scholarly journals The Design Method of Axial Flow Runners Focusing on Axial Flow Velocity Uniformization and Its Application to an Ultra-Small Axial Flow Hydraulic Turbine

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Yasuyuki Nishi ◽  
Yutaka Kobayashi ◽  
Terumi Inagaki ◽  
Norio Kikuchi
Keyword(s):  
Flow Velocity ◽  
Performance Test ◽  
Design Method ◽  
Axial Flow ◽  
Internal Flow ◽  
Hydraulic Turbine ◽  
Small Rivers ◽  
Axial Component ◽  
Turbine Efficiency ◽  
Piv Measurement

We proposed a portable and ultra-small axial flow hydraulic turbine that can generate electric power comparatively easily using the low head of open channels such as existing pipe conduits or small rivers. In addition, we proposed a simple design method for axial flow runners in combination with the conventional one-dimensional design method and the design method of axial flow velocity uniformization, with the support of three-dimensional flow analysis. Applying our design method to the runner of an ultra-small axial flow hydraulic turbine, the performance and internal flow of the designed runner were investigated using CFD analysis and experiment (performance test and PIV measurement). As a result, the runners designed with our design method were significantly improved in turbine efficiency compared to the original runner. Specifically, in the experiment, a new design of the runner achieved a turbine efficiency of 0.768. This reason was that the axial component of absolute velocity of the new design of the runner was relatively uniform at the runner outlet in comparison with that of the original runner, and as a result, the negative rotational flow was improved. Thus, the validity of our design method has been verified.

scholarly journals Study of the internal flow structure of an ultra-small axial flow hydraulic turbine

2019 ◽  
Vol 139 ◽  
pp. 1000-1011 ◽  
Author(s):  
Yasuyuki Nishi ◽  
Tomoyuki Kobori ◽  
Nozomi Mori ◽  
Terumi Inagaki ◽  
Norio Kikuchi
Keyword(s):  
Flow Structure ◽  
Axial Flow ◽  
Internal Flow ◽  
Hydraulic Turbine

Advances in Design Methods and Characteristics of Internal Flow for Centrifugal Pumps

2010 ◽  
Author(s):  
Shouqi Yuan ◽  
Jianping Yuan ◽  
Houlin Liu ◽  
Yue Tang ◽  
Jinfeng Zhang ◽  
...  
Keyword(s):  
Unsteady Flow ◽  
Pressure Pulsation ◽  
Design Method ◽  
Internal Flow ◽  
Design Methods ◽  
Centrifugal Pumps ◽  
Flow Induced Vibration ◽  
Hydraulic Design ◽  
Piv Measurement ◽  
Engineering And Technology

Centrifugal pump is widely used in various fields of the national economy. Pumps, of which 70% are centrifugal pumps, consume 20.9% of the total electricity generation nationwide in China in 2009, according to the statistics. In this paper, the research advances in design methods and characteristics of internal flow fields for centrifugal pumps, carried out by the Research Center of Fluid Machinery Engineering and Technology of Jiangsu University, is introduced. First of all, the Greater Flow Design method, Non-Overload Design method and Splitter Blade Offset Design method are fully discussed through systematically studies. In addition, three methods of performance prediction for centrifugal pumps are adopted, and a CAD/CFD software for hydraulic design and analysis is initially developed. Secondly, to deepen the understanding of characteristics of internal flow in centrifugal pumps, the numerical simulation and PIV measurement investigation have been done. Then the unsteady flow induced vibration and noise are studied considering fluid-structure interaction and fluid-sound interaction. The control of the unsteady flow in centrifugal pumps is also attempted to optimize the design method for centrifugal pumps. In addition, the pressure pulsation and vibration behaviors under both cavitation and non-cavitation conditions are obtained and analyzed. Finally, some detecting methods and criterion for cavitation incipiency and development are put forward.

