Multi-parameter load sensing pump model simulation and flow rate characteristics research

This paper aimed to analyze the influence of drivers’ behavior of phone use while driving on traffic flow, including both traffic efficiency and traffic safety. An improved cellular automaton model was proposed to simulate traffic flow with distracted drivers based on the Nagel-Schreckenberg model. The driving characters of drivers using a phone were first discussed and a value representing the probability to use a phone while driving was put into the CA model. Simulation results showed that traffic flow rate was significantly reduced if some drivers used a phone compared to no phone use. The flow rate and velocity decreased as the proportion of drivers using a phone increased. While, under low density, the risk of traffic decreased first and then increased as the distracted drivers increased, the distracted behavior of drivers, like using a phone, could reduce the flow rate by 5 percent according to the simulation.

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Lattice Boltzmann Simulations of Bubble Dynamics at the Anode of a µDMFC

3rd International Conference on Fuel Cell Science, Engineering and Technology ◽

10.1115/fuelcell2005-74070 ◽

2005 ◽

Author(s):

Kai Fei ◽

Chin-Hsien Cheng ◽

Che-Wun Hong

Keyword(s):

Pore Size ◽

Flow Rate ◽

Diffusion Layer ◽

Lattice Boltzmann ◽

Stream Flow ◽

Bubble Dynamics ◽

Model Simulation ◽

Solid Wall ◽

Two Phase ◽

Flow Channels

This paper presents the bubble transport phenomenon at the anode of a micro direct methanol fuel cell (μDMFC) from a messooscopic viewpoint. Carbon dioxide bubbles generated at the anode may block part of the catalyst/diffusion layer and also the flow channels that cause the μDMFC malfunction. Lattice-Boltzmann methods (LBM) were employed in this paper to simulate the two phase flow in a simplified micro channel which emulates the bubble dynamics in the porous diffusion layer and the flow channel. A two-dimensional, nine velocity model (D2Q9) was established. The surface tension, buoyancy force were treated as source terms in the momentum equation. Bounce back boundary conditions were assumed at the fluid-solid interface in this model. Simulation results and parametric studies showed that the pore size, the stream flow rate and the hydrophilic effect between the fluid and the solid wall play the major roles in the bubble dynamics. Larger pore size, higher methanol stream flow rate and greater hydrophilicity are preferred for bubble removal at the anode diffusion layer and also the flow channels.

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Proposal of a Load Sensing Two-Way Valve Model, Applying “Design of Experiments” Techniques to Simulations

Fluid Power Systems and Technology ◽

10.1115/imece2006-13681 ◽

2006 ◽

Author(s):

Andrea Vacca

Keyword(s):

Design Of Experiments ◽

Analytical Model ◽

Flow Rate ◽

Operating Conditions ◽

Fractional Factorial ◽

Geometrical Parameters ◽

Screening Analysis ◽

Load Sensing ◽

Actual Behaviour ◽

Wide Range

This paper defines an analytical model, based on results of simulations, for the description of the actual behaviour of a particular load sensing valve. The component considered for the analysis is typically applied in steering systems, with a load sensing control strategy, in presence of other actuators. Controlling the primary port flow rate is the valve's scope, the exceeding flow being discharged to the secondary port. A simple analytical model of the valve is commonly used in the industrial field and is useful for the understanding of its operation in a generic hydraulic system. However, experiments show that the actual behaviour is strongly influenced by the flow rate through the valve, and depends also on many geometrical parameters (i.e. shape of spool grooves, spool edges distance, etc.). The simple empirical model presented in this paper is defined considering only parameters primarily affecting the valve operation. As it often happens in searching for new models, the discovery of the most influencing factors presents several difficulties, because of their large number and, mainly, because it is difficult to consider all possible mutual interactions. Therefore, in this analysis, a stochastic-based method has been chosen, according to a technique known as "Design of Experiments" (DOE). In the first part of the paper, the author presents a screening analysis of the valve, under all the possible operating conditions. This procedure allows the identification of the most influencing parameters, for the development of the enhanced model of the valve. The configurations examined were chosen defining an optimal experimental plan, that allows an high significance of results with a restricted number of tests, through fractional factorial strategies. Further, this analysis gives a lot of useful information for the improvement of the valve design. In the remaining section of this paper, the author presents a correlative model of actual valve behaviour. This is generalized to a wide range of possible spool geometries, and is characterized by a simple formulation, accounting for only a few parameters, highlighted by the screening analysis. All results processed by DOE algorithms, implemented with MATLAB® scripts, are evaluated through simulations, instead of experiments. For this purpose, a previously developed AMESim® model of the valve (validated on the basis of laboratory tests) has been utilized.

