Investigation of Fluid Transients in Centrifugal Pump Integrated System With MultiChannel Pressure Vessel

2013 ◽  
Vol 135 (6) ◽  
Author(s):  
Wuyi Wan ◽  
Wenrui Huang
Keyword(s):  
Centrifugal Pump ◽  
Pressure Vessel ◽  
Design Method ◽  
Oscillation Amplitude ◽  
Pressure Vessels ◽  
Integrated System ◽  
Centrifugal Pumps ◽  
Transient Pressure ◽  
Improve Design ◽  
Fluid Transients

A pressure vessel is installed to prevent transient vacuum and overpressure in centrifugal pump integrated system. In order to study the transient response of the pressure vessel with multichannels and improve design approach, an integrated system with two centrifugal pumps and a pressure vessel is presented. Based on the water hammer method of characteristics (MOC), the integrated numerical model and program are established by combining pumps, valves and pressure vessels in the integrated systems. Transient pressure process and gas volume variation are simulated for the pressure vessel. The Oscillation amplitude and frequency are obtained, and then the extreme hydraulic transient pressures are analyzed and compared. An optimal design method is provided to determine the safe and economic mass (SEM) of gas (nitrogen) and corresponding optimal safe and economic volume (SEV) of pressure vessel.

Design Optimization of Splitter Blade Impeller in a Centrifugal Pump

2020 ◽  
Author(s):  
Shunya Takao ◽  
Kentarou Hayashi ◽  
Masahiro Miyabe
Keyword(s):  
Centrifugal Pump ◽  
Flow Rate ◽  
Design Method ◽  
General Purpose ◽  
Stable Operation ◽  
Centrifugal Pumps ◽  
Unstable Flow ◽  
Rate Range ◽  
Flow Rate Range ◽  
Suction Performance

Abstract In order to improve suction performance, centrifugal pumps with an inducer are used for rocket pumps, liquid gas transport such as LNG, and general-purpose pumps. Since a higher suction performance than conventional pump is required, a splitter blade that consists of a long blade and a short blade is sometimes adopted. However, the design becomes more difficult due to the increased number of parameters. The stable operation over a wide flow rate range are required in the general-purpose pumps. Therefore it is necessary to design them so that unstable flow phenomena such as surges do not occur. However, the design method to avoid them is not well understood yet. In this study, we focused on the splitter blade impeller in a general-purpose low-speed centrifugal pump with an inducer. Six parameters such as leading edge position and trailing edge position of the short blade for both hub-side and tip-side were set as design ones. A multi-objective optimization method using a commercial software was applied to improve suction performance while maintaining high efficiency. Then obtained optimal shape were analyzed by CFD calculation and extracted the feature. Furthermore, optimized impellers were manufactured and confirmed the performance over a wide flow rate range by experiments. In addition, a optimizing design method that improves pump performance at lower cost was studied.

scholarly journals Computation of Viscous Flow Inside a Double-Channel Centrifugal Pump

2014 ◽  
Vol 8 (1) ◽  
pp. 613-618
Author(s):  
Su-Lu Zheng ◽  
Xiang-Ping Wang ◽  
Rui-Hang Zheng ◽  
Ai-Ping Xia ◽  
Yi-Nian Wang ◽  
...  
Keyword(s):  
Viscous Flow ◽  
Centrifugal Pump ◽  
Design Method ◽  
Pure Water ◽  
Flow Characteristics ◽  
Internal Flow ◽  
Solid Particles ◽  
Water Medium ◽  
Centrifugal Pumps ◽  
Double Channel

