Measurement of Instantaneous Pressure and Velocity in Nonsteady Three-Dimensional Water Flow by Means of a Combined Five-Hole Probe

1980 ◽  
Vol 102 (2) ◽  
pp. 196-202 ◽  
Author(s):  
S. Matsunaga ◽  
H. Ishibashi ◽  
M. Nishi
Keyword(s):  
Water Flow ◽  
High Frequency ◽  
Flow Measurement ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Inviscid Flow ◽  
Nonsteady Flow ◽  
High Frequency Response ◽  
Iterative Correction ◽  
Instantaneous Pressure

A new combined five-hole probe with hemispherical head of 2.0 mm diameter is developed for the measurement of nonsteady three-dimensional water flow. Each pressure hole is connected to a small semiconductor pressure transducer, which has a high frequency response, and the instantaneous pressure can be measured continuously by the probe. In the case of nonsteady flow, pressures detected by the probe are affected by the inertia due to flow unsteadiness. Therefore, in order to achieve an accurate nonsteady flow measurement, it is vital to reduce the inertial effects from the pressure reading. In the present study the inviscid flow analysis was carried out to evaluate the error due to the inertial effect, and the iterative correction procedure was examined by computer simulation.

Optimization of the Three-Dimensional Flow Path in the Scroll-Nozzle System of a Radial Inflow Turbine

1984 ◽  
Vol 106 (2) ◽  
pp. 511-515 ◽  
Author(s):  
E. A. Baskharone
Keyword(s):  
Flow Analysis ◽  
Three Dimensional ◽  
Inviscid Flow ◽  
Three Dimensional Flow ◽  
Multiply Connected ◽  
Dimensional Flow ◽  
Nozzle Configuration ◽  
Flow Domain ◽  
Radial Inflow Turbine ◽  
Compressibility Effects

A three-dimensional inviscid flow analysis in the combined scroll-nozzle system of a radial inflow turbine is presented. The coupling of the two turbine components leads to a geometrically complicated, multiply-connected flow domain. Nevertheless, this coupling accounts for the mutual effects of both elements on the three-dimensional flow pattern throughout the entire system. Compressibility effects are treated for an accurate prediction of the nozzle performance. Different geometrical configurations of both the scroll passage and the nozzle region are investigated for optimum performance. The results corresponding to a sample scroll-nozzle configuration are verified by experimental measurements.

Three-dimensional inviscid flow analysis of turbofan forced mixers

1985 ◽  
Author(s):  
T. BARBER ◽  
G. MULLER ◽  
S. RAMSAY ◽  
E. MURMAN
Keyword(s):  
Flow Analysis ◽  
Three Dimensional ◽  
Inviscid Flow

scholarly journals Numerical Simulation of Cascade Flow: Vortex Element Method for Inviscid Flow Analysis and Axial Turbine Blade Design

2021 ◽  
Vol 85 (2) ◽  
pp. 14-23
Author(s):  
Nono Suprayetno ◽  
Priyono Sutikno ◽  
Nathanael P. Tandian ◽  
Firman Hartono
Keyword(s):  
Best Practice ◽  
Lift Coefficient ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Inviscid Flow ◽  
Turbine Rotor ◽  
Design Stage ◽  
Outer Diameter ◽  
Axial Turbine ◽  
Cascade Flow

This study aims to design an axial turbine rotor blade and predict the turbine performance at preliminary design stage. Quasi three dimensional method was applied to design including blade to blade flow analysis. The blade profile uses a NACA 0015 airfoil by varying the profile thickness from hub to tip. The profile is divided into eleven segments which has different parameters. The profile was analysed using blade to blade flow/cascade flow analysis called vortex panel method to obtain lift coefficient. The analysis of cascade flow was performed in potential flow and prediction of turbine perfomance is carried out involving common best practice to give drag effect on the blade. The design of the turbine was applied on three different rotors, which also have a different discharge, head, and design rotation. The outer diameter of turbine 1 is 0.65 m, while turbine 2 and turbine 3 have an outer diameter of 0,60 m. The calculation result show that the efficiency of turbines 1, 2, and 3 were 88,32%, 89,67%, and 89,04%, respectively.

scholarly journals A Rapid Aerodynamic Loading Procedure for Centrifugal Impeller Design

1994 ◽  
Author(s):  
J. H. G. Howard ◽  
Colin Osborne ◽  
David Japikse
Keyword(s):  
Industrial Design ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Design Procedure ◽  
Inviscid Flow ◽  
Centrifugal Impeller ◽  
Zone Model ◽  
Geometry Design ◽  
Loading Method ◽  
Rapid Loading

