scholarly journals Investigation of fluid delivery and trapped volume performances of Truninger gear pump by a discretization approach

2016 ◽  
Vol 8 (10) ◽  
pp. 168781401667236 ◽  
Author(s):  
Wei Song ◽  
Yinglong Chen ◽  
Hua Zhou
Keyword(s):  
Gear Pump ◽  
Fluid Delivery

Theoretical flowrate characteristics of the conjugated involute internal gear pump

2012 ◽  
Vol 227 (4) ◽  
pp. 730-743 ◽  
Author(s):  
Hua Zhou ◽  
Wei Song
Keyword(s):  
Control Volume ◽  
Design Parameters ◽  
Gear Pump ◽  
Fluid Delivery ◽  
Delivery Performance ◽  
Gear Pumps ◽  
Tooth Number ◽  
Internal Gear ◽  
Double Envelope ◽  
Control Volume Approach

The aim of this article is to study the theoretical flowrate characteristics of the conjugated involute internal gear pump. The conjugated involute internal gear pump has a different internal gear, the profile of which is completely conjugated to that of pinion, from the conventional involute internal gear pump. To describe briefly, the former pump is called ‘conjugated pump’ while the latter pump ‘conventional pump’. This structure makes the conjugated pump have smaller volumes of trapped fluid than the conventional pump, which indicates the conjugated pump has a better flowrate performance. Although there have been numerous investigations into gear pumps, none of them have dealt with the conjugated pumps yet. This article presents a systematic study on the theoretical flowrate characteristics of the conjugated pumps. It is expected to obtain some generalized conclusions to guide the design of internal gear pumps. Firstly, a double envelope concept is applied to derive the mathematical models of the conjugated involute internal gear couple. Next, mesh characteristics of the gear couple, which mainly decide the fluid delivery performance of the pumps, are analyzed. Finally, using a control volume approach, the theoretical flowrate characteristics of the pump under different design parameters of gears are investigated. Results show the conjugated pump has a better performance than the conventional one. To design a conjugated pump with good flowrate characteristics, it’s feasible to choose a proper shifting coefficient, a larger tooth number of the pinion, a smaller tooth number of the internal gear, a larger pressure angle and a larger fillet radius, under the condition that no tooth interference occurs.

Causes of gear pump fails and methods for their elimination

2020 ◽  
pp. 98-107
Author(s):  
Vitaliy A. Zuyevskiy ◽  
Daniil O. Klimyuk ◽  
Ivan A. Shemberev
Keyword(s):  
Adhesion Strength ◽  
Production Systems ◽  
Low Cost ◽  
High Strength ◽  
Strength Properties ◽  
Research Purpose ◽  
Working Fluid ◽  
Gear Pump ◽  
Repair Service ◽  
Recovery Method

Gear pumps are an important element of many production systems and their replacement in case of failure can be quite expensive, so it is important to have a modern and well-tuned technology for their recovery. There are many methods for restoring the pump's performance, depending on the reason that led to its failure. (Research purpose) The research purpose is in determining what causes most often lead to loss of pump performance, and developing a recovery method that provides the greatest post-repair service life of the pump and low cost of repair. (Materials and methods) Authors took into account that the applied coatings must have sufficient adhesion strength and resistance to mechanical, thermal and corrosion loads during operation. It was found that most often significant leaks of the working fluid, leading to failure, occur due to an increase in the gap between the inner surface of the housing and the gears due to active wear of the housing wells. Authors determined that the method of electric spark treatment of worn-out housing wells is best suited to perform the task (a large post-repair resource and low costs). (Results and discussion) It was found by laboratory studies of the adhesion strength of electric spark coatings with various electrodes that the best transfer of the material to the substrate is provided by bronze electrodes BrMKts3-1. It was noted that the coatings applied using the BrMKts3-1 electrode have high strength properties. (Conclusions) Research conducted in the center for collective use "Nano-Center" VIM confirmed the possibility of effective recovery of the gear pump by electric spark treatment.

