading performance of the loader was mainly investigated by the fluid simulation and rigid?diffusive coupling methods, which were not able to reflect the real?time interaction between the material system, the mechanical system, and the hydraulic system in the loading and unloading process. For this reason, a loading and unloading performance model of the working device of the widely used valve?controlled loader was constructed based on the machine?liquid?bulk multi?coupling method, on this basis, the loading and unloading performance evolution law of the loader under different composite actions was investigated. The results showed that the lifting hydraulic cylinder rodless chamber pressure was about 8 MPa, the bucket hydraulic cylinder rodless chamber pressure was about 4 MPa, and the bucket hydraulic cylinder rodless chamber pressure was more stable than the lifting hydraulic cylinder rodless chamber pressure under steady state operation. When the opening degree of both the lift hydraulic valve and the bucket hydraulic valve was 62.5%, the full bucket rate of the loader reached 91.48%, and the lift action had obvious influence on the digging volume of the loader. The peak power of the hydraulic pump under the variable lifting hydraulic valve opening condition was higher than that under the variable dumping bucket hydraulic valve opening condition, and the material disturbance velocity was first stabilised and then decreased with the increase of lifting hydraulic valve opening, and increased and then decreased with the increase of dumping bucket hydraulic valve opening. The research findings may serve as a reference for the digital design of loaders.