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Model Simulation of Heat and Water Transport Dynamics in an Airway

Journal of Biomechanical Engineering ◽

10.1115/1.3138404 ◽

1983 ◽

Vol 105 (2) ◽

pp. 188-193 ◽

Cited By ~ 10

Author(s):

G. M. Saidel ◽

K. L. Kruse ◽

F. P. Primiano

Keyword(s):

Water Transport ◽

Flow Rate ◽

Velocity Gradient ◽

Model Simulation ◽

Physiological State ◽

Transport Processes ◽

Gas Temperature ◽

Breathing Patterns ◽

Transport Dynamics

Heat and water transport processes in the respiratory tract depend on environmental conditions, breathing patterns, and the physiological state of the respiratory system. To study these processes, we have developed a mathematical model of the dynamics of temperature and water vapor in the radial and axial directions of an idealized trachea. The model is expressed as two implicit finite-difference equations and solved using an alternating-direction algorithm. Using these equations, we simulated the effects of inspired gas temperature and humidity, velocity profile, and flow rate on heat and water transport between the gas and airway wall. Under inspired gas conditions of low temperature or high relative humidity, supersaturation occurs. Increasing either the velocity gradient at the wall or the flow rate increases the heat and water transport rates. However, these rates change by only 10 percent when the velocity gradient is doubled, and by about 35 percent when flow rate undergoes a two-fold change. The model can be used with in-vivo data from the trachea to test hypotheses concerning normal and abnormal heat and water transport.

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MODELAGEM DA REDUÇÃO DE VAZÃO EM PARCELAS DE IRRIGAÇÃO DEVIDO AO INCREMENTO DA PERDA DE CARGA DO SISTEMA DE FILTRAGEM

Irriga ◽

10.15809/irriga.2016v21n3p425-437 ◽

2018 ◽

Vol 21 (3) ◽

pp. 425

Author(s):

Marinaldo Ferreira Pinto ◽

Dinara Grasiela Alves ◽

Ezequiel Saretta ◽

Tarlei Arriel Botrel

Keyword(s):