Fully Automated Parallel Oligonucleotide Synthesizer

2001 ◽  
Vol 66 (8) ◽  
pp. 1299-1314 ◽  
Author(s):  
Michal Lebl ◽  
Christine Burger ◽  
Brett Ellman ◽  
David Heiner ◽  
Georges Ibrahim ◽  
...  
Keyword(s):  
Solid Phase ◽  
Building Blocks ◽  
Solid Support ◽  
Continuous Operation ◽  
Gear Pump ◽  
Oligonucleotide Synthesis ◽  
Center Of Rotation ◽  
Microtiter Plates ◽  
The Individual ◽  
Design And Construction

Design and construction of automated synthesizers using the tilted plate centrifugation technology is described. Wash solutions and reagents common to all synthesized species are delivered automatically through a 96-channel distributor connected to a gear pump through two four-port selector valves. Building blocks and other specific reagents are delivered automatically through banks of solenoid valves, positioned over the individual wells of the microtiterplate. These instruments have the following capabilities: Parallel solid-phase oligonucleotide synthesis in the wells of polypropylene microtiter plates, which are slightly tilted down towards the center of rotation, thus generating a pocket in each well, in which the solid support is collected during centrifugation, while the liquid is expelled from the wells. Eight microtiterplates are processed simultaneously, providing thus a synthesizer with a capacity of 768 parallel syntheses. The instruments are capable of unattended continuous operation, providing thus a capacity of over two millions 20-mer oligonucleotides in a year.

scholarly journals Parameterization, Modeling, and Validation in Real Conditions of an External Gear Pump

2021 ◽  
Vol 13 (6) ◽  
pp. 3089
Author(s):  
Miquel Torrent ◽  
Pedro Javier Gamez-Montero ◽  
Esteban Codina
Keyword(s):  
Working Conditions ◽  
Test Bench ◽  
Fluid Dynamic ◽  
Graph Model ◽  
Field Tests ◽  
Black Box ◽  
Gear Pump ◽  
Volumetric Behavior ◽  
External Gear Pump ◽  
Standard Tests

This article presents a methodology for predicting the fluid dynamic behavior of a gear pump over its operating range. Complete pump parameterization was carried out through standard tests, and these parameters were used to create a bond graph model to simulate the behavior of the unit. This model was experimentally validated under working conditions in field tests. To carry this out, the pump was used to drive the auxiliary movements of a drilling machine, and the experimental data were compared with a simulation of the volumetric behavior under the same conditions. This paper aims to describe a method for characterizing any hydrostatic pump as a “black box” model predicting its behavior in any operating condition. The novelty of this method is based on the correspondence between the variation of the parameters and the internal changes of the unit when working in real conditions, that is, outside a test bench.

scholarly journals Psychoacoustic Evaluation of Hydraulic Pumps

2021 ◽  
Vol 13 (13) ◽  
pp. 7320
Author(s):  
Tobias Pietrzyk ◽  
Markus Georgi ◽  
Sabine Schlittmeier ◽  
Katharina Schmitz
Keyword(s):  
Sound Pressure ◽  
Paired Comparison ◽  
Hydraulic Drive ◽  
Operating Parameter ◽  
Gear Pump ◽  
Hydraulic Systems ◽  
Hydraulic Pump ◽  
Listening Tests ◽  
Internal Gear ◽  
Axial Piston

In this study, sound measurements of an axial piston pump and an internal gear pump were performed and subjective pleasantness judgements were collected in listening tests (to analyze the subjective pleasantness), which could be seen as the inverse of the subjective annoyance of hydraulic drives. Pumps are the dominant sound source in hydraulic systems. The noise generation of displacement machines is subject of current research. However, in this research only the sound pressure level (SPL) was considered. Psychoacoustic metrics give new possibilities to analyze the sound of hydraulic drive technology and to improve the sound quality. For this purpose, instrumental measurements of the acoustic and psychoacoustic parameters are evaluated for both pump types. The recorded sounds are played back to the participants in listening tests. Participants evaluate them regarding the subjective pleasantness by means of paired comparison, which is an indirect scaling method. The dependence of the subjective pleasantness on speed and pressure was analyzed for both pump types. Different regression analyses were carried out to predict the subjectively perceived pleasantness or annoyance of the pumps. Results show that a lower speed is the decisive operating parameter for reducing both the SPL and the annoyance of a hydraulic pump.

