BATH/ASME 2018 Symposium on Fluid Power and Motion Control最新文献

{"title":"Closed Loop Position and Pre-Stress Control for a Morphing Aircraft Wing With Distributed Multi-Axis Pneumatic Actuation","authors":"Hongzhao Zhou, A. Plummer, D. Cleaver","doi":"10.1115/FPMC2018-8863","DOIUrl":"https://doi.org/10.1115/FPMC2018-8863","url":null,"abstract":"This paper presents the design and control of a morphing wing structure using an active tensegrity structure. A tensegrity structure, which is a set of compressive members (struts) stabilized by a set of tensile members (cables) is a good basis for creating a lightweight active structure, due to its potentially high stiffness-to-weight ratio, and the ease with which actuators can be embedded by replacing selected members in the structure. In this work, a multi-axis control scheme is developed for closed loop control of the shape and internal force (pre-stress) of the structure. An experimental prototype has been built, with 6 unidirectional pneumatic cylinders controlled by pulse-width-modulated switching valves. Shape change in terms of twisting and span-wise bending are demonstrated, and an optical motion tracking system is used to help investigate the dynamic position control of the structure. The structure can achieve ±15° twist change for wing angle of attack or ±10° span-wise bending in a 300mm span length. By simultaneously controlling the structural pre-stress, the geometric stiffness of the structure can also be varied. Future research is discussed, which will involve embedding the active structure in a wing aerofoil and testing in a wind tunnel.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134250988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis and Control of a Self-Contained Hydraulic Winch Drive","authors":"Lasse Schmidt, H. Pedersen, V. Donkov, T. Andersen","doi":"10.1115/FPMC2018-8889","DOIUrl":"https://doi.org/10.1115/FPMC2018-8889","url":null,"abstract":"This paper is considering the analysis and control of a self-contained hydraulic winch drive. Winch drives are used in various industries, and especially in offshore and marine applications such as fishing vessels, active heave compensation applications, cranes, oil- and gas drilling rigs, vessels for wind turbine installation and so forth. When high loads are present, such winches are typically actuated by use of hydraulics, and a main disadvantage of hydraulic actuation compared to electrical actuation is the potentially large installation space required due to the hydraulic power unit. In this paper the analysis of- and control design for a self-contained hydraulic winch drive are considered. The drive includes a single supply pump, fixed displacement motor, flow control valve, a boot-strap reservoir and integrated boost-flow functionality. Emphasis is placed on the analysis of the highly coupled dynamics, an approach to decouple the dynamics and a robust control structure able to handle various types of loads aided by model reference generation. The motion performance and robustness properties are demonstrated through simulation results, when the system is subjected to a strongly varying external load and motion reference from an offshore wind turbine blade installation system.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114687080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Numerical Approach for the Evaluation of a Capillary Viscometer Experiment","authors":"Felix Fischer, J. Bartz, K. Schmitz, L. Brouwer, H. Schwarze","doi":"10.1115/FPMC2018-8815","DOIUrl":"https://doi.org/10.1115/FPMC2018-8815","url":null,"abstract":"The dynamic viscosity of a fluid is an important input parameter for the investigation of elastohydrodynamic contacts within tribological simulation tools. In this paper, a capillary viscometer is used to analyse the viscosity of a calibration fluid for diesel injection pumps. Capillary viscometers are often used for the determination of viscosities that show a significant dependence on shear rate, pressure and temperature such as polymer melts or blood. Therefore most of the research on corrections of measured viscosities have been made using polymer melts. A new method is presented to shorten the effort in evaluating the capillary experiment.\u0000 The viscosity itself can be calculated from experimental data. Essential parameters are the radius of the capillary, its length, the capillary flow and the pressure difference over the capillary. These quantities are used in the Hagen-Poiseuille equation to calculate the viscosity, assuming laminar and monodirectional flow.\u0000 According to said equation, the viscosity depends on the geometry and the pressure gradient. A typical capillary viscometer contains three main flow irregularities. First the contraction of the flow at the capillary inlet, second the expansion of the flow at the capillary outlet and third the inlet section length of the flow after which the velocity profile is fully developed.\u0000 These flow phenomena cause pressure losses, which have to be taken into account, as well as the altered length of the laminar flow in the capillary. Furthermore, the temperature difference over the capillary also affects the outlet flow.\u0000 Therefore, in this paper, a newly developed method is proposed, which shortens the effort in pressure and length correction. The method is valid for viscometers, which provide a single phase flow of the sampling fluid. Furthermore, the proposed correction is suited for arbitrary geometries.