共查询到20条相似文献,搜索用时 84 毫秒
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煤矿透水事故时有发生,现有抢险泵难以快速下井排水。为实现快速救援目标,提出一种新型体积小、流量大和扬程高的矿用高速抢险泵。机组设计采用上机下泵、机泵一体、独立冷却润滑回路、高速推力轴承机构以及水仓湿定子潜水电动机密封等关键技术。在同等流量、扬程的情况下,和现有产品相比,设计开发的矿用高速抢险泵在长度上减少了31%,重量减少了51.2%。以GFQ200-300型样机为例,通过数值模拟计算方法得出矿用高速抢险泵在6 000r/min下,不同叶轮和导叶叶片数匹配模式下,最大扬程为304.56m,最高效率为64.32%。样机试验结果表明:矿用高速抢险泵结构和水力设计合理,满足性能要求;数值模拟计算方法准确可靠,且采用SST k-ω模型最为贴近试验结果。样机整体机组结构和水力模型方案为后续大功率高速泵机组的设计提供了重要理论指导和技术积累。 相似文献
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目前国内大部分微型泵都是进口国外的,微型泵的设计技术被垄断,为了解决工程机械、海洋船舶、航空航天、医疗等行业的需求,设计了一种微型大排量的等宽曲线泵.依据莱洛三角形在等边正方形内旋转运动时,每时刻都有四个位置与正方形相交且交点不断变化原理,分析运动过程轨迹,设计出了行星轮传动机构,并应用ADMAS软件创建模型分析机构运... 相似文献
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随着流体机械理论、计算机技术和数控加工技术的发展,泵叶轮的研发技术正在从传统的"相似设计-试制-试验-改进"的低效率反复手工过程向全过程的数值优化设计过渡,但在数值研发叶轮的过程中,由于受到水力设计理论、高精度高分辨率叶轮流场计算、叶轮造型与流场结构之间的影响规律及叶轮优化设计方法等诸多因素的制约,要想真正实现高性能泵叶轮完全数值研发的目标,还需要逐一深入探讨这些关键因素,为将来最终解决其中的基础理论问题提供必要指导。 相似文献
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为了提高环形射流泵的输送效率,本文提出了一种利用导叶结构形成螺旋流的螺旋流环形射流泵。利用数值模拟的方法研究不同工作压力下的螺旋流环形射流泵和原型泵的速度、压力和湍动能分布计算结果,来分析螺旋流对环形射流泵的性能影响。数值模拟结果表明:在工作压力为130 kPa时,螺旋流使环形射流泵的流量比增加了43.1%,压力比降低了22.8%。螺旋流降低了环形射流泵喉管内的静压,更容易引起空化。螺旋流使得环形射流泵的效率在工作压力低于160 kPa时大于原型泵。螺旋流环形射流泵内具有更大的湍动能分布区域。随着工作压力升高,两种结构的环形射流泵湍动能分布差别减小。导叶阻力对螺旋流环形射流泵的效率有着重要的影响。 相似文献
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提出了在较小流量的切线泵中运用加大流量的设计方法,并从理论和实践上证明了采用这种方法可以使效率得到明显提高。阐述了部分流泵加大流量设计方法的特点。 相似文献
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通过数值模拟,对某单级轴流风机内的流动进行分析,计算结果表明:随着预旋角的增大,静压、全压、轴功率以及效率都随之减小。在负预旋情况下,叶顶前缘处存在明显的低压区。吸力面的分离对预旋角变化敏感。随着预旋角的减小,流场的非定常性也增强,分离尺度增强。 相似文献
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During the process of designing the mixed-flow pump impeller, the meridional flow passage shape directly affects the obtained meridional flow field, which then has an influence on the three-dimensional impeller shape. However, the meridional flow passage shape is too complicated to be described by a simple formula for now. Therefore, reasonable parameter selection for the meridional flow passage is essential to the investigation. In order to explore the effects of the meridional flow passage shape on the impeller design and the hydraulic performance of the mixed-flow pump, the hub and shroud radius ratio (HSRR) of impeller and the outlet diffusion angle (ODA) of outlet zone are selected as the meridional flow passage parameters. 25 mixed-flow pump impellers, with specific speed of 496 under the design condition, are designed with various parameter combinations. Among these impellers, one with HSRR of 1.94 and ODA of 90° is selected to carry out the model test and the obtained experimental results are used to verify accuracies of the head and the hydraulic efficiency predicted by numerical simulation. Based on SIMPLE algorithm and standard k-ε two-equation turbulence model, the three-dimensional steady incompressible Reynolds averaged Navier-Stokes equations are solved and the effects of different parameters on hydraulic performance of mixed-flow pump impellers are analyzed. The analysis results demonstrate that there are optimal values of HSRR and ODA available, so the hydraulic performance and the internal flow of mixed-flow pumps can be improved by selecting appropriate values for the meridional flow passage parameters. The research on these two parameters, HSRR and ODA, has further illustrated influences of the meridional flow passage shape on the hydraulic performance of the mixed-flow pump, and is beneficial to improving the design of the mixed-flow pump impeller. 相似文献
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Numerical simulation and analysis of solid-liquid two-phase flow in centrifugal pump 总被引:5,自引:2,他引:5
