Simulation of Unsteady Flow Characteristics of the Reciprocating Pump Check Valve for High Pressure and High Flow Water Medium

2021 ◽  
Vol 144 (3) ◽  
Author(s):  
Jie Dong ◽  
Yinshui Liu ◽  
Hong Ji ◽  
Liejiang Wei ◽  
Defa Wu
Keyword(s):  
High Pressure ◽  
Fluid Dynamic ◽  
Check Valve ◽  
Initial Pressure ◽  
Lower Surface ◽  
Flow Coefficient ◽  
Valve Lift ◽  
Water Medium ◽  
Flow State ◽  
Reciprocating Pump

Abstract The distribution efficiency of the check valve directly affects the performance of the reciprocating pump. The flow coefficient is an important evaluation criterion for the flow capacity of the valve port, and it is of great significance to the design of the valve structure and even the control of cavitation. The traditional design uses flow coefficient as a fixed value, however, the flow state and flow coefficient will change during valve movement. In this study, a three-dimensional transient computational fluid dynamic model for high-pressure and large-flow reciprocating pump valve is established. The dynamic grid simulation method of coupling for the valves and plunger is innovatively proposed, and experimental verification was carried out. The flow state and pressure characteristics for the suction valve under high outlet pressure are analyzed, and the change rule of the suction coefficient is found. The research results show that the initial pressure of the plunger cavity prolongs the negative pressure duration of the plunger cavity when the valve is opened and increases the risk of cavitation of the valve. During the process from valve opening to maximum lift, the suction coefficient first increases and then decreases, and finally remains between 0.5 and 0.6. When the valve lift is large, two-stage throttling occurs, and the flow state will change from cylindrical jet on the lower surface of the valve disk to annular jet, which is beneficial to improve the suction coefficient.

Study of Fuel Injection Quantity Fluctuation in High Pressure Common Rail System in Entire Operating Conditions

2012 ◽  
Vol 562-564 ◽  
pp. 1048-1053 ◽  
Author(s):  
Bing Qi Tian ◽  
Li Yun Fan ◽  
Xiu Zhen Ma ◽  
Hao Wang ◽  
Hong Bin Liu
Keyword(s):  
High Pressure ◽  
Fuel Injection ◽  
Operating Conditions ◽  
Common Rail ◽  
Flow Coefficient ◽  
Valve Lift ◽  
Orifice Diameter ◽  
Common Rail System ◽  
Injection Quantity ◽  
High Pressure Common Rail

Variations in high pressure common rail (HPCR) system characteristic parameters influence injection characteristics and lead to fluctuation of fuel injection quantity (FIQ). The fuel injection quantity fluctuation (FIQF) has adverse affects both on coherence and stability of HPCR system. Numerical simulation model of HPCR has been developed and its accuracy has been validated by experimental results. Influence law and generation mechanism of FIQF caused by variations of different parameters such as fuel return pressure, solenoid reset force, control valve lift, fuel return orifice (A orifice) diameter, fuel inlet orifice (Z orifice) diameter, injector needle lift, needle pre-tightening force and injector flow coefficient in entire operating conditions have been analyzed.

OPTIMIZATION OF FLOW COEFFICIENT FOR PAN CHECK VALVE BY FLUID DYNAMIC ANALYSIS

2010 ◽  
Author(s):  
Joon-Ho Lee ◽  
Xue-Guan Song ◽  
San-Mo Kang ◽  
Young-Chul Park ◽  
Nader Barsoum ◽  
...  
Keyword(s):  
Dynamic Analysis ◽  
Fluid Dynamic ◽  
Check Valve ◽  
Flow Coefficient

Influence of Valve Lift and Throttle Angle on Intake Flow in a High-Performance Four-Stroke Motorcycle Engine

2006 ◽  
Vol 128 (4) ◽  
pp. 934-941 ◽  
Author(s):  
Angelo Algieri ◽  
Sergio Bova ◽  
Carmine De Bartolo
Keyword(s):  
Flow Structure ◽  
High Performance ◽  
Laser Doppler Anemometry ◽  
Fluid Dynamic ◽  
Great Influence ◽  
Flow Coefficient ◽  
Valve Lift ◽  
Cylinder Axis ◽  
Intake Flow ◽  
Motorcycle Engine

A high-performance four-stroke motorcycle engine was analyzed at a steady flow rig. The aim of the work was to characterize the fluid dynamic behavior of the engine head during the intake phase. To this purpose a twofold approach was adopted: the dimensionless flow coefficient was used to evaluate the global breathability of the intake system, while the laser doppler anemometry (LDA) technique was employed to define the flow structure within the combustion chamber. The analysis gave evidence of two contrarotating vortices with axes parallel to the cylinder axis and showed variations in the flow structure when moving away from the engine head. Furthermore, the study highlighted the great influence of the throttle angle on the head fluid dynamic efficiency and how this influence changes with the valve lift. Experimental data were correlated by a single curve adopting a new dimensionless plot. Moreover, LDA measurements were used to evaluate the angular momentum of the flux and an equivalent swirl coefficient, and to correlate them to a previous global swirl characterization carried out on the same engine head using an impulse swirl meter.