Flow Rate ◽

Model Simulation ◽

Maximum Flow ◽

Head Loss ◽

Pump System ◽

Pumping System ◽

Total Head ◽

System 2 ◽

Line Pressure ◽

E Mail

MODELAGEM DA REDUÇÃO DE VAZÃO EM PARCELAS DE IRRIGAÇÃO DEVIDO AO INCREMENTO DA PERDA DE CARGA DO SISTEMA DE FILTRAGEM MARINALDO FERREIRA PINTO1; DINARA GRASIELA ALVES1; EZEQUIEL SARETTA2 E TARLEI ARRIEL BOTREL3 1Departamento de Engenharia, Instituto de Tecnologia, UFRRJ, Rodovia BR 465, km 7, 23890-000, Seropédica, Rio de Janeiro, Brasil, e-mail: [email protected], [email protected] Acadêmica do Campus Cachoeira do Sul da UFSM, CEP 96506-322, Cachoeira do Sul, RS. E-mail: [email protected] de Engenharia de Biossistemas, ESALQ/USP, Avenida Pádua Dias, 11, 13418-900, Piracicaba, São Paulo, Brasil, e-mail: [email protected] 1 RESUMO A perda de carga nos filtros pode alterar a altura manométrica total de um sistema de bombeamento e consequentemente a pressão na entrada das parcelas de irrigação, podendo comprometer a uniformidade de aplicação e lâmina de irrigação. O objetivo deste trabalho foi desenvolver um modelo para simulação do efeito do incremento da perda de carga no sistema de filtragem na vazão de uma parcela de irrigação. Foram consideradas duas situações: a) o sistema de bombeamento apresenta um dispositivo para regulação da altura manométrica total; e b) o sistema de bombeamento não dispõe de tal recurso. Analisou-se diferentes valores de expoente de vazão dos emissores, diâmetros e/ou comprimentos de adutoras, pressão de trabalho e incremento da perda de carga no sistema de filtragem. Foram considerados uma motobomba com vazão nominal de 10 m3 h-1 e um sistema de filtragem com vazão nominal de 2 m3 h-1. A partir das simulações foi possível se determinar o limite de incremento da perda de carga que proporciona uma redução de vazão máxima admitida para cada cenário avaliado. Esses valores foram comparados com a perda de carga máxima admitida, sendo adotado o menor valor de perda de carga, entre esses dois critérios. PALAVRAS-CHAVE: modelo hidráulico; simulação; microirrigação PINTO, M. F.; ALVES, D. G.; SARETTA, E.; BOTREL, T. A.AN APPROACH FOR FLOW REDUCTION OF IRRIGATION BLOCKS DUE TO INCREASING HEAD LOSS OF THE FILTERING SYSTEM 2 ABSTRACT The head loss in filters can change the total head of the pump system and consequently the pressure on the irrigation block inlet. It may compromise the uniformity of application and the irrigation depth. The aim of this study was to develop a model to simulate the effect of head loss increasing of filtering system on the flow of an irrigation block. It considered two situations: a) pumping system with a device for regulating the total head; and, b) pumping without system for regulating the total head. We analyzed different values of exponent flow emitters, diameters and/or lengths of main line, pressure and head loss increasing in the filtering system. It considered a pump with nominal flow rate of 10 m3 h-1 and a filtering system with nominal flow rate of 2 m3 h-1. From the simulations, it was possible to determine the limit of head loss increasing that provides a range of maximum flow allowed for each scenario. These values were compared with the maximum permissible head loss, and adopted the lower value of head loss, between these two criteria. Keywords: hydraulics model; simulation; microirrigation

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Dynamic Model Simulation and Verification of a Two-Stage High-Rate Anaerobic Treatment Process with Recycle

Water Science & Technology ◽

10.2166/wst.1993.0659 ◽

1993 ◽

Vol 28 (11-12) ◽

pp. 197-207 ◽

Cited By ~ 2

Author(s):

J. Keller ◽

M. Romli ◽

P. L. Lee ◽

P. F. Greenfield

Keyword(s):

Sodium Hydroxide ◽

Flow Rate ◽

Gas Flow ◽

Model Simulation ◽

Anaerobic Treatment ◽

High Rate ◽

Continuous Reactor ◽

Feed Concentration ◽

Two Phase ◽

Significant Discrepancy

The effect of overload on a two-phase high rate anaerobic wastewater treatment system with recycle was determined experimentally and simulated dynamically using a structured model. The experimental system consisted of a well mixed continuous reactor, controlled at pH 6 by sodium hydroxide addition, as the acidification stage and a fluidized bed reactor for the methanogenic stage, with an additional recycle connection from the second to the first reactor. Step changes in the feed concentration as well as in the feed flow rate were investigated and compared to simulation predictions. Operation without recycle was modelled accurately, with the simulation data of most process variables matching the experimental results quantitatively. The application of the same model to recycle operation showed significant discrepancy between the experimental and simulated data for the sodium hydroxide consumption rate and the gas flow rate in the acidification reactor. Although the actual values were different, the qualitative responses of the experimental and simulated step changes were similar. Other simulated variables showed good agreement with the experimental measurements. The model provides a useful tool for design and control studies in systems without recycle and, with some modification, for operation with recycle.