A crucial aspect of the design process for centrifugal impellers is the establishment of specific blade shapes. A rapid inviscid flow analysis procedure was developed for incorporation within a geometry manipulation code. Using a single streamtube model, a single-pass computation technique was generated. A two-zone model ensures that key features of the passage flow physics are incorporated. Several examples of industrial design problems are employed to demonstrate the capabilities of the rapid loading method and its use in a geometry design procedure (used by some 20 industrial design groups worldwide). Comparisons with a quasi-three-dimensional method are included. The rapid loading method is most accurate when the meridional stream paths have similar shapes to those for the hub and shroud contours. The technique is useful within a geometry generation program since rapid aerodynamic screening of candidate configurations is allowed with sufficient accuracy to avoid the need for quasi-three-dimensional approaches. If required, the final design may be analyzed using three-dimensional viscous flow calculation methods.

scholarly journals Flow Field in the Turbine Rotor Passage in an Automotive Torque Converter Based on the High Frequency Response Rotating Five-hole Probe Measurement Part II: Flow field at the off-design condition and effects of speed ratio

2001 ◽  
Vol 7 (4) ◽  
pp. 271-284 ◽  
Author(s):  
Y. F. Liu ◽  
B. Lakshminarayana ◽  
J. Burningham
Keyword(s):  
Pressure Drop ◽  
Flow Field ◽  
High Frequency ◽  
Flow Measurement ◽  
Torque Converter ◽  
Turbine Rotor ◽  
Speed Ratio ◽  
High Frequency Response ◽  
Measurement Results ◽  
Overall Performance

The flow field at the design condition was presented and interpreted in Part I. The flow field at one off-design condition (Speed Ratio 0.065) is presented and interpreted in this part. In addition, the hydraulic performance is analyzed by using flow measurement results both upstream and downstream of the turbine and inside the turbine rotor passage. It is found that at the off-design conditions, especially the near stall condition (Speed Ratio 0.065), most of the pressure drop occurs in the first half of turbine passage. About 82% of the total torque is extracted between the turbine inlet and the middle plane. In addition, the shell develops torque at nearly five times the rate of core. Furthermore, the higher the speed ratio, the higher the total pressure drop. Loss is maximum at the near stall condition and varies almost linearly with the speed ratios. A compromise has to be made between the design and the off-design performance in order to improve the overall performance and fuel economy of torque converters.

scholarly journals Time Resolved Measurements in a Low Aspect Ratio Transonic Compressor Stage

1982 ◽  
Author(s):  
A. H. Epstein ◽  
W. T. Thompkins ◽  
J. L. Kerrebrock ◽  
W. F. Ng
Keyword(s):  
Aspect Ratio ◽  
High Frequency ◽  
Three Dimensional ◽  
Compressor Stage ◽  
Test Rig ◽  
Time Resolved ◽  
Transonic Compressor ◽  
High Frequency Response ◽  
Low Aspect Ratio ◽  
Conventional Test

The time resolved flowfield in a low aspect ratio transonic compressor stage has been studied using a high frequency response sphere probe with a bandpass of D.C. to 20 kHz in a blowdown compressor facility. Averaged over the compressor annulus, the data agree well with those measured with standard pilot type probes on the same stage in a conventional test rig. Not all the spanwise distributions agree, however. These differences are explained as errors in the pilot probe readings due to fluctuations in the flow. The experimental data are compared to the results of a three-dimensional inviscid Euler calculation.

Three-dimensional flow measurement of a water flow in a sphere-packed pipe by digital holographic PTV

2015 ◽  
Vol 98-99 ◽  
pp. 1864-1867 ◽  
Author(s):  
Shin-ichi Satake ◽  
Yusuke Aoyagi ◽  
Noriyuki Unno ◽  
Kazuhisa Yuki ◽  
Yohji Seki ◽  
...  
Keyword(s):  
Water Flow ◽  
Flow Measurement ◽  
Three Dimensional ◽  
Three Dimensional Flow ◽  
Dimensional Flow

A Novel Energy Flow Model for High-Frequency Vibration Analysis of Beams in a Thermal Environment