\u0000 A numerical approach is chosen for the analysis of the experiment. In order to facilitate the experimental procedure of a capillary viscometer, a special algorithm was developed. The numerical approach uses a static CFD simulation, which is recursively passed through. If a termination condition, regarding the pressure difference between two cycles, is fulfilled, the real viscosity can be calculated in the usual way from the Hagen-Poiseuille equation. A special advantage of the proposed experimental evaluation is the general applicability for arbitrary geometries. In this paper, the procedure is validated with a well-known reference fluid and compared to data, which was gathered from a quartz viscometer experiment with the same fluid. Therefore, experiments are conducted with the capillary viscometer and compared at various pressure and temperature levels.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"13 33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125490311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of the Dynamic Characteristics of a Hydraulic Reservoir for its Air Release Efficiency Using Multiphase CFD Model","authors":"Rahelehsadat Mostafavi, D. Tiffin, K. Schmitz","doi":"10.1115/FPMC2018-8813","DOIUrl":"https://doi.org/10.1115/FPMC2018-8813","url":null,"abstract":"Undissolved air in oil causes various problems for hydraulic systems and strongly decreases the efficiency of the system. In this respect, the hydraulic reservoir as the only component that performs the function of releasing the accumulated air from the system is relevant. In recent years, the air release efficiency in hydraulic reservoirs has been studied both experimentally and in simulation. However, in none of the according studies dynamically changing flow conditions have been considered.\u0000 In this paper, the air release behaviour of a hydraulic reservoir is investigated through simulation, considering the dynamics of the system. The developed multiphase CFD model utilizes the open-source CFD tool, OpenFOAM®, based on a Lagrangian Particle Tracking (LPT) within an Eulerian phase. The simulations have been conducted varying the key variables such as oil flow rate and air load at the inlet of the reservoir and yield the air content at the outlet.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130378764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel Fine Positioning Method for Hydraulic Drives Utilizing On/Off-Valves","authors":"M. Huova, M. Linjama, L. Siivonen, T. Deubel, H. Försterling, E. Stamm","doi":"10.1115/FPMC2018-8891","DOIUrl":"https://doi.org/10.1115/FPMC2018-8891","url":null,"abstract":"This paper studies a novel on/off-valve-based fine positioning method for hydraulic drives. The method proposed utilizes four on/off-valves in independent metering configuration to reach good positioning accuracy and low power losses. Previously, servo valves have been used in precise position control of hydraulic double acting cylinders. Another approach uses on/off-valves, which are typically driven by using pulse width modulation (PWM) or, if there are parallel connected valves, pulse code modulation (PCM). Typically, both cylinder sides are modulated simultaneously. The new concept proposed uses a cylinder model to calculate a correct opening sequence for the on/off-valves, such that the target piston position is reached. The method proposed modulates single cylinder side at a time in order to achieve small piston position step sizes. Despite relying on the modelled compressibility of the fluid, the method presented requires no knowledge about the bulk modulus of the fluid. It is enough that the bulk modulus of the fluid in both cylinder chambers can be assumed equal. The paper includes the design of the control method, a simulation study proving the validity of the method, and an experimental part investigating the performance in practice. The experimental results show a positioning accuracy of +/− 1 μm with an on/off-valve-based hydraulic drive, the maximum velocity of which is 0.7 m/s.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130536424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling of the Lateral Lubricating Interfaces in External Gear Machines Considering the Effects of Cavitation","authors":"D. Thiagarajan, A. Vacca","doi":"10.1115/FPMC2018-8902","DOIUrl":"https://doi.org/10.1115/FPMC2018-8902","url":null,"abstract":"This work presents an approach for evaluating the cavitating conditions encountered in the lateral lubricating interfaces which exist between floating lateral bushings and gears in external gear machines (EGMs). Previous work in the authors’ research team had resulted in the development of a full fluid-structure-interaction (FSI)-EHD lubricating model for the lateral lubricating gaps, which was also validated against experiments. However, such a model uses a very simplified and approximate approach to consider aeration or cavitating conditions in the lubricating gap, where the pressures are simply saturated to a constant minimum value during their solution whenever they cross a minimum threshold. This subsequently results in numerically unstable predictions of pressure when substantial cavitating regions are encountered while also violating mass conservation laws.\u0000 To overcome these issues, this paper presents a stable mass conserving cavitation algorithm by implementing the universal Reynolds equation in the existing FSI-EHD model which is applicable for both full film and cavitating conditions and has been found to be applicable in several other tribological interfaces. Such a method offers to predict the onset and shape of the cavitating regions without the need for considering complex bubble dynamics. After outlining the formulation and implementation of the new cavitation algorithm, this paper also presents simulations of a commercially available EGM, where using this cavitation algorithm was found to predict realistic pressure distributions in the lubricating interface while also maintaining the stability of such a complex lubricating gap model for EGMs.