Developing a Computer Program for Detailed Study of Planing Hull＇s Spray Based on Morabito＇s Approach

Recently, Morabito （2010） has studied the water spray phenomena in planing hulls and presented new analytical equations. However, these equations have not been used for detailed parametric studies of water spray around planing hulls. In this paper, a straight forward analysis is conducted to apply these analytical equations for finding the spray geometry profile by developing a computer program based on presented computational process. The obtained results of the developed computer program are compared against existing data in the literature and favorable accuracy is achieved. Parametric studies have been conducted for different physical parameters. Positions of spray apex are computed and three dimensional profiles of spray are examined. It is concluded that spray height increases by an increase in the speed coefficient or the deadrise angle. Ultimately, a computational process is added to Savitsky＇s method and variations of spray apex are computed for different velocities. It is shown that vertical, lateral, and longitudinal positions of spray increase as the craft speed increases. On the other hand, two new angles are defined in top view and it is concluded that they have direct relation with the trim angle. However, they show inverse relation with the deadrise angle.     

邂逅惊喜 斯柯达Yeti 4×4

短小精悍,是斯柯达Yeti给人的第一印象。短轴距、大功率、四轮驱动,与生俱来的优势让斯柯达Yeti有着一种桀骜不驯的气质。这也让此次"越趣之行,大美赤峰"的活动多了一份期待,大家似乎都想让斯柯达Yeti能带来更多的惊喜。     

西南山区陡坡高路堤稳定性分析

在山区道路建设中，不可避免会遇到大量的陡坡高路堤，针对其破坏模式，合理选取潜在滑动面抗剪强度参数，是陡坡高路堤稳定性分析的关键。以重庆市巴南区某主干路K0+480～+680段陡坡高路堤为例，探讨山区陡坡高路堤破坏模式、潜在滑动面抗剪强度参数取值及稳定性分析。     

大荷载矿石堆场中深厚吹填软土的地基处理及后评价

吹填淤泥形成陆域是资源利用和环境保护方面的优质解决方案,但当前吹填软土形成陆域的工程中,多数为荷载较小的堆场、工业园区道路、绿化区等。以青岛港董家口港区矿石码头工程20万吨级散货泊位后方预留堆场区的地基处理工程为例,对该工程的设计、施工及使用后6年的情况进行详细阐述,从多个角度展示深厚吹填软土的演变情况,详细介绍土体含水量、孔隙比、抗剪强度等指标在不同时期的变化,对比施工期沉降计算和监测数据,分析不同时期抗剪强度指标下矿石堆存的高度。结果表明,在大荷载矿石堆场中采用吹填软土形成陆域是可行的,通过合理的地基处理方式和有序增加堆存荷载,最终可使矿石堆场达到满载堆存。     

高速铁路挡风墙高度和距离优化分析

为探讨挡风墙对列车横向气动性能的影响,基于可压缩粘性流体Navier-Stokes方程和k-两方程湍流模型,采用有限体积法,计算了列车在直线和不同半径曲线线路上运行时,不同挡风墙高度和距离的275种工况下列车侧向力和侧翻力矩,获得了最佳挡风墙高度和距离.研究结果表明:在列车速度为200~400 km/h,风速为20~40 m/s的条件下,列车在直线线路上运行的最佳挡风墙高度和距离分别约为1.90和3.90 m;当弯道半径为1 000~7 000 m时,曲线线路最佳挡风墙高度随弯道半径增大线性减小,最佳挡风墙距离与弯道半径关系不大,约4.50 m;风速和列车速度对挡风墙的最佳高度和最优距离影响很小;如果挡风墙高度过低或距离过近,头车和尾车所受侧向力和侧翻力矩方向不同.      

世界最大海上作业浮式起重机交付

11月8日,由中交集团所属上海振华重工自主设计研发的目前世界上最大的海上作业浮式起重机——8000吨浮式起重机,在上海长兴岛成功交付韩国三星重工。该浮式起重机为双臂、双塔(人字架)、八钩巨型浮吊,最大起重量为8000t,起升高度达水面上120m,吊载8000t时最大幅度可达舷外57m,可用于船舶分段、海上平台模块等大型构件的运输及安装。该浮式起