On the Correlation Between Spanwise Inducer Incidence and Impeller Diffusion for Ruled Surface and Barreled Sweep-Bow Impeller Design at Inlet Guide Vane-Off-Design

2021 ◽  
Vol 144 (2) ◽  
Author(s):  
A. Hildebrandt ◽  
T. Ceyrowsky ◽  
J. Klausmann ◽  
K. A. Metz
Keyword(s):  
Guide Vane ◽  
Flow Analysis ◽  
Leading Edge ◽  
High Volume ◽  
Aerodynamic Performance ◽  
Flow Coefficient ◽  
Inlet Guide Vane ◽  
Neutral Position ◽  
Design Point ◽  
One Dimensional

Abstract In the present paper, three centrifugal stages of high volume flow coefficient are compared to each-other regarding their aerodynamic performance in design point and off-design point conditions at different speed and inlet guide vane (IGV)-setting angle: two stages with full-blade design (no splitter blades) have been numerically designed with different design geometry methodology. One geometry is based on a classical ruling surface design with a linear leading edge, the second geometry based on a fully-three-dimensional surface including a blade bow at the trailing edge and a barreled sweep at the leading edge. According to impeller test rig measurements and computational fluid dynamics (CFD) calculation, the classical ruling surface designed impeller outperforms the more sophisticated centrifugal stage with fully 3D-blade at fully axially guided IGV-flow. In the contrary, at closing IGV-off-design setting angles, toward surge operation, the fully 3D-blade impeller performs with higher efficiency and steeper negative pressure slope. On the search of the geometrical causes for the different aerodynamic performance (especially at IGV-off-design conditions), focus is set on the analysis of IGV-flow-interaction with the inducer flow and impeller diffusion. The one-dimensional analysis of the spanwise flow at the impeller leading edge reveals that, compared with the ruling surface impeller, the fully 3D-blade performs with lower flow incidence losses in favor to IGV-off-design operation than at IGV-neutral position. The streamwise flow analysis confirms the improved flow incidence characteristics of the 3D-blade impeller due to reduction of aerodynamic blockage and entropy production in the vicinity of the impeller leading edge. Based on CFD calculations, a new correlation of secondary flow and flow incidence is proposed, to be used for one-dimensional modeling.

On the Correlation Between Span-Wise Inducer Incidence and Impeller Diffusion for Ruled Surface and Barreled Sweep-Bow Impeller Design at IGV-Off-Design

2021 ◽  
Author(s):  
A. Hildebrandt ◽  
T. Ceyrowsky ◽  
J. Klausmann ◽  
K. A. Metz
Keyword(s):  
Flow Analysis ◽  
Leading Edge ◽  
High Volume ◽  
Aerodynamic Performance ◽  
Flow Coefficient ◽  
Neutral Position ◽  
Design Point ◽  
One Dimensional ◽  
Centrifugal Stage ◽  
Edge Based

Abstract In the present paper, three centrifugal stages of high volume flow coefficient are compared to each-other regarding their aerodynamic performance in design point and off-design point conditions at different speed and IGV-setting angle: two stages with full-blade design (no splitter blades) have been numerically designed with different design geometry methodology. One geometry is based on a classical ruling surface design with a linear leading edge, the second geometry based on a fully-3d surface including a blade bow at the trailing edge and a barreled sweep at the leading edge. According to impeller test rig measurements and CFD-calculation, the classical ruling surface designed impeller outperforms the more sophisticated centrifugal stage with fully-3D-blade at fully axially guided IGV-flow. In the contrary, at closing IGV-off-design setting angles, towards surge operation, the fully-3D-blade-impeller performs with higher efficiency and steeper negative pressure slope. On the search of the geometrical causes for the different aerodynamic performance (especially at IGV-off-design conditions), focus is set on the analysis of IGV-flow-interaction with the inducer flow, and impeller diffusion. The one-dimensional -analysis of the span-wise flow at the impeller leading edge reveals that, compared with the ruling surface impeller, the fully 3D-blade performs with lower flow incidence losses in favor to IGV-off-design operation than at IGV-neutral position. The stream-wise flow analysis confirms the improved flow incidence characteristics of the 3D-blade impeller due to reduction of aerodynamic blockage and entropy production in the vicinity of the impeller leading edge. Based on CFD-calculations, a new correlation of secondary flow and flow incidence is proposed, to be used for one-dimensional modelling.

scholarly journals A Novel Method for Developing Compressor’s Characteristic Curves Due to the Guide Vane Stagger Angle Variation

2019 ◽  
Author(s):  
Alireza Navai ◽  
Nima Zamani Meymian
Keyword(s):  
Gas Turbines ◽  
Guide Vane ◽  
Characteristic Curve ◽  
Pressure Coefficient ◽  
Flow Coefficient ◽  
Inlet Guide Vane ◽  
Angle Variation ◽  
Characteristic Curves ◽  
One Dimensional ◽  
Stagger Angle