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120818304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transmission of Fluid Borne Noise in the Reservoir","authors":"W. Fiebig, J. Wróbel, P. Cependa","doi":"10.1115/FPMC2018-8856","DOIUrl":"https://doi.org/10.1115/FPMC2018-8856","url":null,"abstract":"The paper presents results of research on the transmission of fluid borne noise in reservoir filled with fluid. This type of transmission of vibrational energy in the fluid occurs in fluid power units, in which hydraulic pumps are immersed in the liquid in the tank i.e. in the vertical mounting of the electric motor on the reservoir. There are vibrating elements submerged in the fluid like pumps, pipe elements, filters, etc. Due to the vibration of these elements fluid borne noise will be generated which will be transmitted to the tank structure. The transmission of fluid borne noise is dependent on natural frequencies of the tank structure. Based on model investigations, the mechanism and factors influencing the intensity of transmission of fluid borne noise in a reservoir were presented. The results of simulations with FEM were compared with the results of experimental investigations.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123055934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of Visualized Water Hydraulic Experiment System for Studying the Bubble Flow Pattern Inside Valve","authors":"Haihang Wang, Xu He, Zitong Zhao, V. Pooneeth, L. Jiao","doi":"10.1115/FPMC2018-8904","DOIUrl":"https://doi.org/10.1115/FPMC2018-8904","url":null,"abstract":"To study the flow pattern mechanism of cavitation and erosion in water hydraulic valves, a visualized water hydraulics experiment for testing the bubble flow was designed and conducted in this paper. An ergonomic design method was adopted to ensure with the characteristics of the visualized experiment platform of being modular, movable, networked, adopting a virtual three-dimensional vision and safety, respectively, were adhered. An experimental video acquisition subsystem with an optimized arrangement of 5 plane mirrors was presented to observe and analyze the bubble flow pattern in a transparent hydraulic valve. An algorithm was developed to extract the 2-D bubble features and reconstruct the 3-D bubble flow pattern. The 2-D and 3-D calculated results were analyzed, which effectively reconstructed the bubble flow. During the 2-D and 3-D results analysis for a selected period of time, the visualized water hydraulics experiment system in this paper met the expected performance requirements.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128542563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Symmetric Single Rod Cylinders With Variable Piston Area? A Comprehensive Approach to the Right Solution","authors":"G. Kolks, J. Weber","doi":"10.1115/FPMC2018-8810","DOIUrl":"https://doi.org/10.1115/FPMC2018-8810","url":null,"abstract":"In contrast to rotational hydraulic displacement units, such as pumps or motors, conventional hydraulic cylinder actuators do not allow a continuous variation of their displacement quantity: the piston area is regarded constant. In order to adapt to varying load and velocity requirements in a load cycle under torque restrictions of the driving motor, cylinder drives often implement pumps with variable displacement.\u0000 In this paper, cylinders with discretely variable effective piston area by means of variable circuitry of multi-chamber cylinders are discussed. Hydraulic symmetry or constant asymmetry of the hydraulic cylinder are traits of the cylinder that are required to fit the cylinder to pump structures for closed-circuit displacement control, as given in electro-hydrostatic compact drives (ECD). A methodology to generate all possible solutions of variable area cylinders under the constraint of ECD requirements is proposed.\u0000 A comprehensive description of the solution space is given, based on combinatorics and solution of equation systems. The methodology dealing with abstract cylinder areas is backed up by a general approach to describe the mechanical cylinder design space to combine multiple cylinder areas in one structural unit. Examples for design of three and four area cylinders are given and results are discussed. The paper concludes with the development of a demonstrator design to allow experimental validation in a subsequent step.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117250659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Novel Axial Piston Pump/Motor Principle With Floating Pistons: Design and Testing","authors":"Liselott Ericson, J. Forssell","doi":"10.1115/FPMC2018-8937","DOIUrl":"https://doi.org/10.1115/FPMC2018-8937","url":null,"abstract":"This paper presents the first prototype of a novel axial piston pump/motor of slipper type. The pistons are floating in the cylinders and hence the name floating piston pump. The novel pump design fills a gap in the traditional pump design. The pump is made to fit the automobile requirements to use fluid power in a more prominent manner. One of the expected benefits of this design is its simplicity and therefore the machine does not require high manufacturing capabilities. The production cost is expected to be low. The machine is designed with high number of pistons, which leads to a pump/motor with low noise level. The displacement angle is small, 8 degrees, which leads to low piston speeds with its benefits. The main challenge in the design is the piston seal configuration. The seals will both, deform (ovality) and move in a circle relative to the pistons. The paper discusses design considerations and proposes a design. The efficiency measurement of the first prototype is in level of a series produced slipper type machine at its sweet spot.","PeriodicalId":111146,"journal":{"name":"BATH/ASME 2018 Symposium on Fluid Power and Motion Control","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115202411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}