scholarly journals Computational Fluid Dynamic Simulation of Single Bubble Growth under High-Pressure Pool Boiling Conditions

2016 ◽  
Vol 48 (4) ◽  
pp. 859-869 ◽  
Author(s):  
Janani Murallidharan ◽  
Giovanni Giustini ◽  
Yohei Sato ◽  
Bojan Ničeno ◽  
Vittorio Badalassi ◽  
...  
Keyword(s):  
High Pressure ◽  
Dynamic Simulation ◽  
Computational Fluid Dynamic ◽  
Bubble Growth ◽  
Fluid Dynamic ◽  
Pool Boiling ◽  
Computational Fluid Dynamic Simulation ◽  
Single Bubble

Transient flow behaviors of the check valve with different spool-head angle in high-pressure hydrogen storage systems

2022 ◽  
Vol 46 ◽  
pp. 103761
Author(s):  
Jianjun Ye ◽  
Zhenhua Zhao ◽  
Junxu Cui ◽  
Zhengli Hua ◽  
Wenzhu Peng ◽  
...  
Keyword(s):  
High Pressure ◽  
Hydrogen Storage ◽  
Transient Flow ◽  
Storage Systems ◽  
Check Valve ◽  
Pressure Hydrogen

Thermo-Fluid-Dynamic Design of Reciprocating Compressor Cylinders by Fluid Structure Interaction (FSI)

2011 ◽  
Author(s):  
Riccardo Traversari ◽  
Alessandro Rossi ◽  
Marco Faretra
Keyword(s):  
High Speed ◽  
Fluid Dynamic ◽  
Fluid Structure Interaction ◽  
Classical Equation ◽  
Flow Coefficient ◽  
Reciprocating Compressor ◽  
Complex Situation ◽  
Fluid Structure ◽  
Associated Gas ◽  
Structure Interaction

Pressure losses at the cylinder valves of reciprocating compressors are generally calculated by the classical equation of the flow through an orifice, with flow coefficient determined in steady conditions. Rotational speed has increased in the last decade to reduce compressor physical dimensions, weight and cost. Cylinder valves and associated gas passages became then more and more critical, as they determine specific consumption and throughput. An advanced approach, based on the new Fluid Structure Interaction (FSI) software, which allows to deal simultaneously with thermodynamic, motion and deformation phenomena, was utilized to simulate the complex situation that occurs in a reciprocating compressor cylinder during the motion of the piston. In particular, the pressure loss through valves, ducts and manifolds was investigated. A 3D CFD Model, simulating a cylinder with suction and discharge valves, was developed and experimentally validated. The analysis was performed in transient and turbulent condition, with compressible fluid, utilizing a deformable mesh. The 3D domain simulating the compression chamber was considered variable with the law of motion of the piston and the valve rings mobile according to the fluid dynamic forces acting on them. This procedure is particularly useful for an accurate valve loss evaluation in case of high speed compressors and heavy gases. Also very high pressure cylinders, including LDPE applications, where the ducts are very small and MW close to the water one, can benefit from the new method.

The Effect of Technological Parameter on the Co-liquefaction of Coal with Lignin

2012 ◽  
Vol 577 ◽  
pp. 167-170
Author(s):  
Qing Jie Tang ◽  
Zhi Hong Wang
Keyword(s):  
High Pressure ◽  
Production Rate ◽  
Reaction Temperature ◽  
Conversion Rate ◽  
Technological Parameter ◽  
Initial Pressure ◽  
Oil Production ◽  
Important Influence ◽  
Mixture Ratio

The co-liquefaction of coal with lignin was studied by minisize high pressure reactor, tetralin and Fe2O3 were used as solvent and catalyst, and the study was focused on the reaction temperature, initial pressure of hydrogen and mixture ratio of lignin with coal. The results showed that the reaction temperature, the initial pressure and mixture ratio has the important influence on the conversion rate of coal, the oil production rate in the process of co-liquefaction with coal and the lignin. Effect of co-liquefaction is best in reaction temperature 440°C, initial pressure 9Mpa, mixture ratio of lignin and coal for 2∶8, the conversion rate of coal and the oil production rate respectively achieves 87.66% and 50.39%.