One-dimensional models of analyzing gas turbines as a whole require characteristic curves of pressure coefficient (ψ) based on flow coefficient (φ) and the characteristic curve of compressor’s efficiency of stages so that compressor performance would be predicted. Variation of stagger angle of the stage’s inlet guide vane stated as a geometrical variation of the stage would be resulted in the displacement of pressure coefficient characteristic curve based on the stage’s flow coefficient. Performance nature of compressor stage is in a way that under this condition, the efficiency characteristic curve will remain intact. In this paper, a method would be presented to predict variations of pressure coefficient characteristic curve based on flow coefficient against variations in stagger angle of stage’s guide vane so that one-dimensional modeling of axial flow compressor would be made, through characteristic curves.

Three-Dimensional Flow Analysis and Design Improvement of Leading-Edge Film-Cooling in an Inlet Guide Vane

2006 ◽  
Author(s):  
Bai-Tao An ◽  
Jian-Jun Liu ◽  
Hong-De Jiang
Keyword(s):  
Film Cooling ◽  
Guide Vane ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Leading Edge ◽  
Inlet Guide Vane ◽  
Original Design ◽  
Stagnation Line ◽  
Analysis And Design ◽  
Fully Implicit

Numerical investigations on the film cooling of an inlet guide vane are performed with realistic geometry. The vane model comprises one vane passage, 131 shower-head cooling holes in 6 staggered rows around the vane leading edge, and a coolant supply plenum. A fully implicit coupled 3D N-S solver based on finite-volume method and incorporated with unstructured mixed grid, standard k–ε turbulence model and scalable wall function is employed to obtain the numerical solution. Two film cooling configurations, named original design and modified design, are presented. The original design and no cooling case are simulated to obtain flow mechanism and heat transfer characteristics of the leading edge film cooling. In addition, the effects of the meridional endwall contours on the leading edge film cooling are considered. The film cooling characteristics and interactions between jets and mainstream around the leading edge, especially near the stagnation line, are analyzed in detail. To provide better coolant coverage on the leading edge, the cooling configuration is modified by redistributing the position and direction of some rows of holes based upon the analysis and understanding of the 3D prediction for the original design. The modified design is verified under three blowing ratios and compared with the original design.

Performance Prediction for Automotive Turbocharger Compressors

1975 ◽  
Vol 189 (1) ◽  
pp. 557-565 ◽  
Author(s):  
A. Whitfield ◽  
F. J. Wallace
Keyword(s):  
Performance Prediction ◽  
Flow Analysis ◽  
Compressor Stage ◽  
Thermodynamic Models ◽  
Flow Rates ◽  
Design Point ◽  
One Dimensional ◽  
Dimensional Flow ◽  
Performance Map ◽  
The Individual

A procedure to predict the complete performance map of turbocharger centrifugal compressors is presented. This is based on a one-dimensional flow analysis using existing published loss correlations that were available and thermodynamic models to describe the incidence loss and slip factor variation at flow rates which differ from the design point. To predict the losses within the complete compressor stage using a one-dimensional flow procedure, it is necessary to introduce a number of empirical parameters. The uncertainty associated with these empirical parameters is assessed by studying the effect of varying them upon the individual losses and upon the overall predicted performance.

scholarly journals Redesigning a compressor inlet guide vane for 0 to 60 degree stagger angles

2021 ◽  
Author(s):  
Stephanie Waters
Keyword(s):  
Fuel Consumption ◽  
Guide Vane ◽  
Leading Edge ◽  
Aircraft Engine ◽  
Inlet Guide Vane ◽  
Pressure Loss Coefficient ◽  
Compressor Inlet ◽  
Curvature Distribution ◽  
Stagger Angle ◽  
Total Pressure Loss Coefficient

This report's objective is to reduce the total pressure loss coefficient of an inlet guide vane (IGV) at high stagger angles and to therefore reduce the overall fuel consumption of an aircraft engine. IGVs are usually optimized for cruise where the stagger angle is approximately 0 degrees. To reduce losses, four different methodologies were tested: increasing the leading edge radius, increasing the camber, creating a "drooped nose", and creating an "S" curvature distribution. A baseline IGV was chosen and modified using these methodologies to create 10 new IGV designs. CFX was used to perform a CFD analysis on all 11 IGV designs at 5 stagger angles from 0 to 60 degrees. Typical missions were analyzed and it was discovered that the new designs decreased the fuel consumption of the engine. The IGV with the "S" curvature and thicker leading edge was the best and decreased the fuel consumption by 0.24%.

