Improvements in Performance Characteristics of Single-Stage and Multistage Centrifugal Compressors by Simultaneous Adjustments of Inlet Guide Vanes and Diffuser Vanes

1987 ◽  
Vol 109 (1) ◽  
pp. 41-47 ◽  
Author(s):  
H. Simon ◽  
T. Wallmann ◽  
T. Mo¨nk
Keyword(s):  
Performance Characteristic ◽  
Guide Vane ◽  
Three Dimensional ◽  
Maximum Efficiency ◽  
Inlet Guide Vane ◽  
Centrifugal Compressors ◽  
Guide Vanes ◽  
Inlet Guide Vanes ◽  
The Individual ◽  
Simultaneous Adjustment

Nowadays, multistage geared centrifugal compressors are most often equipped with three-dimensional impellers and adjustable inlet guide vane cascades, at least upstream of the first stage. Optimum stage efficiencies are made possible by optimum axial in-flow into each stage and freely selectable pinion shaft speeds. Combined with intercooling of the medium, the result is high machine efficiency with good operating ranges. Additional increases in efficiency can be achieved by means of vaned diffusers. Due to the attendant restriction to the working range, this solution is not common in production compressors. Nevertheless, the working range can be distinctly expanded by adjusting the diffuser vanes. In addition, the combination of simultaneous adjustment to inlet guide vanes and diffuser vanes enables an increase in machine efficiency over the entire operating range as compared with regulation using only inlet guide vanes or diffuser vanes. This paper reports on the development of centrifugal compressor stages equipped with vaned diffusers. The impellers have backward-curved blades. Experimental determination of suitable schedules for simultaneous adjustment of both inlet guide vanes and diffuser vanes, depending on the desired performance characteristic, will be dealt with in detail. Furthermore, some examples of the overall performance maps for multistage inter-cooled geared compressors will be shown as a result of combining the performance characteristic curves of the individual stages. The operating ranges and regions of maximum efficiency are optimally matched to the requirements in question by means of suitable adjustment schedules.

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.

The Effects of Variable-Inlet Guide Vanes on Performance of an Axial Flow Pump With Tip Clearance

2015 ◽  
Author(s):  
Wei-Min Feng ◽  
Jing-Ye Pan ◽  
Zhi-Wei Guo ◽  
Qian Cheng
Keyword(s):  
Reverse Flow ◽  
Guide Vane ◽  
Axial Flow ◽  
Tip Clearance ◽  
Inlet Guide Vane ◽  
Guide Vanes ◽  
Inlet Guide Vanes ◽  
Pump Head ◽  
Axial Flow Pump ◽  
Flow Pump

The effects of variable-inlet guide vanes on the performance of an axial flow pump considering tip clearance are investigated. The performance and the main flow field of the whole passage with five different angles of inlet guide vanes ( −10°, −5°, 0°, 5°, 10°) and with two tip clearance sizes (1‰ and 2‰) are presented. The results show that when the angle of inlet guide vane increases from negative values to positive values, the pump head reduces for two tip clearance sizes. This is mainly caused by the change of inlet velocity triangle of blade. Moreover, as tip clearance size increases from 1‰ to 2‰, both the pump head and efficiency decrease because of increasing of the strength of tip clearance leakage vortex and reverse flow.

Inlet Guide Vane Performance of Centrifugal Blowers

1961 ◽  
Vol 83 (4) ◽  
pp. 371-378
Author(s):  
A. J. Stepanoff
Keyword(s):  
Centrifugal Pump ◽  
Guide Vane ◽  
Power Reduction ◽  
Single Stage ◽  
Experimental Results ◽  
Inlet Guide Vane ◽  
Pump Field ◽  
Guide Vanes ◽  
Inlet Guide Vanes ◽  
Specific Speed

The function and effectiveness of the inlet guide vanes to control the blower output and power requirements are examined. Calculated and experimental results of the power reduction by means of guide vanes are presented. The concept of the “Inlet Specific Speed” widely used in centrifugal pump field is discussed in application to the blowers. A method of estimating the performance of single-stage blowers for any position of the guide vanes is suggested. A “casing characteristic” is introduced for this purpose and its utility for the calculation of the impeller diameter for a reduction of the output is demonstrated. The performance of the inlet vanes of multistage blowers is reviewed.

Experimental and numerical analysis of the unsteady influence of the inlet guide vanes on cavitation performance of an axial pump

2018 ◽  
Vol 233 (11) ◽  
pp. 3816-3826 ◽  
Author(s):  
Zhiwei Guo ◽  
Jingye Pan ◽  
Zhongdong Qian ◽  
Bin Ji
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Computational Fluid Dynamics ◽  
Guide Vane ◽  
Inlet Guide Vane ◽  
Guide Vanes ◽  
Inlet Guide Vanes ◽  
Cavitation Performance ◽  
Axial Pump ◽  
Simulation Results