2013 ◽  
Author(s):  
Wenbo Zhang ◽  
Hualing Chen ◽  
Danhui Zhu ◽  
Xiangjie Kong
Keyword(s):  
High Frequency ◽  
Thermal Effects ◽  
Energy Flow ◽  
Thermal Stresses ◽  
Thermal Environment ◽  
Flow Analysis ◽  
Effect Of Temperature ◽  
Stress Effect ◽  
High Frequency Response ◽  
Acoustic Community

As an exceedingly important issue in vibro-acoustic community, the thermal effects can significantly affect the dynamic behaviors of the structures. The previous studies are mainly performed using the deterministic methods which are infeasible at high frequencies. Energy flow analysis (EFA) is a recent method for high-frequency structural analysis. However, until now the thermal effects are neglected in EFA studies. In this paper, a novel EFA model is developed to predict the high-frequency response of beams in a thermal environment. The wavenumber related with the axial membrane force arising from thermal stresses is considered in the derivation, and then the thermal stress effect is incorporated in the EFA governing equation in terms of effective damping loss factor. In addition, the effect of temperature-dependent material properties is included in the EFA formulation. The proposed EFA model is validated against the modal analysis for a simply supported beam for various frequencies and damping loss factors, and good agreements are found. The results indicate that the thermal effects can affect spatial distributions and levels of the energy density, and the vibrational response of beam increases with temperature.

Development of a Hydraulic Actuator to Superimpose Oscillation in Metal-Forming Presses

2011 ◽  
Vol 473 ◽  
pp. 217-222 ◽  
Author(s):  
Bernd Arno Behrens ◽  
Sven Hübner ◽  
Richard Krimm ◽  
Christian Wager ◽  
Milan Vucetic ◽  
...  
Keyword(s):  
Metal Forming ◽  
High Frequency ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Hydraulic Cylinder ◽  
High Frequency Oscillation ◽  
Hydraulic Actuator ◽  
Simulation Code ◽  
Actuation System ◽  
Piston Valve

A novel principle of a rotary piston valve and a high-frequency cylinder for a hydraulic actuation system are presented. This system will be utilized in metal-forming presses to superimpose a high-frequency oscillation on the movement of the ram. This technique was proven to enhance the forming parts quality, to extend the process limits and to reduce the forming force significantly. The key components of the valve are a stator and a rotary piston with radial drilled holes that is designed to provide a pulsating pressure and mass flow rate at a high frequency. A hydraulic cylinder is connected to the valve and converts the pulsating flow into a dynamic process force. The valve and the cylinder will be mounted on the bolster plate of a metal-forming press. In order to superimpose oscillation in the main forming direction, the cylinder is centered under the punch of the metal-forming tool. Three-dimensional computational fluid dynamics (CFD) simulations have been conducted to evaluate and to optimize the designs of the main components of the system. Hereby the commercial simulation code of ANSYS CFX was employed to determine the properties of the cylinder and the valve. Through its mesh motion technique, this simulation code allows the flow analysis between the rotary and the stationary part of the valve. Furthermore the dynamic characteristics of the system have been investigated under the influence of inertia and the compressibility of oil.

Investigation of the influence of the flow structure on the accuracy of flow measurement before a hydrometric structure in an open channel

2020 ◽  
pp. 41-44
Author(s):  
Anatoly Kusher
Keyword(s):  
Velocity Profile ◽  
Flow Velocity ◽  
Water Flow ◽  
Flow Measurement ◽  
Water Discharge ◽  
Critical Depth ◽  
Flow Measurements ◽  
Study Results ◽  
Flow Velocity Profile ◽  
Upstream Flow

The reliability of water flow measurement in irrigational canals depends on the measurement method and design features of the flow-measuring structure and the upstream flow velocity profile. The flow velocity profile is a function of the channel geometry and wall roughness. The article presents the study results of the influence of the upstream flow velocity profile on the discharge measurement accuracy. For this, the physical and numerical modeling of two structures was carried out: a critical depth flume and a hydrometric overfall in a rectangular channel. According to the data of numerical simulation of the critical depth flume with a uniform and parabolic (1/7) velocity profile in the upstream channel, the values of water discharge differ very little from the experimental values in the laboratory model with a similar geometry (δ < 2 %). In contrast to the critical depth flume, a change in the velocity profile only due to an increase in the height of the bottom roughness by 3 mm causes a decrease of the overfall discharge coefficient by 4…5 %. According to the results of the numerical and physical modeling, it was found that an increase of backwater by hydrometric structure reduces the influence of the upstream flow velocity profile and increases the reliability of water flow measurements.

Sign in / Sign up

Export Citation Format

Share Document