Ice Crystal Icing Investigation on a Honeywell Uncertified Research Engine in an Altitude Simulation Icing Facility

2020 ◽  
Author(s):  
Ashlie B. Flegel
Keyword(s):  
Particle Size ◽  
Guide Vane ◽  
Leading Edge ◽  
Inlet Guide Vane ◽  
Inlet Temperature ◽  
Ice Crystal ◽  
Guide Vanes ◽  
Inlet Guide Vanes ◽  
The Core ◽  
Break Up

Abstract A Honeywell Uncertified Research Engine was exposed to various ice crystal conditions in the NASA Glenn Propulsion Systems Laboratory. Simulations using NASA’s 1D Icing Risk Analysis tool were used to determine potential inlet conditions that could lead to ice crystal accretion along the inlet of the core flowpath and into the high pressure compressor. These conditions were simulated in the facility to develop baseline conditions. Parameters were then varied to move or change accretion characteristics. Data were acquired at altitudes varying from 5 kft to 45 kft, at nominal ice particle Median Volumetric Diameters from 20 μm to 100 μm, and total water contents of 1 g/m3 to 12 g/m3. Engine and flight parameters such as fan speed, Mach number, and inlet temperature were also varied. The engine was instrumented with total temperature and pressure probes. Static pressure taps were installed at the leading edge of the fan stator, front frame hub, the shroud of the inlet guide vane, and first two rotors. Metal temperatures were acquired for the inlet guide vane and vane stators 1–2. In-situ measurements of the particle size distribution were acquired three meters upstream of the engine forward fan flange and one meter downstream of the fan in the bypass in order to study particle break-up behavior. Cameras were installed in the engine to capture ice accretions at the leading edge of the fan stator, splitter lip, and inlet guide vane. Additional measurements acquired but not discussed in this paper include: high speed pressure transducers installed at the trailing edge of the first stage rotor and light extinction probes used to acquire particle concentrations at the fan exit stator plane and at the inlet to the core and bypass. The goal of this study was to understand the key parameters of accretion, acquire particle break-up data aft of the fan, and generate a unique icing dataset for model and tool development. The work described in this paper focuses on the effect of particle break-up. It was found that there was significant particle break-up downstream of the fan in the bypass, especially with larger initial particle sizes. The metal temperatures on the inlet guide vanes and stators show a temperature increase with increasing particle size. Accretion behavior observed was very similar at the fan stator and splitter lip across all test cases. However at the inlet guide vanes, the accretion decreased with increasing particle size.

scholarly journals Investigation on the Flow Field Entropy Structure of Non-Synchronous Blade Vibration in an Axial Turbocompressor

Entropy ◽  
2020 ◽  
Vol 22 (12) ◽  
pp. 1372
Author(s):  
Mingming Zhang ◽  
Anping Hou
Keyword(s):  
Flow Field ◽  
High Speed ◽  
Guide Vane ◽  
Leading Edge ◽  
Inlet Guide Vane ◽  
Tip Leakage Flow ◽  
Good Correspondence ◽  
Blade Vibration ◽  
Tip Leakage ◽  
Spiral Vortex

In order to explore the inducing factors and mechanism of the non-synchronous vibration, the flow field structure and its formation mechanism in the non-synchronous vibration state of a high speed turbocompressor are discussed in this paper, based on the fluid–structure interaction method. The predicted frequencies fBV (4.4EO), fAR (9.6EO) in the field have a good correspondence with the experimental data, which verify the reliability and accuracy of the numerical method. The results indicate that, under a deviation in the adjustment of inlet guide vane (IGV), the disturbances of pressure in the tip diffuse upstream and downstream, and maintain the corresponding relationship with the non-synchronous vibration frequency of the blade. An instability flow that developed at the tip region of 90% span emerged due to interactions among the incoming main flow, the axial separation backflow, and the tip leakage vortices. The separation vortices in the blade passage mixed up with the tip leakage flow reverse at the trailing edge of blade tip, presenting a spiral vortex structure which flows upstream to the leading edge of the adjacent blade. The disturbances of the spiral vortexes emerge to rotate at 54.5% of the rotor speed in the same rotating direction as a modal oscillation. The blade vibration in the turbocompressor is found to be related to the unsteadiness of the tip flow. The large pressure oscillation caused by the movement of the spiral vortex is regarded as the one of the main drivers for the non-synchronous vibration for the present turbocompressor, besides the deviation in the adjustment of IGV.

