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Research on Theoretical Model of Dynamic Bulk Modulus of Gas-Containing Hydraulic Oil

Xiaoming Yuan, Xuan Zhu, Chu Wang, Lijie Zhang
2019 IEEE Access  
This research can provide a reference for optimizing the theoretical model of the dynamic bulk modulus of the gas-containing hydraulic oil.  ...  Therefore, it is necessary to research the dynamic bulk modulus of the gas-containing hydraulic oil.  ...  Scholars have conducted a lot of research on the bulk modulus of gas-containing fluids.  ... 
doi:10.1109/access.2019.2959058 fatcat:6nbrw62xwzbq7b3i2rzvefdzpy

Page 527 of Journal of Aircraft Vol. 13, Issue 7 [page]

1976 Journal of Aircraft  
Laboratory tests on a typical shock strut verified the theory that oil properties such as bulk modulus and volume are affected very little by the presence of a dissolved gas.  ...  He reported that for a content of only 0.17% (by volume) of compressible en- trained air at 3000 psig, the theoretical bulk modulus is cut in half.  ... 

Mathematical model for bulk modulus of hydraulic oil containing air bubbles

Sayako SAKAMA, Yutaka TANAKA, Hiroyuki GOTO
2015 Mechanical Engineering Journal  
Moreover, to clarify the relationship between the amount of air bubbles and the effective bulk modulus of oil, we propose a mathematical model of the bulk modulus of oil containing air bubbles.  ...  We focus on the relationship between the change in the bulk modulus and elimination of air bubbles from the hydraulic fluid and experimentally measure the bulk modulus of the hydraulic oil with and without  ...  Acknowledgments This work was supported by the Fluid Power Technology Promotion Foundation, JSPS KAKENHI Grant Number 259669, 26420086, and a grant-in-aid from the Ministry of Economy, Trade and Industry  ... 
doi:10.1299/mej.15-00347 fatcat:eg5lgoct6nc5hi2ghvltrhihy4

Novel Methods for Modeling and Online Measurement of Effective Bulk Modulus of Flowing Oil

Baolong Geng, Lichen Gu, Jiamin Liu
2020 IEEE Access  
Considering the log-normal distribution of bubble size in oil, an improved static oil model (Model B) is developed to calculate the bulk modulus of the motionless oil under the dynamic pressure.  ...  The present study primarily focuses on the effect of steady pressure on the bulk modulus of static oil.  ...  THE EFFECTIVE BULK MODULUS MODEL OF FLOWING OIL (MODEL C) The oil compressed by the pump in the hydraulic pipeline maintains the one-way movement on the way to the actuator or the commutator.  ... 
doi:10.1109/access.2020.2968086 fatcat:flhqtye7frev3d43g6knqiqxfi

Oil compressibility and polytropic air compression analysis for oleopneumatic shock struts

M. K. WAHI
1976 Journal of Aircraft  
Laboratory tests on a typical shock strut verified the theory that oil properties such as bulk modulus and volume are affected very little by the presence of a dissolved gas.  ...  He reported that for a content of only 0.17% (by volume) of compressible en- trained air at 3000 psig, the theoretical bulk modulus is cut in half.  ... 
doi:10.2514/3.44540 fatcat:x5alyldrorgwjplmjur5q3rk5q

Fluid Bulk Modulus: A Literature Survey

Hossein Gholizadeh, Richard Burton, Greg Schoenau
2011 International Journal of Fluid Power  
The objective of this paper is to first define some of the more common definitions of bulk modulus and then present a summary of the literature that is based on fluid bulk modulus.  ...  The pressure and temperature range over which these bulk modulus measurements can be made is dependent on the design of the test apparatus.  ...  The presence of air/gas in hydraulic systems (which always changes with the pressure and temperature variations) and the elasticity of the container will affect the value of bulk modulus in hydraulic systems  ... 
doi:10.1080/14399776.2011.10781033 fatcat:bzc35lgtzvaxjkdw4aoafovq5m

Modeling and simulation of low pressure oil-hydraulic pipeline transients

Dan Jiang, Songjing Li, Kevin A. Edge, Wen Zeng
2012 Computers & Fluids  
2012) Modeling and simulation of low pressure oil-hydraulic pipeline transients. Computers and Fluids, 67. pp. 79-86.  ...  The accurate prediction of behavior largely depends on three generally unknown parameters required by the model, namely: the initial air bubble volume in the oil, and the air release and re-solution time  ...  Salvatore Mancó of Politecnico di Torino, Italy, for providing the hydraulic pump and electric drive used in the test rig at University of Bath, and also for introducing the authors to the use of a steel  ... 
doi:10.1016/j.compfluid.2012.07.005 fatcat:4s3zbko2xfho5k5r7xgj3nv724

Modelling and validation of a regenerative shock absorber system

Ruichen Wang, Zhi Chen, Haijun Xu, Karsten Schmidt, Fengshou Gu, Andrew.D. Ball
2014 2014 20th International Conference on Automation and Computing  
The dynamic modeling is performed for the evaluation of design concept and the feasibility studies of regenerative shock absorber system theoretically.  ...  This paper presents the dynamic modeling and a test system of a regenerative shock absorber system which converts vibration motion into rotary motion through the adjustment of hydraulic flow.  ...  In form of air bubbles in test system leads to the reduction of oil reliability and effective bulk modulus.  ... 
doi:10.1109/iconac.2014.6935456 dblp:conf/iconac/WangCXSGB14 fatcat:t4ggkcjakfayzag2na45wcibdy