The double-channel centrifugal pumps are widely used to transport the two-phase flow including big solid particles in industry and agriculture. However, the related design theory and the design method are immature by far. In practice, the revised design method based on the pure water medium is still the main method for the solid-liquid twophase double-channel pump. Therefore, it is very necessary to deeply study the flow characteristics on the condition of the pure water medium. In this paper, in order to study the flow characteristics inside a prototype double-channel centrifugal pump in the case that the delivered medium is the pure water, the SIMPLE algorithm, RNG κ-ε turbulence model, and frozen rotor method are employed to calculate the incompressible, viscous, three-dimensional internal flow. The calculation results display the variation characteristics of the internal flow field and the external performance. The results show that the predicted pump head drops with the increasing flow rate, which manifest that the pump model is of good operation stability at the whole range of working. At the design point, a strong and large vortex remain appears at the middle section of the double-channel impeller. The computational fluids dynamic technology is competent to assess the internal viscous flow inside a double-channel centrifugal pump.

Prestressing a Two-Layer Pressure Vessel by Plastic Deformation

1965 ◽  
Vol 87 (1) ◽  
pp. 97-103
Author(s):  
R. W. Schneider
Keyword(s):  
Plastic Deformation ◽  
Internal Pressure ◽  
Pressure Vessel ◽  
Work Hardening ◽  
Design Method ◽  
Strain Curve ◽  
Pressure Vessels ◽  
Stress Strain Curve ◽  
Initial Clearance ◽  
Actual Stress

A method of prestressing two-layer pressure vessels by controlled yielding of the inner layer by internal pressure is described. The required prestressing pressure depends upon the dimensions of the vessel, the initial clearance between layers, and the properties of the material of construction. The design method takes into account the actual stress-strain curve of the material and satisfies the rules of plastic flow with work-hardening. Two-layer, cylindrical vessels are discussed in detail.

scholarly journals Developing “Design by Analysis” Methodology for Windows for Pressure Vessels for Human Occupancy

2020 ◽  
Vol 6 (3) ◽  
Author(s):  
Bart Kemper ◽  
Linda Cross
Keyword(s):  
Pressure Vessel ◽  
Large Scale ◽  
Design Method ◽  
Empirical Method ◽  
Pressure Vessels ◽  
Case Review ◽  
Element Analysis ◽  
Engineering Theory ◽  
Operational Variables ◽  
Stochastic Finite Element Analysis

Abstract The ASME pressure vessels for human occupancy (PVHO) codes and standards are engineering standards developed to provide a reliable design method for pressure vessel windows. This empirical method is based primarily on years of government-sponsored testing and development and does not directly use engineering theory. This empirical algorithm makes it challenging to revise without additional large-scale physical testing. The industries using the PVHO code need a way to incorporate advances in material science, manufacturing technology, and overall engineering advances without spending years in code case review. Verification and validation techniques, coupled with stochastic finite element analysis (FEA) to address operational variables, can be the basis for a “design by analysis” method to complement the existing testing requirements to produce a full engineering package consistent with other pressure vessel and pressure vessel component design. A design method sufficiently reliable for PVHO could be used in other applications.

Failure Modes for Acrylic Polymers in Section VIII Pressure Vessels

2021 ◽  
Author(s):  
Bart Kemper ◽  
Guy Richards ◽  
Taylor Nappi ◽  
Veda Thipparthi ◽  
Ana Escobar
Keyword(s):  
Pressure Vessel ◽  
Failure Modes ◽  
Design Method ◽  
Current Method ◽  
Empirical Method ◽  
Pressure Vessels ◽  
Glassy Polymers ◽  
Acrylic Polymers ◽  
Section Viii ◽  
Vessel Material

Abstract Section VIII of the Boiler and Pressure Vessel Code is introducing the use of acrylics as a pressure vessel material. The design method is specified in ASME PVHO-1, Safety Standard for Pressure Vessels for Human Occupancy. The current method relies upon an empirical method developed in the 1960–70’s. It does not use “allowable stress” or other mechanical properties traditionally used to calculate design dimensions, but instead uses a fixed range of dimensions for specific shapes and determines the wall thickness using a curve. Understanding the PVHO-1 design assumptions and typical failure modes is important for a non-PVHO pressure vessel designer using acrylics. An ASME Codes & Standards task group is developing a “design by analysis” method (DBA) for acrylics and other glassy polymers for pressure vessel components. The proposed DBA methodology uses Verification and Validation (V&V) techniques and Finite Element Method (FEM) as the design method framework in order to advance the use of glassy polymers as pressure vessel materials.

