Chen Wang, Wu Wanrong, Lu Guoyi, Tian Guangtian
College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China.
National Concrete Machinery Engineering Technology Research Center, ZoomLion, Changsha 410013, China.
Materials (Basel). 2022 Jun 17;15(12):4294. doi: 10.3390/ma15124294.
With an increase of suction efficiency of fresh concrete pumping in confined spaces, the laminar flow state will be damaged by the return flow caused by distribution value direction changes and concrete gravity. This is a fact, but one which is rarely studied. In this work, the flow state, flow velocity, and suction efficiency of fresh concrete pumping are simulated using the coupled smooth particle hydrodynamics and Discrete Elements Method (SPH-DEM). The rheological parameters and Herschel-Bulkley-Papanastasiou (HBP) rheological model are adopted to simulate fresh concrete in the numerical simulation model. The study reveals that the error between the slump experimental result and that obtained by the HBP model is negligible. A model is therefore established for numerical simulations of the suction efficiency of fresh concrete pumping. An experimental concrete pumping platform is built, and the pressure and efficiency data during pumping are collected. A comparison of the numerical simulation with experimental results shows that the error is less than 10%.
随着密闭空间内新拌混凝土泵送吸力效率的提高,层流状态会因分配阀方向变化和混凝土重力引起的回流而受到破坏。这是一个事实,但很少有人对此进行研究。在这项工作中,采用耦合光滑粒子流体动力学和离散元方法(SPH-DEM)对新拌混凝土泵送的流动状态、流速和吸力效率进行了模拟。在数值模拟模型中采用流变参数和赫歇尔-布克利-帕帕纳斯塔西乌(HBP)流变模型来模拟新拌混凝土。研究表明,坍落度试验结果与HBP模型得到的结果之间的误差可以忽略不计。因此建立了一个用于新拌混凝土泵送吸力效率数值模拟的模型。搭建了一个试验性混凝土泵送平台,并收集了泵送过程中的压力和效率数据。数值模拟结果与试验结果的比较表明,误差小于10%。