Design and Analysis of a High Pressure Turbine Using Computational Methods for Small Gas Turbine Application

2013 ◽  
Author(s):  
Kishor Kumar ◽  
R. Prathapanayaka ◽  
S. V. Ramana Murthy ◽  
S. Kishore Kumar ◽  
T. M. Ajay Krishna
Keyword(s):  
High Pressure ◽  
Gas Turbine ◽  
Computational Methods ◽  
Gas Turbine Engine ◽  
Flow Coefficient ◽  
Design Parameters ◽  
Convergence Criterion ◽  
Turbine Engine ◽  
Design Point ◽  
Ansys Cfx

This paper describes the aerodynamic design and analysis of a high-pressure, single-stage axial flow turbine suitable for small gas turbine engine application using computational methods. The specifications of turbine were based on the need of a typical high-pressure compressor and geometric restrictions of small gas turbine engine. Baseline design parameters such as flow coefficient, stage loading coefficient are close to 0.23 and 1.22 respectively with maximum flow expansion in the NGV rows. In the preliminary design mode, the meanline approach is used to generate the turbine flow path and the design point performance is achieved by considering three blade sections at hub, mean and tip using the AMDC+KO+MK+BSM loss models to meet the design constraints. An average exit swirl angle of less than 5 degrees is achieved leading to minimum losses in the stage. Also, NGV and rotor blade numbers were chosen based on the optimum blade solidity. Blade profile is redesigned using the results from blade-to-blade analysis and through-flow analysis based on an enhanced Dawes BTOB3D flow solver. Using PbCFD (Pushbutton CFD) and commercially available CFD software ANSYS-CFX, aero-thermodynamic parameters like pressure ratios, aerodynamic power, and efficiencies are computed and these results are compared with one another. The boundary conditions, convergence criterion, and turbulence model used in CFD computations are set uniform for comparison with 8 per cent turbulence intensity. Grid independence study is performed at design point to optimize the grid density for off-design performance predictions. ANSYS-CFX and PbCFD have predicted higher efficiency of 3.4% and 1.2% respectively with respect to targeted efficiency of 89 per cent.

Wave flows induced by lifting of a rectangular beam partly immersed in shallow water

2017 ◽  
Vol 816 ◽  
pp. 442-467 ◽  
Author(s):  
Vladimir V. Ostapenko ◽  
Olyana A. Kovyrkina
Keyword(s):  
Shallow Water ◽  
Liquid Flow ◽  
Beam Width ◽  
Lower Surface ◽  
Water Medium ◽  
Second Stage ◽  
Rectangular Beam ◽  
Third Stage ◽  
Channel Bottom ◽  
Long Wave Approximation

Flows induced by vertical lifting of a rectangular beam partly immersed into shallow water in a rectangular prismatic channel with a horizontal bottom are studied within the framework of the long-wave approximation. The beam width coincides with the channel width and the lower and upper planes of the beam are parallel to the channel bottom. The lifting process in the general case consists of three stages. At the first stage, the lower surface of the beam is completely located in the liquid, which ascends following the beam under the action of hydrostatic pressure. At the second stage, the edges of the lower surface of the beam leave the water medium, the wetted part of the beam becomes smaller, and the liquid under this part of the beam move upward. At the beginning of the third stage, the beam is separated from water; as a result, liquid lifting that occurred at the second stage leads to the formation of two diverging waves. The liquid flow in the domain adjacent to the lower surface of the beam is calculated analytically, while the liquid flow outside this domain is obtained by means of numerical calculations by the CABARET (compact accurately boundary-adjusting high-resolution technique) scheme, which provides the second order of accuracy on smooth solutions.

Increasing Inducer Stability and Suction Performance With a Stability Control Device

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
R. Lundgreen ◽  
D. Maynes ◽  
S. Gorrell ◽  
K. Oliphant
Keyword(s):  
Fluid Dynamic ◽  
Leading Edge ◽  
High Energy ◽  
Stability Control ◽  
Control Device ◽  
Design Flow ◽  
Flow Coefficient ◽  
Blade Tip ◽  
Rotordynamic Forces ◽  
Suction Performance

An inducer is used as the first stage of high suction performance pump. It pressurizes the fluid to delay the onset of cavitation, which can adversely affect performance in a centrifugal pump. In this paper, the performance of a water pump inducer has been explored with and without the implementation of a stability control device (SCD). This device is an inlet cover bleed system that removes high-energy fluid near the blade leading edge and reinjects it back upstream. The research was conducted by running multiphase, time-accurate computational fluid dynamic (CFD) simulations at the design flow coefficient and at low, off-design flow coefficients. The suction performance and stability for the same inducer with and without the implementation of the SCD has been explored. An improvement in stability and suction performance was observed when the SCD was implemented. Without the SCD, the inducer developed backflow at the blade tip, which led to rotating cavitation and larger rotordynamic forces. With the SCD, no significant cavitation instabilities developed, and the rotordynamic forces remained small. The lack of cavitation instabilities also allowed the inducer to operate at lower inlet pressures, increasing the suction performance of the inducer.

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