scholarly journals The Influence of Blade Angle on the Performance of Plastic Centrifugal Pump

2020 ◽  
Vol 2020 ◽  
pp. 1-20 ◽  
Author(s):  
Jun Li ◽  
Lingfeng Tang ◽  
Yaoyao Zhang
Keyword(s):  
Flow Field ◽  
Centrifugal Pump ◽  
Design Method ◽  
Structural Characteristics ◽  
Centrifugal Pumps ◽  
Dimensional Model ◽  
Working Pressure ◽  
Outlet Angle ◽  
Modulus Method ◽  
Inlet Angle

In order to obtain the influence of blade placement angle on the performance of plastic centrifugal pumps, this article used the velocity modulus method. Based on the method, the hydraulic design of the flow passage components of the plastic centrifugal pump was carried out, and the two-dimensional model and three-dimensional model diagram of the flow components were established. The flow field of the impeller model under different working conditions was simulated and the results were analyzed by ANSYS CFX. The influence of different fluid loads on the solid structure under design conditions on the structure characteristics of the impeller was studied by ANSYS Workbench. Impeller models with different outlet angles were established to study the influence of the outlet angle on the performance of pump, and fluid-structure interaction for different impeller models was utilized to study the influence of the outlet angle on the structural characteristics of the impeller. According to the Stepanoff velocity modulus method, considered the import prerotation, the wrap angle design method and the blade inlet angle design method were proposed. In order to study the influence of different inlet angles on the performance of pump, the inlet angle was changed to establish multiple sets of impeller models, 3D printing technology was used to print out each impeller, and performance experiments were performed on the pump equipped with the impeller. The result of the experiments showed that working pressure of plastic centrifugal pump exceeding 5 atm would cause impeller structure damage. When the outlet angle was 35°, the plastic centrifugal pump reached the highest efficiency of 81.0161% and the highest H of 35.8029. The maximum deformation caused by the flow field load on the impeller increased with the increase of the outlet angle. With the increase of the inlet angle, the efficiency and H of the plastic centrifugal pump were reduced. Under normal pressure load, the deformation of the impeller first decreased and then increased, and when β1 was 13°, the total deformation of the impeller was the smallest.

Pressure Vessel Optimization Design Based on the Finite Element Analysis

2011 ◽  
Vol 65 ◽  
pp. 281-284 ◽  
Author(s):  
Cai Li Zhang ◽  
Fan Yang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Pressure Vessel ◽  
Optimization Design ◽  
Design Method ◽  
Pressure Vessels ◽  
Design Parameters ◽  
Element Analysis ◽  
Quantitative Calculation ◽  
The Finite Element Analysis

According to pressure vessel material waste problem in the traditional design, the finite element technique is used to pressure vessel optimization design in this paper. Firstly, the finite element analysis is applied to carry out stress calculation, and we extracted the related results parameters for following calculation. Then we conducted the quantitative calculation after choosing optimization design method, and got the best design parameters which meet performance indexes. At last, we conducted the optimization design of pressure vessels using this technology. Practical results prove the validity and the practicability of this method in the pressure vessels design.

scholarly journals A Guiding Design System for Pressure Vessels based on 3D CAD

2016 ◽  
Vol 12 (05) ◽  
pp. 4
Author(s):  
Zhang Shanhui ◽  
Yang Chaoying ◽  
Xu Ning
Keyword(s):  
Pressure Vessel ◽  
3D Models ◽  
Pressure Vessels ◽  
Design System ◽  
Improve Design ◽  
3D Cad ◽  
Cad System ◽  
Design Specifications ◽  
Standard Parts Library ◽  
Parts Library

