Due to high power consumption and low energy efficiency of the hydrogenation feed multistage pump, conducting structural optimization design and reducing energy losses for this pump is necessary. In this study, an optimization method based on the particle swarm optimization (PSO) algorithm and least squares support vector regression (LSSVR) surrogate model is proposed. The head and efficiency are taken as the optimization objectives of the multistage pump, and the optimization design of the two impellers is carried out. Through the optimization of the surrogate model, the head and efficiency of the multistage pump are increased by 3.99% and 2.91%, respectively. It is found that the optimized impeller has more stable flow characteristics than original impeller. Further, the entropy production method is introduced to analyze the energy loss of pump. The result shows that the pump optimized by PSO-LSSVR surrogate model can reduce 9% energy consumption under nominal flow rate. It is attributed to the inhibitory effect of the optimization scheme on the horseshoe vortex at leading edge and the wake vortex at trailing edge of impeller. This study provides a new idea for the optimization design of high efficiency and low energy consumption of multistage centrifugal pumps.

因急冷油中含有固体颗粒,在运行过程中会对泵的过流部件造成磨损,从而影响泵的寿命.基于离散模型(DPM),针对不同粒径、不同浓度的颗粒对叶轮的磨损进行了数值模拟分析.研究结果表明:颗粒粒径保持不变时,随着颗粒质量浓度的增大,急冷油泵过流部件上的磨损位置不变,磨损量增加;颗粒质量浓度保持不变,当粒径从0.025 mm增加到2 mm时,叶片工作面尾缘磨损程度加剧,背面磨损程度降低,前盖板靠近背面一侧磨损减弱,靠近工作面一侧磨损加剧;颗粒粒径与颗粒浓度不变的情况下,通过优化叶片的出口角度,可以适当降低整体的磨损率,达到优化作用.

针对加氢进料多级泵的高功耗和低能效的情况,有必要对该泵进行结构优化设计并减少能量损失,引入机器学习,建立了支持向量回归(SVM)代理模型,并采用粒子群优化算法(PSO)解决最小二乘支持向量回归(LSSVR)代理模型的超参数确定问题.以HDB型多级离心泵为研究对象,对首级双吸叶轮与次级单吸叶轮的叶片数、进出口角、包角以及出口宽度同时进行了优化,并对优化结果进行了响应分析;用数学性能指标评估了代理模型的精度,通过数值模拟对比了优化前后模型泵的性能.结果表明,PSO-LSSVR代理模型精度高,可以用来预测离心泵的外特性并优化,优化后多级泵的扬程和效率分别提高了3.99%和2.91%,优化后的内部流场更加稳定,更有利于流体的能量转换.

某石化厂乙二醇装置反应器进料泵开车不久出现泵内异响、振动变大现象,停机解体后发现叶轮破损严重.通过失效分析和ANSYS结构分析,确认叶轮破损原因为叶轮盖板强度不足、铸件材料存在疏松和夹杂物.经研究分析,改进措施为适当加厚叶轮盖板并严格控制材料成分,制造新叶轮并在用户现场正常开车运行,改进的成功对发生该类问题泵的设计、制造和检维修具有一定的借鉴意义.

Cavitating flows in fluid machineries always present complicated phase morphologies including a wide range of interface length scales. In the present work, an Eulerian-Lagrangian cavitation model is proposed for simulating the unsteady cavitating flow and investigating the multiscale cavitating flow features in a convergent-divergent test section. Most importantly, a two-way transition algorithm is newly developed mainly based on the shape of resolved cavities and the relative size of microscale bubbles compared to the cells, for taking the transition between microscale discrete bubbles and macroscale vapor cavities into consideration. The transient flow field of the two-phase system is described by the filtered Navier-Stokes equation and the sub-grid scale model. The volume of fluid (VOF) method and a discrete bubble model (DBM) are combined for simulating resolvable water -vapor interfaces and unresolvable discrete bubbles, respectively. Applying the proposed multiscale modeling framework, the dissipated bubbles caused by the collapse of shedding cavities that are unable to be represented by the VOF method are well predicted. The results show that the VOF-DBM model is less sensitive to the mesh resolution compared to the VOF method and it is found the dissipated bubbles are transporting around the vortex core region. Detailed bubble dynamics including DBM to VOF and VOF to DBM transitions and the interaction between macroscale cavities and microscale bubbles are well presented, indicating that the proposed VOF-DBM model is a promising approach to reveal the multiscale cavitation characteristics within limited computing resources.

嘉利特荏原泵业有限公司(简称嘉利特荏原)秉持"求精、求专、求特"的经营理念及"精益、包容、创新、热诚"的核心价值观,探索标签、标杆、标准"三标"发展之路:通过与世界泵业龙头企业合资,贴上国际知名品牌标签;打造特种离心泵领域一流企业,树立行业标杆;参与标准制修订,增强行业话语权.

A hydrogenation feed multistage pump with a double-suction impeller at the first stage is one of the key equipment in a refinery hydrocracking unit. Due to high power consumption and low energy efficiency, conducting structural optimization design and reducing energy losses for this pump is necessary. In this study, an optimization method based on the particle swarm optimization (PSO) algorithm and least squares support vector regression (LSSVR) surrogate model is proposed. Firstly, the parameters concerning the double-suction impeller and single-suction impeller are selected as optimize variables. Head and efficiency are selected as the optimization objectives. And the head and efficiency are increased by 3.99% and 2.91% respectively through optimization. Then, energy loss analysis of the pump is conducted by introducing the entropy production method. The result shows that the pump optimized by PSO-LSSVR surrogate model can reduce 9% energy consumption under nominal flow. Finally, flow analysis reveals that the optimized scheme can suppress the horseshoe vortex at the leading edge of the impeller and the wake vortex at the trailing edge, which is the main contribution to the energy efficiency improvement. This study provides a new insight for optimizing multistage centrifugal pumps to achieve high efficiency and low energy consumption.

简述了传统轴承油润滑方式的缺点,介绍了悬臂泵轴承箱完全油雾润滑方式的工作原理、优点及轴承结构设计。

现代磷复肥工业用浆料泵要求过流部件耐腐耐磨、密封可靠与高效节能,但现有产品能耗高,寿命短,密封效果差,运行时不能调节转子间隙。介绍的新型高效耐腐耐磨浆料泵设计更加符合介质流动特性,泵效率高,泵体更加耐磨,叶轮不易堵塞,填料密封泄漏小,使用寿命长,可以不停机调整转子间隙,方便装拆。

本文阐述了离心泵转子进行动、静平衡的目的、方法、使用设备、平衡精度等级以及残余不平衡量的计算方法。