摘要：In the case of the given design variables and constraint functions, this paper is concerned with the rapid overall parameters design of trajectory, propulsion and aerodynamics for long-range ballistic missiles based on the index of the minimum take-off *** contrast to the traditional subsystem independent design, this paper adopts the research idea of the combination of the subsystem independent design and the multisystem integration ***, the trajectory, propulsion and aerodynamics of the subsystem are separately designed by the engineering design, including the design of the minimum energy trajectory, the computation of propulsion system parameters, and the calculation of aerodynamic coefficient and dynamic derivative of the missile by employing the software of missile DATCOM. Then, the uniform design method is used to simplify the constraint conditions and the design variables through the integration design, and the accurate design of the optimized variables would be accomplished by adopting the uniform particle swarm optimization(PSO) algorithm. Finally, the automation design software is written for the three-stage solid ballistic missile. The take-off mass of 29 850 kg is derived by the subsystem independent design, and 20 constraints are reduced by employing the uniform design on the basis of 29 design variables and 32 constraints, and the take-off mass is dropped by 1 850 kg by applying the combination of the uniform design and PSO. The simulation results demonstrate the effectiveness and feasibility of the proposed hybrid optimization technique.

摘要：《水土保持规划编制规范》(SL/T 335—2024)经水利部2024年第19号公告发布,于2024年11月24日正式实施。此次修订是在系统总结原标准执行情况的基础上,根据新形势和新要求,以存在的问题和需求为导向,衔接协调相关规划编制要求,经过充分讨论、广泛征求意见和咨询专家后系统开展的。修订后进一步明确了水土保持规划分类,优化了标准框架结构,深化细化了标准内容。修订后的标准对规范新时期水土保持规划编制工作具有重要意义,将进一步健全全国水土保持规划体系,推动水土保持高质量发展。

摘要：Very high flow coefficient centrifugal compressor stages are mostly performance of this type of stages is critical to the entire centrifugal applied as the first stages of multistage compressors. The compressors, but surprisingly little related information is available in the open literature. A centrifugal compressor with high inlet flow coefficient of 0.2, presenting a narrow operating range and unstable running situation even at design speed during the test, is investigated here. To reveal flow details in this centrifugal compressor, numerical simulations have been carried out and indicate that excessive impeller flow diffusion results in the poor performance of this centrifugal compressor. With the same inlet flow coefficient, six redesign cases coming from an in-house one-dimensional analysis program are proposed together with impeller trimming and equal flow area design method for corresponding vaneless diffuser. Performance comparison among these redesign centrifugal compressors is presented and the most suitable one is recommended for test in the future. In addition, three redesign cases with lower inlet flow coefficient developed by means of flow trimming are shown in the end to satisfy potential application areas. Finally, the results in this study can provide valuable reference information for multistage centrifugal compressor design.

摘要：为了快速、准确地设计出高质量喷水推进泵,采用三元反问题计算与正问题计算相互迭代的方法对某混流式喷水推进泵进行了设计.基于三元的方法对喷水推进泵叶轮进行设计,把叶轮内的三维流动分解为周向平均流动和周向脉动流动,周向平均流动方程直接由三维Euler方程作周向平均导出,周向脉动流动由Clebsch变换建立起控制方程;用置于叶片中心面上的涡来代替叶片对流场的作用,而叶片形状以满足流动边界条件迭代确定.用考虑流体粘性的雷诺时均方法(RANS)对所设计泵进行数值试验,计算结果表明:所设计泵在设计点效率达到90.5%,设计转速下喷泵NPSHr远小于设计指标,并且在较宽的流量范围内具有良好的水力性能,验证了设计方法的准确性和有效性.

