scholarly journals Use of an Inverse Method for the Design of High Efficiency Compressor and Turbine Blades With Large Change in Radius

1984 ◽  
Author(s):  
G. Meauzé ◽  
A. Lesain
Keyword(s):  
Inverse Method ◽  
High Efficiency ◽  
Radial Flow ◽  
Turbine Blades ◽  
Large Change ◽  
Airfoil Optimization ◽  
Time Marching ◽  
Flow Compressor ◽  
Compressor And Turbine Blades ◽  
Made In

Extension of the time-marching computations of flows in 2-D blade cascades to the case of cascades with variable radius and stream tube thickness. One of the specific cases analyzed is that of purely radial cascades. Direct and inverse calculations are made, in non-viscous subsonic or supersonic flows, with or without shock waves. Examples of the design of high efficiency airfoil optimization for radial flow compressor rotors or Stators or inward flow turbine inlet guide vanes are presented.

scholarly journals A Navier-Stokes Inverse Method Based on a Moving Blade Wall Strategy

1997 ◽  
Author(s):  
Olivier Léonard ◽  
Alain Demeulenaere
Keyword(s):  
Inverse Method ◽  
Stokes Equations ◽  
Turbine Blades ◽  
Time Integration ◽  
Navier Stokes ◽  
Navier Stokes Equations ◽  
Integration Schemes ◽  
Time Integration Schemes ◽  
The Difference ◽  
Compressor And Turbine Blades

A two-dimensional viscous inverse method for the design of compressor and turbine blades is presented. An initial geometry is modified iteratively to reach a target pressure distribution imposed on the blade surfaces. The Navier-Stokes equations are solved in a numerical domain of which some boundaries (the blade walls) move during the transient part of the computation. The blade modifications are based on the transpiration principle. The transpiration flux is computed from the difference between the actual and the prescribed pressure distributions. A high-resolution Navier-Stokes solver has been developed for this purpose, based on a Finite-Volume formulation. Multi-block structured grids allow for a selective concentration of discretization points in the zones of higher gradients. Both explicit (Runge-Kutta) and implicit (Newton-Krylov) time integration schemes have been implemented. Applications to turbine and compressor blade design illustrate the accuracy of the flow computation, and the efficiency of the inverse method.

A two-dimensional Navier—Stokes inverse solver for compressor and turbine blade design

1997 ◽  
Vol 211 (4) ◽  
pp. 299-307 ◽  
Author(s):  
A Demeulenaere ◽  
O Léonard ◽  
R Van den Braembussche
Keyword(s):  
Inverse Method ◽  
Stokes Equations ◽  
Turbine Blades ◽  
Navier Stokes ◽  
Normal Velocity ◽  
Blade Design ◽  
Two Dimensional ◽  
Blade Shape ◽  
The Difference ◽  
Compressor And Turbine Blades

A two-dimensional viscous inverse method for the design of compressor and turbine blades is presented. It iteratively modifies an initial geometry until a prescribed pressure distribution is reached on the blade surface. The method solves the time-dependent Navier—Stokes equations in a numerical domain of which some boundaries (the blade walls) move during the transient part of the computation. The geometry modification algorithm is based on the transpiration principle: a normal velocity distribution is computed from the difference between the actual and prescribed pressure distributions, and is used to modify the blade shape. A time iteration is then performed on this new blade shape, taking into account the grid movement during the time stepping. A two-dimensional upwind finite-volume Navier—Stokes solver has been developed. The multiblock strategy allows for a selective concentration of the discretization points in the zones of higher gradients. Applications to turbine and compressor blade design illustrate the accuracy of the flow computation, the capabilities and efficiency of the inverse method.

scholarly journals Pathogenesis and Potential Therapeutic Targets for Triple-Negative Breast Cancer

Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2978
Author(s):  
Chia-Jung Li ◽  
Yen-Dun Tony Tzeng ◽  
Yi-Han Chiu ◽  
Hung-Yu Lin ◽  
Ming-Feng Hou ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Targeted Therapy ◽  
Triple Negative Breast Cancer ◽  
Triple Negative ◽  
High Efficiency ◽  
Early Recurrence ◽  
New Developments ◽  
Great Progress ◽  
Low Toxicity ◽  
Made In

Triple negative breast cancer (TNBC) is a heterogeneous tumor characterized by early recurrence, high invasion, and poor prognosis. Currently, its treatment includes chemotherapy, which shows a suboptimal efficacy. However, with the increasing studies on TNBC subtypes and tumor molecular biology, great progress has been made in targeted therapy for TNBC. The new developments in the treatment of breast cancer include targeted therapy, which has the advantages of accurate positioning, high efficiency, and low toxicity, as compared to surgery, radiotherapy, and chemotherapy. Given its importance as cancer treatment, we review the latest research on the subtypes of TNBC and relevant targeted therapies.