The design of pressure vessel is an extremely professional job which has heavy workload, repeated work, and rich accumulated knowledge, and it has good characteristics of serialization, generalization, standardization. Generic 3D CAD systems are not suitable for pressure vessel design. On the contrary, customized development based on 3D CAD system is needed. In this paper, a new pressure vessel design system based on Chinese 3D CAD system named SINOVATION was developed to improve design efficiency and accuracy. First, the functions and construction of pressure vessel design system were presented with the analysis of the traditional design process of pressure vessels. Second, related design specifications were managed and used flexibly in pressure vessel design system, and general parts library and standard parts library were established to improve parts reuse and accumulation. Finally, a guiding design mode was accepted for typical vessels and components to design same product series while direct modeling function was used for atypical pressure vessels. The results show that this method is helpful for embedded use of design specifications, standards and knowledge, and also provides an extensive interface for product updates and diversification. Statistical data reports and accurate engineering drawings are generated automatically based on 3D models. The quality, efficiency, and consistence are greatly improved. With the implementation and application, the system has been highly commended by customers in Chinese pressure vessel industry, especially in petrochemical industry.

Effects of Flow Coefficient on Miniature Centrifugal Pump Performance

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Guiqin Liu ◽  
Weng Kong Chan
Keyword(s):  
Centrifugal Pump ◽  
Critical Parameter ◽  
Design Method ◽  
Flow Coefficient ◽  
Design Technique ◽  
Centrifugal Pumps ◽  
Performance Study ◽  
Pump Performance ◽  
And Performance ◽  
Theoretical Results

In order to help the design of miniature centrifugal pumps, the design method for macrosize centrifugal pumps is reviewed and the critical parameter, the flow coefficient, is examined in this paper for the miniature centrifugal pumps. The performance of the pumps designed is analyzed theoretically, numerically, and experimentally. Both numerical and theoretical results show that the value of the optimized flow coefficient is approximately 1.47. This value is about five times larger than the recommended value using conventional design technique for macrosize pumps. The optimum radius ratio obtained numerically is approximately 0.4. It can be concluded that the design approach for macrosize pumps is not applicable for pumps in the scale of decimeters. The results obtained in the present study provide us guidelines on the design and performance study of the miniature centrifugal pump.

Effect of Blade Trailing Edge Cutting Angle on Unstable Flow and Vibration in a Centrifugal Pump

2020 ◽  
Vol 142 (10) ◽  
Author(s):  
Baoling Cui ◽  
Wenqing Li ◽  
Chenliang Zhang
Keyword(s):  
Centrifugal Pump ◽  
Pressure Pulsation ◽  
Low Frequency ◽  
Dominant Frequency ◽  
Design Flow ◽  
Centrifugal Pumps ◽  
Transient Pressure ◽  
Unstable Flow ◽  
Trailing Edge ◽  
Vibration Displacement

Abstract The vibration induced by the unsteady fluid exciting force in a centrifugal pump is one of the important factors affecting the reliable operation of the pump. In this study, the cutting of the blade trailing edge of a straight blade is presented to improve the unstable flow and vibration in a centrifugal pump. Based on the large eddy simulation (LES) and fluid–solid coupling method, the transient pressure pulsation, unstable flow structure, and vibration displacement of a centrifugal pump were investigated with different cutting angles of the trailing edge under the design flow rate. The external characteristics of the centrifugal pumps were calculated and compared using the shear stress transport (SST) k–ω turbulence model. The results show that the heads and efficiencies of the pumps with 30 deg and 45 deg cutting angles of the trailing edge slightly improved. The pressure pulsation on the volute evaluated by dominant frequency–amplitude and pressure pulsation energy was reduced due to the lesser average vorticity intensity and trailing vortex area in the centrifugal pump. Therefore, the vibration displacement and the vibration energy at the low frequency of the impeller decreased.

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