319 Study on Design Method Based on Axial Velocity Uniformity of Ultra-small Axial Flow Hydraulic Turbine

2015 ◽  
Vol 2015.23 (0) ◽  
pp. 157-158
Author(s):  
Yutaka KOBAYASHI ◽  
Yasuyuki NISHI ◽  
Terumi INAGAKI ◽  
Yanrong LI ◽  
Norio KIKUCHI
Keyword(s):  
Axial Velocity ◽  
Design Method ◽  
Axial Flow ◽  
Hydraulic Turbine

Hydraulic turbine efficiency

2001 ◽  
Vol 28 (2) ◽  
pp. 238-253 ◽  
Author(s):  
J L Gordon
Keyword(s):  
Root Mean Square ◽  
Axial Flow ◽  
Hydraulic Turbine ◽  
Relative Increase ◽  
Energy Output ◽  
Mean Square ◽  
Peak Efficiency ◽  
Impulse Turbine ◽  
Turbine Efficiency ◽  
Hydraulic Turbines

A set of empirical equations has been developed which defines the peak efficiency and shape of the efficiency curve for hydraulic turbines as a function of the commissioning date for the unit, rated head, rated flow, runner speed, and runner throat or impulse turbine jet diameter. The equations are based on an analysis of peak efficiency data from 56 Francis, 33 axial-flow, and eight impulse runners dating from 1908 to the present, with runner diameters ranging from just under 0.6 m to almost 9.5 m. The metric specific speeds (nq) ranged from 5.3 to 294. The root mean square error of the calculated peak efficiency for Francis and axial-flow runners was found to be 0.65%. The shape of the efficiency curves was derived from eight Francis, five Kaplan, three propeller, and four impulse turbines. Charts showing the relationship between calculated and actual efficiency curves for these 20 runners are provided. A good match between calculated and measured or guaranteed efficiency was obtained. The equations were also used to determine the relative increase in peak efficiency for new reaction runners installed in existing casings at 22 powerplants, with a root mean square accuracy of 1.0%. The equations can be used to (i) develop efficiency curves for new and old runners; (ii) compare the energy output of alternative types of turbines, where this choice is available; and (iii) calculate the approximate incremental energy benefit from installing a new runner in an existing reaction turbine casing, or onto the shaft of an impulse unit.Key words: hydraulic turbines, turbine renovation, turbine efficiency.

0524 The Flow Field of an Axial Flow Hydraulic Turbine with a Collection Device Based on PIV Measurement and Numerical Analysis

2015 ◽  
Vol 2015 (0) ◽  
pp. _0524-1_-_0524-4_
Author(s):  
Genki SATO ◽  
Yasuyuki NISHI ◽  
Terumi INAGAKI ◽  
Yanrong LI ◽  
Sou HIRAMA ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
Flow Field ◽  
Axial Flow ◽  
Hydraulic Turbine ◽  
Collection Device ◽  
Piv Measurement

Flow through axial-flow-turbomachinery blading

2018 ◽  
Author(s):  
Marcel Escudier
Keyword(s):  
Flow Velocity ◽  
Compressible Flow ◽  
Dimensional Analysis ◽  
Incompressible Flow ◽  
Compressible Fluid ◽  
Axial Flow ◽  
Linear Cascade ◽  
Dimensional Parameters ◽  
Flow Through

This chapter is concerned primarily with the flow of a compressible fluid through stationary and moving blading, for the most part using the analysis introduced in Chapter 11. The principles of dimensional analysis are applied to determine the appropriate non-dimensional parameters to characterise the performance of a turbomachine. The analysis of incompressible flow through a linear cascade of aerofoil-like blades is followed by the analysis of compressible flow. Velocity triangles for flow relative to blades, and Euler’s turbomachinery equation, are introduced to analyse flow through a rotor. The concepts introduced are applied to the analysis of an axial-turbomachine stage comprising a stator and a rotor, which applies to either a compressor or a turbine.