Periodic Transition on an Axial Compressor Stator — Incidence and Clocking Effects: Part I — Experimental Data

1998 ◽  
Author(s):  
G. J. Walker ◽  
J. D. Hughes ◽  
W. J. Solomon
Keyword(s):  
Guide Vane ◽  
Axial Compressor ◽  
Separated Flow ◽  
Leading Edge ◽  
Inlet Guide Vane ◽  
Turbulent Spot ◽  
Pressure Surface ◽  
Surface Pressure Distribution ◽  
Surface Transition ◽  
Hot Film

Periodic wake-induced transition on the outlet stator of a 1.5 stage axial compressor is examined using hot-film arrays on both the suction and pressure surfaces. The time-mean surface pressure distribution is varied by changing the blade incidence, while the freestream disturbance field is altered by clocking of the stator relative to an inlet guide vane row. Ensemble average plots of turbulent intermittency and relaxation factor (extent of calmed flow following the passage of a turbulent spot) are presented. These show the strength of periodic wake-induced transition phenomena to be significantly influenced by both incidence and clocking effects. The nature and extent of transition by other modes (natural, bypass and separated flow transition) are altered accordingly. Leading edge and mid-chord separation bubbles are affected in a characteristically different manner by changing freestream periodicity. There are noticeable differences between suction and pressure surface transition behavior, particularly as regards the strength and extent of calming. In Part II of this paper, the transition onset observations from the compressor stator are used to evaluate the quasi-steady application of conventional transition correlations to predict unsteady transition onset on the blading of an embedded axial compressor stage.

Effect of Stator Variability on Axial Compressor Performance

2019 ◽  
Author(s):  
Kirubakaran Purushothaman ◽  
N. R. Naveen Kumar ◽  
Vidyadheesh Pandurangi ◽  
Ajay Pratap
Keyword(s):  
Guide Vane ◽  
Flow Analysis ◽  
Axial Compressor ◽  
Axial Flow ◽  
Low Pressure ◽  
Inlet Guide Vane ◽  
Jet Engines ◽  
Stator Blade ◽  
And Performance ◽  
Flow Compressor

Abstract Variability in stator vanes is a widely used technique to improve the stability and efficiency of axial flow compressor in gas turbine engines. Most of the modern aircraft jet engines use variable stator vanes in both low pressure and high pressure compressors primarily for off-design performance. This study discusses in detail about the effect of stator variability in a three stage low pressure axial compressor at design and off-design conditions. Computational flow analysis were carried out for the three stage low pressure compressor with variability in inlet guide vane and first stage stator blade. Detailed investigation on flow physics was carried out in rotor blade passages with stator variability. At off-design speeds, the reduction in flow velocity is lower than the reduction in blade tip speed. This leads to mismatch in flow angles and inlet blade angles causing high incidence and large flow separation in blade passage. This results in poor aerodynamic stability of the axial compressor at off-design speeds. In this study, aerodynamic performance of compressor is evaluated from 70% to 100% design speeds with different stagger angle setting of inlet guide vane at each speed. Further, to improve 2nd stage rotor performance, variability was introduced in 1st stage stator blade and performance was evaluated. Compressor test results are compared with CFD data for design and off-design speeds.

ICE CRYSTAL ICING INVESTIGATION ON A HONEYWELL UNCERTIFIED RESEARCH ENGINE IN AN ALTITITUDE SIMULATION ICING FACILITY

2021 ◽  
pp. 1-22
Author(s):  
Ashlie Flegel
Keyword(s):  
Particle Size ◽  
Guide Vane ◽  
Model Development ◽  
Leading Edge ◽  
Inlet Guide Vane ◽  
Analysis Tool ◽  
Ice Crystal ◽  
High Pressure Compressor ◽  
Break Up ◽  
Inlet Conditions

Abstract A Honeywell Uncertified Research Engine was exposed to various ice crystal conditions in the NASA Propulsion Systems Laboratory. Simulations using NASA's 1D Icing Risk Analysis tool were used to determine potential inlet conditions that could lead to ice crystal accretion along the inlet of the core flowpath and into the high pressure compressor. Baseline conditions were established and parameters were varied to observe accretion characteristics. Data were acquired at altitudes varying from 5 kft to 45 kft, at nominal ice particle Median Volumetric Diameters from 20 µm to 100 µm, and total water contents of 1 g/m3 to 12 g/m3. Metal temperatures were acquired for the inlet guide vane and vane stators 1-2. In-situ measurements of the particle size distribution were acquired upstream and downstream of the engine fan face in order to study particle break-up behavior. Cameras were installed in the engine to capture ice accretions at the leading edge of the fan stator, splitter lip, and inlet guide vane. The goal of this study was to understand the key parameters of accretion, acquire particle break-up data aft of the fan, and generate a unique icing dataset for model development. Significant particle break-up downstream of the fan in the bypass was observed. The metal temperatures on the IGVs and stators show a temperature increase with increasing particle size. Accretion behavior at the fan stator and splitter lip across was very similar. However accretion decreased with increasing particle size at the IGVs.

Sign in / Sign up

Export Citation Format

Share Document