New Development in High Efficiency Deep Grinding

2012 ◽  
Author(s):  
Andre D. L. Batako ◽  
Valery V. Kuzin ◽  
Brian Rowe
Keyword(s):  
Machine Tool ◽  
High Efficiency ◽  
Machining Process ◽  
Depth Of Cut ◽  
Removal Rates ◽  
Workpiece Surface ◽  
New Development ◽  
Cutting Processes ◽  
Selection Of ◽  
Made In

High Efficiency Deep Grinding (HEDG) has been known to secure high removal rates in grinding processes at high wheel speed, relatively large depth of cut and moderately high work speed. High removal rates in HEDG are associated with very efficient grinding and secure very low specific energy comparable to conventional cutting processes. Though there exist HEDG-enabled machine tools, the wide spread of HEDG has been very limited due to the requirement for the machine tool and process design to ensure workpiece surface integrity. HEDG is an aggressive machining process that requires an adequate selection of grinding parameters in order to be successful within a given machine tool and workpiece configuration. This paper presents progress made in the development of a specialised HEDG machine. Results of HEDG processes obtained from the designed machine tool are presented to illustrate achievable high specific removal rates. Specific grinding energies are shown alongside with measured contact arc temperatures. An enhanced single-pole thermocouple technique was used to measure the actual contact temperatures in deep cutting. The performance of conventional wheels is depicted together with the performance of a CBN wheel obtained from actual industrial tests.

Blade Loadings for Hovercraft and other Radial Flow Fans

1967 ◽  
Vol 9 (4) ◽  
pp. 265-277 ◽  
Author(s):  
A. D. S. Carter
Keyword(s):  
Radial Flow ◽  
Axial Flow ◽  
Maximum Temperature ◽  
Centrifugal Fan ◽  
Blade Loading ◽  
Guide Vanes ◽  
Inlet Guide Vanes ◽  
Flow Compressor ◽  
High Work ◽  
Outside Diameter

The layout of a hovercraft leads naturally to the choice of a radial outward flow fan, but the aerodynamic requirements are more stringent than those normally associated with industrial fans. In this paper a blade loading criterion used extensively in axial flow compressor practice has been adapted to the more general case of radial flow fans. Using this criterion maximum fluid deflections and maximum temperature rise coefficients have been calculated. It is shown that fluid deflections in radial fans should be substantially lower than those in axial flow machines. For high work output the ratio of rotor outside diameter to rotor inside diameter should be as close to unity as is mechanically possible. Inlet guide vanes would be of no benefit to the conventional industrial type centrifugal fan, but for such applications as hovercraft inlet guide vanes could be most beneficial. The paper outlines those areas in which further research is necessary fully to confirm the approach, and hence the quantitative values, given in this paper.

The Aerodynamics of Trailing-Edge-Cooled Transonic Turbine Blades: Part 2 — Theoretical and Computational Approach

1997 ◽  
Author(s):  
Mathias Deckers ◽  
John D. Denton
Keyword(s):  
Transonic Flow ◽  
Theoretical Study ◽  
Computational Study ◽  
Control Volume ◽  
Turbine Blades ◽  
Computational Approach ◽  
Trailing Edge ◽  
Time Marching ◽  
Transonic Turbine ◽  
Volume Method

A theoretical and computational study into the aerodynamics of trailing-edge-cooled transonic turbine blades is described in this part of the paper. The theoretical study shows that, for unstaggered blades with coolant ejection, the base pressure and overall loss can be determined exactly by a simple control volume analysis. This theory suggests that a thick, cooled trailing edge with a wide slot can be more efficient than a thin, solid trailing edge. An existing time-marching finite volume method is adapted to calculate the transonic flow with trailing edge coolant ejection on a structured, quasi-orthogonal mesh. Good overall agreement between the present method, inviscid and viscous, and experimental evidence is obtained.

The Stress Problem of Vibrating Compressor Blades

1955 ◽  
Vol 22 (1) ◽  
pp. 57-64
Author(s):  
Jan R. Schnittger
Keyword(s):  
Turbine Blades ◽  
General Nature ◽  
Compressor Blades ◽  
Stress Problem ◽  
Simplified Analysis ◽  
Compressor And Turbine Blades

Abstract In order to demonstrate the general nature of the actual vibrations of compressor and turbine blades, the author undertakes a simplified analysis in which a single stiff blade, with one translational and one pitching mode, is studied. It is shown that all problems of stress in vibrating compressor blades whether they arise from forced or self-sustained vibrations may be related to the magnitude of finite mechanical or aerodynamic disturbances.

