A Three-Dimensional CFD Methodology to Study Vane-Ring and Vane-Under-Vane Interactions of a Vane Pump Power Split Transmission

2016 ◽  
Author(s):  
Emma Frosina ◽  
Adolfo Senatore ◽  
Dario Buono ◽  
Kim A. Stelson ◽  
Feng Wang ◽  
...  
Keyword(s):  
Pump Power ◽  
Model Building ◽  
Three Dimensional ◽  
Output Shaft ◽  
University Of Minnesota ◽  
Hydraulic Motor ◽  
Vane Pump ◽  
Input Shaft ◽  
Power Split ◽  
The University

This paper presents a study of a novel vane pump power split transmission (VPPST). The transmission incorporates a new component, the Vane Power Split Unit (VPSU). The VPSU is a double-acting vane pump with a floating ring where the input shaft is connected to the engine and the floating ring is connected to the output shaft. The VPSU generates hydraulic oil flow at a rate proportional to the difference in angular velocities between the input and output shafts. This flow enters a hydraulic motor mounted to the output shaft. The vane pump power split transmission (VPPST) is a combination of the double-acting vane pump (VPSU) and the hydraulic motor directly connected to the pump. A CFD model of the VPSU has been created to better understand its performance. The model uses the three-dimensional CFD commercial code PumpLinx®, developed by Simerics® Inc. Thanks to collaboration with the code developers, the model is able to predict the complex fluid dynamics in the pockets in the rotor into which the vanes retract. These pockets are referred to as under-vane volumes. The rotor of the vane pump, in fact, has several internal channels that connect the pumping chambers between the vanes to the under-vane volumes. The combination of the vanes and the internal ducts and volumes of the under-vanes have been modelled as dynamic “valves” that rotate with the rotor. In this way the radial movements of the vanes are computed as a part of the simulation, based on the pressures due to the compression of the volumes on the inner diameter side of the vanes. The study is a result of collaboration between the University of Minnesota and the University of Naples “Federico II” research groups and the code developers of Simerics® Inc. The universities and Simerics® Inc. have all been involved in this project, working in close cooperation for the model building and simulations.

Vane Pump Power Split Transmission: Three Dimensional Computational Fluid Dynamics Modeling

2015 ◽  
Author(s):  
Emma Frosina ◽  
Adolfo Senatore ◽  
Dario Buono ◽  
Kim A. Stelson ◽  
Feng Wang ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Pump Power ◽  
Three Dimensional ◽  
University Of Minnesota ◽  
Dynamics Modeling ◽  
Vane Pump ◽  
Hydraulic Test ◽  
Pump Operation ◽  
Power Split ◽  
The University

A three dimensional CFD analysis of a novel vane pump power split transmission is studied in this paper. The model was built using PumpLinx®, a three-dimensional CFD commercial code developed by Simerics Inc.® The Mathers Hydraulics® vane pump is a double-acting vane pump with a floating ring. By coupling the floating ring to an output shaft, the vane pump becomes a hydrostatic transmission. The focus of this activity is the optimization of the vane pump analyzing the internal fluid dynamics of each part during the pump operation and redesign. The study is a result of collaboration between the University of Minnesota and the University of Naples “Federico II” research groups. The universities involved in this project worked in close cooperation on these simulations. A prototype pump will be tested on a hydraulic test bench at the University of Minnesota, and the experimental data will be used to validate the simulation model.

Performance Study of Vane Pump Power Split Transmission for a Highway Vehicle

2015 ◽  
Author(s):  
Biswaranjan Mohanty ◽  
Feng Wang ◽  
Kim A. Stelson
Keyword(s):  
Pump Power ◽  
Continuous Variable ◽  
Control Flow ◽  
Output Shaft ◽  
Performance Study ◽  
Hydraulic Motor ◽  
Vane Pump ◽  
Engine Operation ◽  
Power Split ◽  
Variable Displacement

A novel Vane Pump Power Split Transmission (VPPST), applied to a class 1 pickup truck, is demonstrated in this paper. The VPPST, a power split hydraulic transmission consists of Vane Pump Power Split Unit (VPSU) and a variable displacement hydraulic motor. The VPSU is a double acting vane pump with a floating ring. The floating ring is coupled to the output shaft, which is connected to the drive shaft. The input shaft of the VPSU is coupled to the engine. The control flow of the VPSU is fed to a variable displacement motor mounted on the VPSU output shaft. The transmission ratio is adjusted by controlling the displacement of the variable motor. The resulting continuous variable transmission allows for optimum engine operation by decoupling the engine speed from the drive speed. The transmission also has an integral clutch that allows de-clutching the engine from the drive train by retracting the vanes of the VPSU. In this paper, a quasi-static simulation approach is used to study the performance of the transmission.