The flow with solid-liquid two-phase media inside centrifugal pumps is very complicated and the relevant method for the hydraulic design is still immature so far.There exist two main problems in the operation of the two-phase flow pumps,i.e.,low overall efficiency and severe abrasion.In this study,the three-dimensional,steady,incompressible,and turbulent solid-liquid two-phase flows in a low-specific-speed centrifugal pump are numerically simulated and analyzed by using a computational fluid dynamics(CFD) code based on the mixture model of the two-phase flow and the RNG k-two-equation turbulence model,in which the influences of rotation and curvature are fully taken into account.The coupling between impeller and volute is implemented by means of the frozen rotor method.The simulation results predicted indicate that the solid phase properties in two-phase flow,especially the concentration,the particle diameter and the density,have strong effects on the hydraulic performance of the pump.Both the pump head and the efficiency are reduced with increasing particle diameter or concentration.However,the effect of particle density on the performance is relatively minor.An obvious jet-wake flow structure is presented near the volute tongue and becomes more remarkable with increasing solid phase concentration.The suction side of the blade is subject to much more severe abrasion than the pressure side.The obtained results preliminarily reveal the characteristics of solid-liquid two-phase flow in the centrifugal pump,and are helpful for improvement and empirical correction in the hydraulic design of centrifugal pumps. 相似文献
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Driving a hydraulic cylinder directly by a closed-loop hydraulic pump is currently a key research area in the field of electro-hydraulic control technology,and it is the most direct means to improve the energy efficiency of an electro-hydraulic control system.So far,this technology has been well applied to the pump-controlled symmetric hydraulic cylinder.However,for the differential cylinder that is widely used in hydraulic technology,satisfactory results have not yet been achieved,due to the asymmetric flow constraint.Therefore,based on the principle of the asymmetric valve controlled asymmetric cylinder in valve controlled cylinder technology,an innovative idea for an asymmetric pump controlled asymmetric cylinder is put forward to address this problem.The scheme proposes to transform the oil suction window of the existing axial piston pump into two series windows.When in use,one window is connected to the rod chamber of the hydraulic cylinder and the other is linked with a low-pressure oil tank.This allows the differential cylinders to be directly controlled by changing the displacement or rotation speed of the pumps.Compared with the loop principle of offsetting the area difference of the differential cylinder through hydraulic valve using existing technology,this method may simplify the circuits and increase the energy efficiency of the system.With the software SimulationX,a hydraulic pump simulation model is set up,which examines the movement characteristics of an individual piston and the compressibility of oil,as well as the flow distribution area as it changes with the rotation angle.The pump structure parameters,especially the size of the unloading groove of the valve plate,are determined through digital simulation.All of the components of the series arranged three distribution-window axial piston pump are designed,based on the simulation analysis of the flow pulse characteristics of the pump,and then the prototype pump is made.The basic characteristics,such as the pressure,flow and noise of the pumps under different rotation speeds,are measured on the test bench.The test results verify the correctness of the principle.The proposed research lays a theoretical foundation for the further development of a new pump-controlled cylinder system. 相似文献
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轴向柱塞泵平面配流副的优化设计模型研究李小宁毕诸明路建萍(南京理工大学制造工程学院210094)1引言轴向柱塞泵平面配流副是指由泵缸体与配流盘组成的转动摩擦副。在工作时,配流副之间的高压液体对缸体产生必要的反推力和反推力矩,以平衡柱塞对缸体产生的压紧... 相似文献
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运用三维粘性流动计算软件,对某含叶顶间隙的直叶片轴流风扇进行数值模拟。叶顶间隙按相对间隙进行取值,其大小分别为0、0.5%、1.0%、1.5%和2.0%,其它计算参数不变。通过对计算结果的对比分析,研究叶顶间隙变化对总体性能的影响。结果表明,叶顶间隙变化对轴流风扇性能有较大影响,随着叶顶间隙的增大,其效率、全压减小。 相似文献