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Simulation and Analysis on Load-Sensing Swash Plate Piston Pumps Based on AMESim

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.631-632.723 ◽

2014 ◽

Vol 631-632 ◽

pp. 723-727 ◽

Cited By ~ 1

Author(s):

Lan Tang ◽

Zhuo Qing Li ◽

Tao Tao Gao

Keyword(s):

Flow Rate ◽

Rotation Speed ◽

Steering System ◽

Piston Pump ◽

Load Sensing ◽

Swash Plate ◽

Set Up ◽

Different Parts

Relations between different parts are analyzed based on the structure of load-sensing swash plate piston pump. The models of piston pump and the servomechanism are set up by AMESim and connected with load-sensing steering system. The pressure and flow rate response under different rotation speed without priority valve is researched. The result shows such piston pump model can always response quickly and provide reasonable pressure and flow rate that fit the steering demands.

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Study on the System Characteristic of a Crane Walking Hydraulic System Based on AMESim

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.430-432.1809 ◽

2012 ◽

Vol 430-432 ◽

pp. 1809-1813

Author(s):

Li Li ◽

Xiao Qiang Wu ◽

Hua Yang Zhao ◽

Xiao Min Shan

Keyword(s):

Hydraulic System ◽

Simulation Analysis ◽

Model Simulation ◽

Simulation Software ◽

Analysis Method ◽

Load Sensing ◽

System A ◽

Change Characteristics ◽

Multidisciplinary Simulation ◽

Crawler Crane

A system simulation model is established by multidisciplinary simulation software Amesim. This model is on account of travel system of a certain hydraulic crawler crane, mainly on selector valve and load sensing pump. Based on this model simulation and dynamic analysis is carried out, then output volume change characteristics of load sensing pump along with load changes is got. Contrasting the simulation result and experiment result, correspondence is very good， which indicate that this model and related parameters are in accordance with real system. A simulation analysis method used to analysis changes of load sensing pump along with load changes is provided.

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A Novel Reconstitution Method for Inducing the Formation of Regular 2-Dimensional Arrays of Membrane Proteins and Lipids

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102845 ◽

1988 ◽

Vol 46 ◽

pp. 152-153 ◽

Cited By ~ 1

Author(s):

A. Engel ◽

A. Holzenburg ◽

K. Stauffer ◽

J. Rosenbusch ◽

U. Aebi

Keyword(s):

Membrane Proteins ◽

Flow Rate ◽

Lipid Membranes ◽

Functional Characterization ◽

Dimensional Structure ◽

Electron Crystallography ◽

Peltier Element ◽

Protein Ratio ◽

Precise Control ◽

3 Dimensional

Reconstitution of solubilized and purified membrane proteins in the presence of phospholipids into vesicles allows their functions to be studied by simple bulk measurements (e.g. diffusion of differently sized solutes) or by conductance measurements after transformation into planar membranes. On the other hand, reconstitution into regular protein-lipid arrays, usually forming at a specific lipid-to-protein ratio, provides the basis for determining the 3-dimensional structure of membrane proteins employing the tools of electron crystallography.To refine reconstitution conditions for reproducibly inducing formation of large and highly ordered protein-lipid membranes that are suitable for both electron crystallography and patch clamping experiments aimed at their functional characterization, we built a flow-dialysis device that allows precise control of temperature and flow-rate (Fig. 1). The flow rate is generated by a peristaltic pump and can be adjusted from 1 to 500 ml/h. The dialysis buffer is brought to a preselected temperature during its travel through a meandering path before it enters the dialysis reservoir. A Z-80 based computer controls a Peltier element allowing the temperature profile to be programmed as function of time.

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Novel epoxy/anhydride alternatives for biological electron microscopy: Physical and performance characteristis of embed 812 and LX 112 in combination with NSA/NMA/DMAE

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156985 ◽

1989 ◽

Vol 47 ◽

pp. 1000-1001

Author(s):

Joe A. Mascorro ◽

Gerald S. Kirby

Keyword(s):

Electron Microscopy ◽

Flow Rate ◽

Succinic Anhydride ◽

Volume Flow Rate ◽

Mass Density ◽

Uranyl Acetate ◽

Volume Flow ◽

Base Resin ◽

And Performance ◽

Acid Anhydrides

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.

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