Modeling and Experimental Study of a Novel Power Split Hydraulic Transmission

2018 ◽  
Author(s):  
Haoxiang Zhang ◽  
Feng Wang ◽  
Bing Xu
Keyword(s):  
Flow Rate ◽  
Experimental Studies ◽  
Friction Torque ◽  
Output Shaft ◽  
Mechanical Power ◽  
Vane Pump ◽  
Input Shaft ◽  
Power Split ◽  
Outlet Flow ◽  
Shaft Torque

The characteristics of a novel power split hydraulic transmission are studied in this paper. The new hydraulic transmission is built from a balanced vane pump with a floating ring. By coupling the floating ring to the output shaft, it becomes a hydraulic transmission, converting the mechanical power on the input shaft into the hydraulic power at the outlet and the mechanical power on the output shaft. By controlling the pressure at the outlet (control pressure), the power ratio transferred through mechanical and hydraulic path can be adjusted. One important feature of the new transmission is that the internal friction torque of the transmission, e.g., friction torque between vane tips and floating ring, helps to drive the output shaft whereas is wasted and turned into heat in a conventional vane pump. This increases the transfer efficiency from input shaft to output shaft. In this study, the characteristics of the input shaft torque, output shaft torque and the outlet flow rate are investigated through experimental studies. Results show that the shaft torques and the outlet flow rate are functions of control pressure and differential shaft speed. The mathematical models have been developed from the analytical and experimental results. The study provides a comprehensive understanding of the new transmission.

scholarly journals Peppy

2020 ◽  
Vol 2 (1) ◽  
pp. 49-50
Author(s):  
David Doak ◽  
Gareth Denyer ◽  
Juliet Gerrard ◽  
Joel Mackay ◽  
Jane Allison
Keyword(s):  
Virtual Reality ◽  
Secondary Structure ◽  
Degrees Of Freedom ◽  
Model Building ◽  
Three Dimensional ◽  
Protein Secondary Structure ◽  
Peptide Backbone ◽  
Molecular Forces ◽  
And Function ◽  
The University

Science students are traditionally taught protein structure and function through textbook pictures and/or physical model building. This is not effective for most students because conceiving large, complex three-dimensional chemicals structure and dynamic molecular interactions requires a very high degree of abstract thought, imagination and extrapolation. It is intuitively reasonable to believe that a virtual reality approach would aid appreciation of nanoscale molecular structure, function and dynamics. I will describe the Virtual Reality (VR) tool, “Peppy” (1), that we have developed for exploring the molecular forces which drive protein secondary structure. Peppy allows students to build, visualise and manipulate polypeptides within the six degrees of freedom that characterises the VR environment. Peppy not only recreates traditional secondary structures dependent on hydrogen- bonding in a generic peptide backbone, it also permits students to insert any and all of the 20 amino acids and to examine the effect of the shapes and electrostatic forces of these on secondary structure. The highly extrapolative environment created by Peppy is extended with features that encourage student engagement, such as a selfie camera, interactive Ramachandran plot, and even features to emphasise the dynamics of a vibrant macromolecular structure. Being able to physically and directly grab and manipulate the atoms and angles with the virtual hand enhances the connection of students with the molecules and results in an exploration experience unmatched by traditional 3D visualisation software. I will also describe the testing and iterative improvement of Peppy during deployment to large undergraduate classes at the University of Sydney, which boasts the Immersive Learning Lab, with 26 VR (Oculus Rift) headsets. Remarkably, even students with no prior VR experience are able to interact with Peppy in an engaged and meaningful way within just 10 minutes and, after less than an hour many are able to build highly complex multi-peptide structures such as β-barrels or experiment with long peptides containing a variety of side chains and disulphide bonds. The experience resonates with the students well after the session, as evidenced by their reflections and follow-up questions regarding the physics of the simulation and ideas for extension of the software.

A Novel Pressure-Controlled Hydro-Mechanical Transmission

2014 ◽  
Author(s):  
Feng Wang ◽  
Kim A. Stelson
Keyword(s):  
Fundamental Principle ◽  
Transmission Efficiency ◽  
Control Flow ◽  
Drive System ◽  
Output Shaft ◽  
Mechanical Transmission ◽  
Hydraulic Motor ◽  
Vane Pump ◽  
Variable Displacement ◽  
Pressure Controlled

A novel pressure-controlled hydro-mechanical transmission (PHMT) is studied in this paper. The PHMT consists of a pressure-controlled hydraulic transmission (PCT) and a variable displacement hydraulic motor. The PCT functions like a conventional hydrostatic transmission (HST) but has a different form. It uses a double-acting vane pump with a floating ring. By coupling the floating ring to an output shaft, the vane pump becomes a hydraulic transmission. The PCT combines the pumping and motoring functions in one unit, making it much simpler than a conventional HST. By controlling the pressure in the PCT, the output shaft torque and speed can be adjusted. By feeding the PCT control flow to a variable displacement motor coupled to the PCT output shaft, a PHMT is constituted. In this paper, the fundamental principle of the PHMT is studied. To demonstrate its advantage, the PHMT is applied to a fan drive system and the transmission efficiency is compared to a conventional HST. Preliminary experimental results show that the input power of the fan drive system with a PHMT is lower than that with an HST given the same output fan speed and torque.

