Numerical Prediction Of Cavitation In Pumps

Numerical Prediction Of Cavitation In Pumps

 

ABSTRACT
With the increase in power per unit of volume for modem pumps, driven by manufacturing costs reduction, cavitation becomes more arid more the main limiting factor in pump design. The classical one-dimensional design rules applied for decades are no longer sufficient, and for this reason, there is a strong need for more accurate numerical tools to predict the cavitation behavior of pumps.
An original cavitation prediction method is presented and its results are compared to experimental data for five pumps of specific speeds from 15 to 125 (775 to 6500 US units). The numerical method introduced in this paper for the prediction of the cavitation development in pumps is a simplified version of a previously developed program successfully used in similar cases. Motivation for this simplification was to allow the program usage during the design process of suction impellers. The accuracy of this simplified method as well as its usage as a design tool is discussed. 

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Numerical Prediction Of Cavitation In Pumps
حجم: 687 کیلوبایت

Computational Fluid Dynamical Analysis Of Complex Internal Flows In Centrifugal Pumps

Computational Fluid Dynamical Analysis Of Complex Internal Flows In Centrifugal Pumps

 

ABSTRACT 

A commercial computational fluid dynamics (CFD) computer code was employed to compute the flow field from 105 percent down to 21. percent of the 4525 gpm BEP flow rate of a 1785 rpm, 1500 specific speed impeller of 13,000 suction specific speed. Suction and discharge recirculation were both computed, and the results agreed in all details that have also been observed experimentally. The insights gained from these computations led to the design and construction of a new impeller aimed a smoother minimum flow operation. The same code was then applied to the computation of the highly three-dimensional flow field of the diffusing crossover of a 325 gpm, 3580 rpm, 900 to 1000 specific speed multistage volute pump. Flow distortions produced by this crossover were computed at the outlet to the impeller of the succeeding stage, and the effects on performance were estimated. Candidate improvements to the crossover were evaluated with the same code, illustrating the utility of CFD as a design and improvement tool. This tool can be used to improve pump performance and reliability in many different areas. 

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Computational Fluid Dynamical Analysis Of Complex Internal Flows In Centrifugal Pumps
حجم: 369 کیلوبایت

ارتقاء یک سیستم تزریق بزرگ برای توربین بخار، GE Oil & Gas

 Enhancement of a large injection system for steam turbines, 

GE Oil & Gas

دریافت
حجم: 551 کیلوبایت

بهینه سازی هیدرولیکی کمپرسورهای سانتریفوژ - GE Oil & Gas

Centrifugal compressors return channel optimization by means of

 advanced 3-D computational fluid dynamics

چکیده:

در صنایع نفت و گاز، نیاز به راندمان بالا باعث رشد مداوم فن آوری در این حوزه شده است. اگرچه ارتقاء طراحی پروانه به عنوان مساله ای رایج چه از نظر تئوری و چه از نظر عملی و صنعتی مورد توجه بوده است، اما اجزاء ثابت همانند استاتور در کمپرسورها به این اندازه در کانون توجه نبوده اند. دلیل این امر آن است که محفظه و کانالهای برگشتی ثابت نسبت به پروانه تاثیر کمتری بر روی عملکرد کلی کمپرسور دارند.با این وجود .....

دریافت
عنوان: ge centrifugal_compressors
حجم: 608 کیلوبایت

Panel Discussion on Inducer Design Criteri

Panel Discussion on Inducer Design Criteria

معیار های طراحی ایندیوسر

This article reports a panel discussion titled Inducer Design Criteria presented at the 9th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery (ISROMAC-9). The presentations of the panelists and the subsequent discussions are summarized. It is shown that cavitation instabilities are major problems in modern turbopumps and that design criteria to eliminate them are needed. Available design methods for inducers and marine propellers are reviewed, and new criteria to enhance stability are proposed. The current status of CFD is reviewed and an example of successful application is shown. Discussions of several specific topics are reported and future research needs are noted.