Paper 10: Pressure Losses in the Inlet and Outlet Casings of Axial Flow Turbines for Turbo-Chargers

1967 ◽  
Vol 182 (4) ◽  
pp. 71-79 ◽  
Author(s):  
C. W. Simpson ◽  
D. E. Y. Scarlett
Keyword(s):  
Axial Flow ◽  
Annular Nozzle ◽  
Design Studies ◽  
Pressure Losses ◽  
Pressure Loss Coefficient ◽  
Turbine Efficiency ◽  
Annular Section ◽  
Turbine Casing ◽  
Transition Piece ◽  
Experimental Pressure

During initial design studies for a new range of turbo-chargers it was apparent that a considerable gain of efficiency could be achieved by a reduction of turbine casing losses. In this paper the theoretical and experimental pressure losses obtained from rig tests on the inlet and outlet casings for old and new designs will be presented. The inlet casing tests were completed on an axial entry casing with transition from circular to semi-annular section. The effect of this transition piece on gas incidences is also shown for the semi-annular nozzle entry. Studies on the outlet casing as a transition from annular through radial to axial flow have been completed and will be presented as a pressure loss coefficient for various designs. The tests have been undertaken with both convex and flat plate radial diffusers, with or without swirl. Different outlet ducts were used to determine the effects on pressure losses in the casings, and the results are discussed. Finally, the gains in overall turbine efficiency obtained by adopting the beneficial results from these tests are considered.

Inverse Design of Axial-Flow Compressor Blades Using Elastic Surface Algorithm in Subsonic and Transonic Flow Regimes With Separation

2016 ◽  
Author(s):  
M. H. Noorsalehi ◽  
M. Nili-Ahamadabadi ◽  
E. Shirani ◽  
M. Safari
Keyword(s):  
Pressure Distribution ◽  
Transonic Flow ◽  
Design Method ◽  
Axial Flow ◽  
Flow Regimes ◽  
Inverse Design ◽  
Elastic Surface ◽  
Axial Flow Compressor ◽  
Inverse Design Method ◽  
Flow Compressor

In this study, a new inverse design method called Elastic Surface Algorithm (ESA) is developed and enhanced for axial-flow compressor blade design in subsonic and transonic flow regimes with separation. ESA is a physically based iterative inverse design method that uses a 2D flow analysis code to estimate the pressure distribution on the solid structure, i.e. airfoil, and a 2D solid beam finite element code to calculate the deflections due to the difference between the calculated and target pressure distributions. In order to enhance the ESA, the wall shear stress distribution, besides pressure distribution, is applied to deflect the shape of the airfoil. The enhanced method is validated through the inverse design of the rotor blade of the first stage of an axial-flow compressor in transonic viscous flow regime. In addition, some design examples are presented to prove the effectiveness and robustness of the method. The results of this study show that the enhanced Elastic Surface Algorithm is an effective inverse design method in flow regimes with separation and normal shock.

Improvement of Stalling Characteristics of an Axial-Flow Fan by Radial-Vaned Air-Separators

2010 ◽  
Vol 132 (2) ◽  
Author(s):  
Nobuyuki Yamaguchi ◽  
Masayuki Ogata ◽  
Yohei Kato
Keyword(s):  
Solid Wall ◽  
Axial Flow ◽  
Internal Flow ◽  
Rotor Blades ◽  
Relative Location ◽  
Flow Conditions ◽  
Axial Flow Fan ◽  
Light Load ◽  
Stall Prevention ◽  
Air Separator

An improved construction of air-separator device, which has radial-vanes embedded within its inlet circumferential opening with their leading-edges facing the moving tips of the fan rotor-blades so as to scoop the tip flow, was investigated with respect to the stall-prevention effect on a low-speed, single-stage, lightly loaded, axial-flow fan. Stall-prevention effects by the separator layout, relative location of the separator to the rotor-blades, and widths of the openings of the air-separator inlet and exit were parametrically surveyed. As far as the particular fan is concerned, the device together with the best relative location has proved to be able to eliminate effectively the stall zone having existed in the original solid-wall characteristics, which has confirmed the promising potential of the device. Guidelines were obtained from the data for optimizing relative locations of the device to the rotor-blades, maximizing the stall-prevention effect of the device, and minimizing the axial size of the device for a required stall-prevention effect, at least for the particular fan and possibly for fans of similar light-load fans. The data suggest the changing internal flow conditions affected by the device conditions.

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