scholarly journals The first protein Structure Determinations

2014 ◽  
Vol 70 (a1) ◽  
pp. C1801-C1801
Author(s):  
Michael Rossmann
Keyword(s):  
Heavy Atom ◽  
Three Dimensional ◽  
Three Dimensions ◽  
University Of Minnesota ◽  
Phase Determination ◽  
Metal Compounds ◽  
Replacement Method ◽  
Isomorphous Replacement ◽  
Structure Determinations ◽  
The University

Max Perutz had been studying the structure of haemoglobin for 21 years using highly original and creative techniques, when I arrived in Cambridge in the summer of 1958. Most recently he had explored the use of isomorphous replacement by substituting specific amino acids with heavy metal compounds. Together with Ann Cullis, he had collected three dimensional diffraction data on native haemoglobin crystals and on three heavy atom derivatives. But now Max needed help in analyzing this data. I had had experience in determining three small aromatic hydrocarbon structures as a graduate student with J.M. Robertson at the University of Glasgow using only mechanical hand calculators, a slide rule and Beevers-Lipson strips. At the University of Minnesota, as a post doc with Bill Lipscomb, I had learned how to program one of the earliest commercial computers and solved a plant terpenoid structure in three dimensions. Thus, when I joined Max's lab, I was soon busy programming the bran new "home build" EDSAC2 computer to determine and refine the heavy atom parameters for phase determination by isomorphous replacement. When we calculated the 5.5Å resolution horse oxy haemoglobin electron density map in the summer of 1959 we were amazed to see that the two polypeptide chains of haemoglobin each had the same fold as that of myoglobin, another oxygen carrying protein determined by John Kendrew at 6Å resolution two years earlier at the Cavendish. John and his group were extending the structure of myoglobin to 2Å resolution. The high resolution map of myglobin was calculated using my Fourier program the week after the low resolution haemoglobin map. We then saw the atomic structure of α-helices as had been predicted by Linus Pauling. Seeing evolution for the first time at a molecular level has inspired my thinking and choice of research topics ever since. In the following few years, stimulated by these discoveries , David Blow (who had returned from the US later that summer after two years of post-doc studies) and I developed the single isomorphous replacement method, the use of anomalous dispersion for phase determination, phase combination procedures and, most importantly, molecular replacement.

The Effects of Presentation on Noise and Dental Appliances on Speech

1981 ◽  
Vol 24 (1) ◽  
pp. 151-151
Author(s):  
Lillian Glass ◽  
Sharon R. Garber ◽  
T. Michael Speidel ◽  
Gerald M. Siegel ◽  
Edward Miller
Keyword(s):  
Southern California ◽  
University Of Southern California ◽  
University Of Minnesota ◽  
School Of Medicine ◽  
Southern California School ◽  
School Of Dentistry ◽  
The University

An omission in the Table of Contents, December JSHR, has occurred. Lillian Glass, Ph.D., at the University of Southern California School of Medicine and School of Dentistry, was a co-author of the article "The Effects of Presentation on Noise and Dental Appliances on Speech" along with Sharon R. Garber, T. Michael Speidel, Gerald M. Siegel, and Edward Miller of the University of Minnesota, Minneapolis.

Integrating Legacy Laboratory Information Systems into a Client-Server World: The University of Minnesota Clinical Workstation (CWS) Project

1995 ◽  
Vol 34 (03) ◽  
pp. 289-296 ◽  
Author(s):  
B. H. Sielaff ◽  
D. P. Connelly ◽  
K. E. Willard
Keyword(s):  
Information Systems ◽  
Clinical Decision ◽  
Database Management System ◽  
University Of Minnesota ◽  
Client Server ◽  
Clinical Workstation ◽  
Future Hospital ◽  
The Cost ◽  
The University ◽  
Laboratory Information Systems

Abstract:The development of an innovative clinical decision-support project such as the University of Minnesota’s Clinical Workstation initiative mandates the use of modern client-server network architectures. Preexisting conventional laboratory information systems (LIS) cannot be quickly replaced with client-server equivalents because of the cost and relative unavailability of such systems. Thus, embedding strategies that effectively integrate legacy information systems are needed. Our strategy led to the adoption of a multi-layered connection architecture that provides a data feed from our existing LIS to a new network-based relational database management system. By careful design, we maximize the use of open standards in our layered connection structure to provide data, requisition, or event messaging in several formats. Each layer is optimized to provide needed services to existing hospital clients and is well positioned to support future hospital network clients.

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