摘要：为了设计浸没式喷水推进泵,以国外某喷水推进混流泵为对象建立了浸没式喷射模型,运用计算流体力学(CFD)瞬态模拟方法研究了2种转速时浸没式喷射对喷水推进泵水力性能的影响。研究表明,无论是低转速还是设计转速,浸没式喷射时喷水推进泵的扬程、轴功率、效率变化都小于1%,且叶片的空化无明显变化。由此,运用三元设计方法设计了一型适用于常规尾板式喷水推进的喷水推进泵,即按常规尾板式喷水推进的"船-泵-机"匹配方法选定喷水推进泵的设计参数,按基于环量的三元方法进行喷泵的水力设计,喷泵为6片叶片、9片导叶。最后,运用计算流体力学方法对实尺浸没式喷水推进器与船体的组合结构进行了数值模拟,结果表明,在设计航速时,该喷水推进泵完全浸没在水中工作的水力性能变化很小,进而得出浸没式喷水推进泵可以按照常规尾板式喷水推进泵的设计方法进行设计的结论。

摘要：为了提高喷水推进器进水流道的设计水平,改善其水动力性能、缩短设计周期、降低设计费用,研究了进水流道的参数化设计方法.在该方法中,进水流道的三维几何结构采用11个动态关联的控制参数定量描述.改变这些控制参数的值可自动调整流道的三维空间形状,实现流道几何的快速建模.在此基础上,利用计算流体力学方法对进水流道及船尾流场进行数值计算,用进水流道的出流均匀度、流动分离程度、空化程度、流动损失程度以及变工况适用性等多项指标对进水流道的流体动力性能进行综合评估.流道三维几何结构的参数化建模和综合流体动力性能的数值模拟这2个过程迭代运用,可实现进水流道的优质、快速设计.

摘要：运用泵的三元设计理论和计算流体力学（CFD）数值计算方法对大功率、高效率轴流式喷水推进泵进行水力设计和性能预报，并对喷口轴向长度、叶轮叶片随边与导叶叶片导边的轴向距离以及叶顶间隙对喷泵水力性能的影响进行进一步计算与分析。从理论上说明叶轮叶片和导叶叶片之间存在最佳匹配距离，该最佳间距为标称直径的3%~4%。运用黏性雷诺时均方法（RANS）对所设计轴流式喷泵水力性能进行数值预报。研究结果表明：泵在设计流量点效率达到92.3%，同时也满足抗空化性能要求，且在较宽的流量范围内具有良好的水力性能。

摘要：基于Matlab-Simulink建立了一套轴流式喷水推进泵计算机辅助设计(CAD)程序(其中叶轮采用升力法设计,导叶采用流线法设计),实现了其水力设计参数的快速选择与计算,直接得到了叶片流面的空间坐标,可方便进行三维几何造型.采用计算流体力学(CFD)方法,通过建立计算域、划分高质量结构化网格、定义边界条件、数值计算和后处理等步骤详细分析了所设计轴流式喷水推进泵内流场分布,并对扬程、效率等水力性能进行综合检验.通过实例详细阐述了轴流式喷水推进泵CAD设计和CFD水力性能预报的各个环节,结果表明该方法可快速、高效、优质的完成轴流式喷水推进泵的水力设计、性能评估和结构优化,对加速喷水推进泵的研发和促进喷水推进在国内应用具有积极意义.

摘要：[目的]针对国内外喷水推进和泵喷推进的概念缺乏完整定义、外延尚存混淆、产品称谓混乱的现状,[方法]通过对这2种推进器工作原理和具体结构的剖析,进行共性提炼和特性区分,提出喷水推进和泵喷推进的定义,指出它们的共性、特性及区别。[结果]喷水推进和泵喷推进均属泵类推进,都是通过管道内叶轮和导叶的流场匹配设计在喷口产生轴向射流而获得推进作用;喷水推进的第一设计指标是高效率、首要保证快速性,相应的设计结果是喷水推进器;泵喷推进的第一设计指标是低噪声、首要保证声隐身性,相应的设计结果是泵喷推进器。[结论]该定义不仅包含和区分了已问世至今的喷水推进器和泵喷推进器,而且也明示了国外某些泵类推进器命名存在的问题。该定义有助于业内对喷水推进和泵喷推进的认识和区分。

摘要：为将某滑行艇螺旋浆替换为泵喷推进器,本文采用三维反问题方法执行泵喷的转子和静子设计,泵喷导管采用改进的导管桨19A导管,叶片厚度分布依据NACA翼型规律分布。在验证CFD数值模拟可信性的前提下对泵喷和螺旋桨进行了敞水计算和水力特性对比。结果显示:基于同一主机,在各自设计工况下所设计前漩式泵喷对应航速更高,喷水能量的轴向分量高出原桨2.5%,推进效率高出原桨3.3%,高速适应性更强,验证了设计方法的准确性和有效性。