Investigation of the Effect of Cutting Conditions and Tool Edge Radius on Micromachining with the Use of the Finite Elements Method

2015 ◽  
Vol 2 (1) ◽  
pp. 26-37
Author(s):  
Angelos P. Markopoulos ◽  
Christos Hadjicostas ◽  
Dimitrios E. Manolakos
Keyword(s):  
Size Effect ◽  
High Efficiency ◽  
Cutting Conditions ◽  
Tool Geometry ◽  
Manufacturing Processes ◽  
Third Wave ◽  
Fem Model ◽  
Tool Edge ◽  
Aisi 1045 ◽  
Made In

Micromachining comprises manufacturing processes that are in the forefront of contemporary industry. The need for high efficiency, high precision, better quality and lower cost makes the study of these processes and the phenomena of the micro regime that accompany, e.g. the size effect, of great importance. The quite popular for modeling manufacturing processes Finite Element Method is applicable in micromachining, too. However, assumptions and simplifications need to be made in order to provide a realistic simulation. In the present paper a numerical simulation using the Third Wave AdvantEdge® software is presented. A FEM model of micromachining of AISI 1045 is used for a parametric analysis of the simulation of micro-cutting. The effect of cutting conditions and tool geometry are investigated and size-effect theories are tested with the aid of the numerical model. From the analysis several useful conclusions are drawn.

Modal Testing for Validation of Blade Models

2008 ◽  
Vol 32 (2) ◽  
pp. 91-102 ◽  
Author(s):  
D. Todd Griffith ◽  
Thomas G. Carne ◽  
Joshua A. Paquette
Keyword(s):  
Model Validation ◽  
Turbine Blades ◽  
Structural Models ◽  
Modal Testing ◽  
Wind Turbine Blades ◽  
Test Technique ◽  
Modal Test ◽  
Test Result ◽  
Made In

The focus of this paper is a test program designed for wind turbine blades. Model validation is a comprehensive undertaking which requires carefully designing and executing experiments, proposing appropriate physics-based models, and applying correlation techniques to improve these models based on the test data. Structural models are useful for making decisions when designing a new blade or assessing blade performance, and the process of model validation is needed to ensure the quality of these models. Blade modal testing is essential for validation of blade structural models, and this report discusses modal test techniques required to achieve validation. Choices made in the design of a modal test can significantly affect the final test result. This study aims to demonstrate the importance of the proper pre-test design and test technique for validating blade structural models.

Assessment of Nonresearch Industry Payments to Otolaryngologists in 2014 and 2015

2018 ◽  
Vol 158 (6) ◽  
pp. 1028-1034 ◽  
Author(s):  
Neil Pathak ◽  
Rance J. T. Fujiwara ◽  
Saral Mehra
Keyword(s):  
Annual Variation ◽  
Public Awareness ◽  
Large Change ◽  
Cross Sectional ◽  
Food And Beverage ◽  
Long Term Trends ◽  
The Mean ◽  
Open Payments ◽  
Made In

Objective To characterize, describe, and compare nonresearch industry payments made to otolaryngologists in 2014 and 2015. Additionally, to describe industry payment variation within otolaryngology and among other surgical specialties. Study Design Retrospective cross-sectional database analysis. Setting Open Payments Database. Subjects and Methods Nonresearch payments made to US otolaryngologists were characterized and compared by payment amount, nature of payment, sponsor, and census region between 2014 and 2015. Payments in otolaryngology were compared with those in other surgical specialties. Results From 2014 to 2015, there was an increase in the number of compensated otolaryngologists (7903 vs 7946) and in the mean payment per compensated otolaryngologist ($1096 vs $1242), as well as a decrease in the median payment per compensated otolaryngologist ($169 vs $165, P = .274). Approximately 90% of total payments made in both years were attributed to food and beverage. Northeast census region otolaryngologists received the highest median payment in 2014 and 2015. Compared with other surgical specialists, otolaryngologists received the lowest mean payment in 2014 and 2015 and the second-lowest and lowest median payment in 2014 and 2015, respectively. Conclusion The increase in the mean payment and number of compensated otolaryngologists can be explained by normal annual variation, stronger industry-otolaryngologist relationships, or improved reporting; additional years of data and improved public awareness of the Sunshine Act will facilitate determining long-term trends. The large change in disparity between the mean and median from 2014 to 2015 suggests greater payment variation. Otolaryngologists continue to demonstrate limited industry ties when compared with other surgical specialists.

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