基于计算流体动力学(CFD)方法建立数值波浪水池,对顶浪中航行船舶的水动力与运动进行数值计算研究。推导出一种船舶在波浪中航行的数值模拟的波浪环境表达方法并进行模拟验证,计算不同航速下顶浪中Wigley-III船模所受的水动作用力,以及顶浪中航行的Wigley-III船模的运动。通过将计算结果与DUT(Delft University of Technology)相关的试验数据进行比较,吻合良好。研究表明:基于数值波浪水池的数值模拟较试验更容易实现和控制,能够获得船体周围详细的流场信息,在波浪中舰船水动力性能与运动的研究等方面具有广泛的适用性。
To understand the mooring energy during Fositioning, the expressions of four items concerning mooring line energy are presented based on a finite element model, including gravitational and elastic potential energy, kinetic energy and dissipated energy due to mooting-induced damping. In a static case, the force calculated from the derivative of potential energy with respect to distance is compared with that of direct calculation. The results are tbund fit well, which indicates the law of conservation of energy and also shows the correctness of the potential energy results. For the cases of a single mooring line with the attaclunent point oscillating with different amplitudes in horizontal or vertical direction （corresponding to surge and roll motions respectively）, and the case of the mooring line with a horizontal bicbromatic oscillation on the attachment point, the time history of the first three items are calculated and analyzed, also, the indicator diagram tbr mooring-induced damping are given. These results reveal the energy state of the mooring line and can provide a better understanding of how the mooring line works.
A multi-body coupled dynamic model is developed （TROV） system. A strong nonlinear coupling motion between to simulate the motion of a Tethered Remotely Operated Vehicle umbilical tether and ROV is discussed .The movement of ROV is considered as six-degrees of freedom. The lumped mass model is applied and an averaged tangential vector technique is included in the three-dimensional dynamic response equations of the cable-segments. The model can simulate the three-dimensional transient coupled motion of the complex multi-body system in typical ship maneuvering conditions and can be used in either a towing problem or a tethered underwater vehicle problem. Simulation results are seen to fit well with the experiment.
基于CFD方法建立了数值波浪水池,模拟了规则波浪的生成传播,并对顶浪中航行船舶的运动进行了模拟计算研究。讨论了数值模拟中的波浪环境表达,验证了数值波浪水池中波浪的生成、传播与消波等,模拟计算了多个航速顶浪中航行Wigley-III船模的运动与波浪增阻。将计算结果与DUT(Delft University of Technology)的试验数据相比较,吻合良好。对比和研究表明,基于数值水池的数值模拟方法比试验更易实现和控制,能细致描述船舶周围的流场,在波浪中舰船水动力性能的分析与运动预报等方面具有广阔的应用前景。
