THREE-DIMENSIONAL FLOW IN A TRANSONIC AXIAL FLOW FAN OF A HIGH BYPASS RATIO TURBOFAN ENGINE

In this paper, a three-color dual-beam PDA (Particle Dynamic Analyzer) system (made by DANTEC Measurement Technology) is used to measure the three-dimensional velocity of an axial flow fan. Due to the geometrical limit of fan rotor, non-orthogonal velocity components are measured first, from which the orthogonal three-dimensional components of the velocity field are computed through transformation equations. The detailed flow fields at 15 axial locations upstream, inside and at the exit of the rotor are measured, respectively. On each cross section perpendicular to the rotating axis, the flow field measurement at 15 different radial locations from 50% of the blade span to the region inside the tip clearance (between the tip blade and the casing wall) are taken. The experimental technique is described, and the three dimensional flow fields (including the tip clearance flow) are presented and analyzed.

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A Three-Dimensional Analysis of Rotor Wakes

Aeronautical Quarterly ◽

10.1017/s0001925900006181 ◽

1972 ◽

Vol 23 (4) ◽

pp. 285-300 ◽

Cited By ~ 7

Author(s):

C E Whitfield ◽

J C Kelly ◽

B Barry

Keyword(s):

Dimensional Analysis ◽

Constant Temperature ◽

Three Dimensional ◽

Axial Flow ◽

Visual Presentation ◽

Hot Wire ◽

Three Dimensional Flow ◽

Dimensional Flow

SummaryMany investigators have studied the aerodynamics of axial flow turbomachinery but none has produced a complete map of the three-dimensional flow behind a rotor row. This is of considerable interest to the aero-acoustician. A system is described which uses a constant temperature hot-wire anemometer to analyse the flow behind such a rotor. Although much information may be extracted by using the technique, its interpretation depends to a large extent on its form of presentation. An analysis of the flow behind a research fan is used as a means of discussing various forms of visual presentation.

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Three-Dimensional Flow and Mixing in an Axial Flow Compressor With Different Rotor Tip Clearances

Journal of Turbomachinery ◽

10.1115/1.2929192 ◽

1992 ◽

Vol 114 (3) ◽

pp. 675-685 ◽

Cited By ~ 35

Author(s):

A. Goto

Keyword(s):

Velocity Fluctuation ◽

Three Dimensional ◽

Axial Flow ◽

Flow Fields ◽

Tip Clearance ◽

Small Scale ◽

Three Dimensional Flow ◽

Axial Flow Compressor ◽

Dimensional Flow ◽

Flow Compressor

The effect of difference in rotor tip clearance on the mean flow fields and unsteadiness and mixing across a stator blade row were investigated using hot-wire anemometry, pressure probes, flow visualization, and the ethylene tracer-gas technique on a single-stage axial flow compressor. The structure of the three-dimensional flow fields was discussed based on results of experiments using the 12-orientation single slanted hotwire technique and spectrum analysis of velocity fluctuation. High-pass filtered measurements of turbulence were also carried out in order to confirm small-scale velocity fluctuation, which is more realistically referred to as turbulence. The span-wise distribution of ethylene gas spreading, estimated by the measured small-scale velocity fluctuation at the rotor exit, agreed quite well with that which was experimentally measured. This fact suggests the significant role of turbulence, generated within the rotor, in the mixing process across the downstream stator. The value of the maximum mixing coefficient in the tip region was found to increase linearly as the tip clearance became enlarged, starting from the value at midspan.

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Investigation of the Three-Dimensional Flow Field Within a Transonic Fan Rotor: Experiment and Analysis

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.3239744 ◽

1985 ◽

Vol 107 (2) ◽

pp. 436-448 ◽

Cited By ~ 18

Author(s):

M. J. Pierzga ◽

J. R. Wood

Keyword(s):

Aspect Ratio ◽

Flow Field ◽

Numerical Technique ◽

Pressure Ratio ◽

Three Dimensional ◽

Axial Flow ◽

Data Matrix ◽

Three Dimensional Flow ◽

Dimensional Flow ◽

Finite Volume Approach

An experimental investigation of the three-dimensional flow field through a low aspect ratio, transonic, axial-flow fan rotor has been conducted using an advanced laser anemometer (LA) system. Laser velocimeter measurements of the rotor flow field at the design operating speed and over a range of through flow conditions are compared to analytical solutions. The numerical technique used herein yields the solution to the full, three-dimensional, unsteady Euler equations using an explicit time-marching, finite volume approach. The numerical analysis, when coupled with a simplified boundary layer calculation, generally yields good agreement with the experimental data. The test rotor has an aspect ratio of 1.56, a design total pressure ratio of 1.629 and a tip relative Mach number of 1.38. The high spatial resolution of the LA data matrix (9 radial × 30 axial × 50 blade-to-blade) permits details of the transonic flow field such as shock location, turning distribution, and blade loading levels to be investigated an compared to analytical results.

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