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Panel Discussion on Inducer Design Criteria
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Optimization of Vane Diffuser in a Mixed-Flow Pump for High Efficiency Design

Optimization of Vane Diffuser in a Mixed-Flow Pump 

for High Efficiency Design

Abstract

This paper presents an optimization procedure for high-efficiency design of a mixed-flow pump. Optimization techniques based on a weighted-average surrogate model are used to optimize a vane diffuser of a mixed-flow pump.

Validation of the numerical results is performed through experimental data for head, power and efficiency. Three-level full factorial design is used to generate nine design points within the design space. Three-dimensional Reynoldsaveraged Navier-Stokes equations with the shear stress transport turbulence model are discretized by using finite volume approximation and solved on hexahedral grids to evaluate the efficiency as the objective function. In order to reduce pressure loss in the vane diffuser, two variables defining the straight vane length ratio and the diffusion area ratio are selected as design variables in the present optimization. As the results of the design optimization, the efficiency at the design flow coefficient is improved by 7.05% and the off-design efficiencies are also improved in comparison with the reference design.

Keywords: Mixed-flow pump, Impeller, Vane diffuser, Efficiency, Optimization, Weighted-average surrogate model.

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Optimization of Vane Diffuser in a Mixed-Flow Pump for High Efficiency Design

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CFD Simulation of Centrifugal Pump Impeller Using ANSYS-CFX

CFD Simulation of Centrifugal Pump Impeller Using 

ANSYS-CFX

ABSTRACT: Centrifugal pumps are a most commonly used in different fields like industries, agriculture and domestic applications. Computational Fluid Dynamics is most commonly used tool for simulation and analysis. 3-D numerical CFD tool is used for simulation of the flow field characteristics inside the turbo machinery. CFD simulation makes it possible to visualize the flow condition inside centrifugal pump. The present paper describes the head, power, efficiency and to evaluate the pump performance using the ANSYS CFX-14, a computational fluid dynamics simulation tool. These simulations of centrifugal pumps are strongly related to cavitation flow phenomena, which may occur in either the rotating runner-impeller or the stationary parts of the centrifugal pumps. The numerical simulation can be used to detect the cavitation in centrifugal pump and to get safe range of operating at different flow rate and rotating speed.

KEYWORDS: Centrifugal pump impeller, CFD, Head, Power, Efficiency, Cavitation.

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CFD Simulation of Centrifugal Pump Impeller
Size: 1.2 MB

طراحی پمپ در شرکت تدبیر انرژی امید

یکی از فعالیت های اصلی شرکت تدبیر انرژی امید انجام طراحی هیدرولیکی و مکانیکی پمپ های API 610 و پمپ مصارف خاص از ابتدا تا انتها شامل انجام طراحی هیدرولیکی، طراحی مکانیکی، تهیه نقشه های ساخت و مونتاژ و مدارک و مستندات مربوطه می باشد. تمام طراحی و تحلیل هیدرولیکی و مکانیکی توسط نرم افزارهای روز دنیا در این زمینه مانند    CFturbo, Ansys, Solidworks, Catia انجام می پذیرد.

در زیر نمونه ای از کارهای انجام شده توسط کارشناسان این شرکت آورده شده است.

تحلیل پروانه و ایندیوسر

نقشه سه بعدی پمپ OH2  طراحی شده بر اساس استاندارد API610 11^th Ed.

مدل های سه بعدی پوسته پمپ BB1 دو طبقه با پروانه یک مکشه

Inducer Design That Avoids Rotating Cavitation

این مقاله جهت استفاده طراحان پمپ و علاقه مندان در بخش مقالات به اشتراک گذاشته شده است.

به بخش مقالات رجوع کنید.

Inducer Design That Avoids Rotating Cavitation

Abstract:

Rotating cavitation instabilities in inducers are often encountered in turbopumps of rocket engines even in the normal running conditions.

They impact on bearings radial loads, on pipe pressure oscillations and then decrease the engine reliability. The inducer presented here was designed with the goal to suppress these instabilities.