Clean Sky 2 – Project PALACE: Aeration's Experimental Sound Velocity Investigations for High Speed Gerotor Simulations

MARY Benoit, FAGOT Gaetan, GRAS Thibaut, GOTH Yvon, MNASSRI Ilyes
2020 Zenodo  
The liquid used in hydraulic systems always contains some gas, which is dissolved in the liquid at high pressure and tends to be released in a free form (i.e. undissolved as bubbles) when pressure drops  ...  To model the relative density of the equivalent fluid, modified Henry's law is applied in Simcenter Amesim v.16 to predict the fraction of undissolved gas or vapor.  ...  Zhou [13] compares CFD models with dynamic measurements. With this method, fluid density and bulk modulus have been specified.  ... 
doi:10.5281/zenodo.4618118 fatcat:hg6ryy2kvvh3nnoueje7h37gsq

Thermo-Hydraulic Modelling and Experimental Validation of an Electro-Hydraulic Compact Drive

Søren Ketelsen, Sebastian Michel, Torben O. Andersen, Morten Kjeld Ebbesen, Jürgen Weber, Lasse Schmidt
2021 Energies  
Our paper presents a lumped thermo-hydraulic model derived from the conservation of mass and energy. The derived model was experimentally validated based on experimental data from an ECD prototype.  ...  In this power range, ECDs generally rely on passive cooling to keep oil and system temperatures within the tolerated range.  ...  (b) Modelled oil-air mixture bulk moduli. Dashed lines include the effect of mechanical elasticity with β mech = 2 GPa.β is the temperature independent bulk modulus.  ... 
doi:10.3390/en14092375 doaj:651506ab7c014897b56cdb1dcadd9fc5 fatcat:sxqz5ywp6vekhb2ds423h3fteu

Dynamic Disturbance and Error Analysis of Flexible Support System for Large Optical Mirror Processing

Zujin Jin, Gang Cheng, Shichang Xu, Wei Gu
2021 Applied Sciences  
It not only provides a theoretical basis for improving the support accuracy of the FSS but also provides a foundation for the application of the FSS in the processing stage of large optical mirrors.  ...  By measuring the support height, support pressure, and support rigidity error, the effectiveness of the established mathematical disturbance model of FSS is further verified.  ...  Based on an improvement of Henry's law and the polytropic process equation for gases, Yuan et al. proposed a modified model for the dynamic bulk modulus of gas-containing hydraulic oil.  ... 
doi:10.3390/app11062715 fatcat:xmsrfwz2fvcqnlyifocmnslw7a

Modelling fracture formation and propagation in geo-materials

Michael A. Maedo, Marcelo Sánchez, Leonardo Guimarães, Osvaldo Manzoli, Pedro Cleto, A. Tarantino, E. Ibraim
2019 E3S Web of Conferences  
In this work, finite elements with high aspect ratio are used to study the hydraulic fracture process in the context of conventional continuum constitutive (stress-strain) relationships based on the damage  ...  The modelling of fracture formation and propagation in geo-materials is a subject of interest in several problems and applications.  ...  One of the first theoretical/analytical approaches dealing with the formation of fractures correspond to the so-called PKN [2] and KGD models [3] .  ... 
doi:10.1051/e3sconf/20199216003 fatcat:gdmlxmstq5fp7oacvkwfwxlqky

Numerical Simulations of Fracture Propagation in Jointed Shale Reservoirs under CO2 Fracturing

Qi Zhang, Dan Ma, Jiangfeng Liu, Jiehao Wang, Xibing Li, Zilong Zhou
2019 Geofluids  
Based on the above, a damage-based coupled model of rock deformation and gas flow is used to simulate the fracturing process in jointed shale wells with CO2 fracturing.  ...  We validate our model by comparing the simulation results with theoretical solutions.  ...  Acknowledgments This work was supported by the National Natural Science Foundation of China (51804339), the China Postdoctoral Science Foundation (2018M640760), and the Innovation-Driven Project of Central  ... 
doi:10.1155/2019/2624716 fatcat:ns44je7ntfg2niz4k5v7wjivpq

Modeling of Hydrogas Unit for Tracked Vehicle Suspension

H. Hammad, A. Salem, I. Mostafa, I. Elsherif
2015 International Conference on Aerospace Sciences and Aviation Technology  
The theoretical study includes modeling of the hydro gas suspension unit mathematically and validation of the developed model using MATLAB/SIMULINK.  ...  The obtained results show that the proposed hydro gas suspension system is more acceptable than the conventional one.  ...  The following assumptions were considered for developing the mathematical model [8] [9] [10] : 1-The density and bulk , s modulus of oil are constant. 2-Coefficient of discharge (C d ) is assumed constant  ... 
doi:10.21608/asat.2015.22887 fatcat:2qx6omgzrbgkjdi3kemp3ygjce

The study of unsteady operation mode of the crude oil trunk pipeline in case of a sudden stop flow

Zbigniew Fąfara, Rafał Matuła, Roman Mazur
2017 AGH Drilling Oil Gas  
-the diameter of the pipe, e -the wall thickness, E -the modulus of elasticity for the wall, K -the bulk modulus of the contained fluid.  ...  forecasting dynamics changes of hydraulic jump along pipeline route caused by stops pumping units.  ... 
doi:10.7494/drill.2017.34.2.349 fatcat:jpjw2nratfbg7gktodpkv7ngbm
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