Safety Management of Dialysis Fluid in Japan: Important Duties and Responsibilities of Clinical Engineers

2021 ◽  
pp. 1-6
Author(s):  
Masanori Shibata
Keyword(s):  
Renal Failure ◽  
Safety Management ◽  
Standard Procedure ◽  
Medical Personnel ◽  
Maintenance Hemodialysis ◽  
Dialysis Fluid ◽  
Fluid Delivery ◽  
Technical Ability ◽  
Number Of Patients ◽  
Clinical Engineers

Dialysis therapy is the predominant choice for renal failure in Japan, and almost 30% of the patients with renal failure have been treated for 10 years or more. Dialysis became the standard procedure to treat renal failure nationwide in the 1980s. However, at that time, managing the increased number of patients on maintenance hemodialysis as well as operating and maintaining the newly developed advanced medical technologies at extensive numbers of clinical sites proved problematic. To help address this, the clinical engineer system was established in 1987 and certain aspects of the clinical engineers’ role remain unique to Japan today. For the last 30 years, clinical engineers have worked as frontline medical personnel not only operating dialysis-related devices but also placing their hands directly on patients when providing care, routinely performing puncture, and administering drugs through the blood circuit under physicians’ instructions. As part of their work, they crucially maintain the use of central dialysis fluid delivery systems (CDDSs) – also unique to Japan – which prepare and deliver a large quantity of dialysis fluid through a central circuit to individual dialysis consoles. CDDSs are widely used because they effectively alleviated the early confusion at clinical sites caused by the rapidly increasing hemodialysis population and the serious shortage in medical personnel. Moreover, clinical engineers alone have the technical ability to provide safe dialysis fluids adjusted to strict standards at clinical sites. In this review article, we focus on the crucial roles that clinical engineers have in maintaining the safety of dialysis-related medical devices and the preparation and delivery of dialysis fluid at many dialysis facilities across the country.

Nonosmotic release of vasopressin and renal aquaporins in impaired urinary dilution in hypothyroidism

2005 ◽  
Vol 289 (4) ◽  
pp. F672-F678 ◽  
Author(s):  
Yung-Chang Chen ◽  
Melissa A. Cadnapaphornchai ◽  
Jianhui Yang ◽  
Sandra N. Summer ◽  
Sandor Falk ◽  
...  
Keyword(s):  
Protein Expression ◽  
Renal Cortex ◽  
Free Water ◽  
Urine Osmolality ◽  
Protein Abundance ◽  
Oral Gavage ◽  
Water Excretion ◽  
Urinary Osmolality ◽  
Water Load ◽  
Fluid Delivery

The purpose of this study was to examine protein expression of renal aquaporins (AQP) and ion transporters in hypothyroid (HT) rats in response to an oral water load compared with controls (CTL) and HT rats replaced with l-thyroxine (HT+T). Hypothyroidism was induced by aminotriazole administration for 10 wk. Body weight, water intake, urine output, solute and urea excretion, and serum and urine osmolality were comparable among the three groups at the conclusion of the 10-wk treatment period. One hour after oral gavage of water (50 ml/kg body wt), HT rats demonstrated significantly less water excretion, higher minimal urinary osmolality, and decreased serum osmolality compared with CTL and HT+T rats. Despite the hyposmolality, plasma vasopressin concentration was elevated in HT rats. These findings in HT rats were associated with an increase in protein abundance of renal cortex AQP1 and inner medulla AQP2. AQP3, AQP4, and the Na-K-2Cl cotransporter were also increased. Moreover, 1 h following the oral water load, HT rats demonstrated a significant increase in the membrane-to-vesicle fraction of AQP2 by Western blot analysis. The defect in urinary dilution in HT rats was reversed by the V2 vasopressin antagonist OPC-31260. In conclusion, impaired urinary dilution in HT rats is primarily compatible with the nonosmotic release of vasopressin and increased protein expression of renal AQP2. The impairment of maximal solute-free water excretion in HT rats, however, appears also to involve diminished distal fluid delivery.

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