电动进气格栅控制策略及故障诊断

详细地介绍了电动进气格栅在发动机单独开启、发动机与压缩机同时开启、发动机停机工况下的控制策略和实现方法,给出了具体的电动进气格栅故障诊断方法。     

前扰流板对机舱进气量和车辆气动阻力的影响研究

为研究前扰流板高度变化对发动机舱进气量和整车风阻系数的影响,首先采用CFD软件对整车的基础模型进行气动性能仿真,并与实车风洞试验结果进行对比,确定仿真模型的计算精度;然后在该基础模型上添加不同高度的前扰流板进行仿真。结果显示,在前保险杠下方添加高度合适的前扰流板可有效降低整车风阻系数和提高冷却系统进气量。     

Air Dam对整车气动性能的影响

为进一步提高整车气动性能,降低油耗,通过风洞气动试验,研究了air dam不同安装位置、高度和结构对整车风阻系数和前端进气的影响。结果表明:1在满足整车造型要求的基础上,air dam的安装位置应尽可能前移;2Air dam在拐角处的结构很关键,需要精心设计;3相对于安装位置而言,air dam的高度对前端进气量的影响较大,故在满足路阶和接近角要求的条件下,应尽量取较大值。     

同程式空调水系统的实船设计应用

分析了空调水系统阻力的特点和水力不平衡的原因,并对同程和异程两种空调水系统管路设计方式的优缺点进行了比较。结合某两型船舶的总体布局和空调区域特点,分别采用环形同程冷热媒水系统和开式同程冷却水系统,显著提高了系统水力稳定性,取得较好的空调效果。     

南苏丹朱巴国际机场跑道道面不停航施工改造技术

深入研究了朱巴机场跑道道面现状,分析其道面损坏成因。结合不停航施工要求,针对朱巴机场特殊的气候特征,确定了改造方案,提出不停航施工措施。对沥青混凝土道面进行沥青混凝土罩面改造具有重要借鉴意义。     

海水源变频模块化冷热水机组在船舶中的应用

本文介绍了一种新型海水源变频模块化冷热水机组在某船舶中的应用,也括项目概况、负荷计算过程、机组比选和方案介绍等。并列出了全船空调整系统的原理图。     

浮体横摇运动传递函数数学建模的频域分析研究及相关数值验证(英文)

This paper investigates mathematical modelling of response amplitude operator(RAO) or transfer function using the frequency-based analysis for uncoupled roll motion of a floating body under the influence of small amplitude regular waves. The hydrodynamic coefficients are computed using strip theory formulation by integrating over the length of the floating body. Considering sinusoidal wave with frequency( ω) varying between 0.3 rad/s and 1.2 rad/s acts on beam to the floating body for zero forward speed, analytical expressions of RAO in frequency domain is obtained. Using the normalization procedure and frequency based analysis, group based classifications are obtained and accordingly governing equations are formulated for each case. After applying the fourth order Runge-Kutta method numerical solutions are obtained and relative importance of the hydrodynamic coefficients is analyzed. To illustrate the roll amplitude effects numerical experiments have been carried out for a Panamax container ship under the action of sinusoidal wave with a fixed wave height. The effect of viscous damping on RAO is evaluated and the model is validated using convergence, consistency and stability analysis. This modelling approach could be useful to model floating body dynamics for higher degrees of freedom and to validate the result.     

某水下发射装置自由弯曲振动的流固耦合分析(英文)

A pneumatic launcher is theoretically investigated to study its natural transverse vibration in water. Considering the mass effect of the sealing cover, the launcher is simplified as a uniform cantilever beam with a top point mass. By introducing the boundary and continuity conditions into the motion equation, the natural frequency equation and the mode shape function are derived. An iterative calculation method for added mass is also presented using the velocity potential function to account for the mass effect of the fluid on the launcher. The first 2 order natural frequencies and mode shapes are discussed in external flow fields and both external and internal flow fields. The results show good agreement with both natural frequencies and mode shapes between the theoretical analysis and the FEM studies. Also, the added mass is found to decrease with the increase of the mode shape orders of the launcher.And because of the larger added mass in both the external and internal flow fields than that in only the external flow field, the corresponding natural frequencies of the former are relatively smaller.     

Added resistance acting on hull of a non ballast water ship

In this paper, added resistances acting on a hull of non ballast water ship(NBS) in high waves is discussed. The non ballast water ships were developed at the laboratory of the authors at Osaka Prefecture University, Japan. In the present paper, the performances of three kinds of bow shapes developed for the NBS were theoretically and experimentally investigated to find the best one in high waves. In previous papers, an optimum bow shape for the NBS was developed in calm water and in moderated waves. For a 2 m model for experiments and computations, the wave height is 0.02 m. This means that the wave height is 15% of the draft of the ship in full load conditions. In this paper, added resistances in high waves up to 0.07 m for a 2 m model or 53% of the full load draft are investigated. In such high waves linear wave theories which have been used in the design stage of a ship for a long time may not work well anymore, and experiments are the only effective tool to predict the added resistance in high waves. With the computations for waves, the ship is in a fully captured condition because shorter waves, λ/Lpp0.6, are assumed.     

新型交通工具在交通运输中的应用进展和展望

为了应对快速城镇化发展中的城市交通问题,城市新型交通工具发展迅速。文中综述了国内外11种新型交通工具的关键技术和特性,包括城市轨道交通、地面交通及航空交通,考察新型交通工具在公路、铁路、航空等不同模式下的具体应用,并从资源环境约束、技术经济性能、系统服务性能、产业发展潜力等方面讨论新型交通工具的发展态势。提出多模式一体化综合交通系统发展的关键特征在于共享、畅达、绿色、公平。