The effect of the inlet guide vanes on cavitation performance of an axial pump is investigated to assess the mechanism for cavitation in pumps and improve their cavitation performance. The effect of inlet guide vane angles on cavitation performance was assessed experimentally, and computational fluid dynamics was used to analyze the inner flow field of the axial pump and to probe the cavitation mechanism. The simulation results agree qualitatively with the experimental data, showing that cavitation performance is improved with positive inlet guide vane angles but hampered with negative ones. The cavitation performance itself is controlled by the cavitation volume, which first expands circumferentially when the net positive suction head decreases from a certain large value and then develops toward the axis radially after the net positive suction head reaches a certain value. This is when the cavitation performance deteriorates. Comparing cavitation volume for the critical net positive suction head as determined by two different methods, the method based on efficiency drop (NPSHeff.,1%) is found to be more suitable than that based on head drop (NPSHhead.,3%). Furthermore, the distribution of swirl is shown to be closely related to the distribution of cavitation, a feature that may be used to predict cavitation along the impeller.

Experimental Investigation of Forced Response Impeller Blade Vibration in a Centrifugal Compressor With Variable Inlet Guide Vanes: Part 1—Blade Damping

2011 ◽  
Author(s):  
Armin Zemp ◽  
Reza S. Abhari ◽  
Beat Ribi
Keyword(s):  
Centrifugal Compressor ◽  
Guide Vane ◽  
Operating Conditions ◽  
Inlet Pressure ◽  
Dynamic Strain ◽  
Inlet Guide Vane ◽  
Guide Vanes ◽  
Aerodynamic Damping ◽  
Inlet Guide Vanes ◽  
Vane Angle

Forming the first part of a two-part paper, the quantification of the resonant response levels and the damping quantities for a centrifugal compressor impeller with variable inlet guide vanes under engine representative operating conditions is detailed in this work. The motivation for the investigation is the lack of experimental data that are needed to improve and validate computational tools used during the design phase. Measurements were performed during resonant blade vibrations with the inlet pressure, the inlet guide vane angle and the operating point as the varying parameters. The flow non-uniformity introduced into the inlet flow field was measured with an aerodynamic probe. These measurements showed an increase in flow distortion for increased guide vane angles. The response amplitudes were acquired with dynamic strain gauges. A curve-fit method was applied to estimate the critical damping ratios. The results showed a linear correlation of the aerodynamic damping with the inlet pressure. The mode dependent material damping was therefore derived using a linear extrapolation to vacuum conditions of the inlet pressure dependent overall damping. The resonant blade dynamics could be captured with a single degree of freedom model. The aerodynamic damping and the maximum strain response were found to significantly depend on the inlet guide vane angle setting and on the throttle setting of the compressor.

Design of a Free Turbine for Simulation of Flow in a Turbine-Annular-Diffuser-With-Struts Delivery System

2009 ◽  
Author(s):  
Srinuvasu Dakuri ◽  
Bhaskar Roy
Keyword(s):  
Guide Vane ◽  
Air Flow ◽  
Inlet Guide Vane ◽  
Design Intent ◽  
Flow Angle ◽  
Guide Vanes ◽  
Inlet Guide Vanes ◽  
Annular Diffuser ◽  
The Absolute ◽  
Turbine Design

A free turbine is intended to produce the effect of a rotating flow field to be fed into a strutted annular diffuser for simulating a 3D fluid mechanic interaction and effect. This turbine is driven by the flow from a flow driver fan, upstream of the turbine. As sufficient pressure is required for the diffuser air flow, the concept of maximum work generation by a turbine is bypassed in the design intent. An inlet guide vane is designed for the turbine such that the rotational speed of the turbine matches the design intended speed and also produces an axial exit flow (no swirl) at design condition, and a rotating wake for off design conditions. The consideration of using of the inlet guide vanes (rather than usual stator-nozzles) is to avoid a mismatch between the absolute angle of the flow coming from the flow driver fan and the absolute design intent flow angle requirement, to run the turbine. Also, due to the 3D flow effects, some uncertainty exists in determining the exact entry air flow angle to the guide vane; this uncertainty is provided for with a rounded leading edge to the inlet guide vanes. The above design considerations when embedded in the conventional turbine design procedure resulted in an unusual turbine design with very low blade cambers.

scholarly journals Aerodynamic design schemes of the inlet guide vane in a core-driven fan stage

2018 ◽  
Vol 10 (1) ◽  
pp. 168781401774770
Author(s):  
Hui Cao ◽  
Zhenggui Zhou ◽  
Jinhuan Zhang
Keyword(s):  
Guide Vane ◽  
Large Angle ◽  
Simulation Method ◽  
Low Flow ◽  
Inlet Guide Vane ◽  
Geometrical Parameters ◽  
Guide Vanes ◽  
Flow Losses ◽  
Inlet Guide Vanes ◽  
Rear Part

A core-driven fan stage operates in both single bypass and double bypass modes. There are large differences in aerodynamic parameters between the two modes. To accommodate the differences, the inlet guide vanes must turn in a very large angle, which may cause significant flow losses. To reduce the flow losses, this article investigates three design schemes in detail using the flow field simulation method. The three schemes investigated include the inlet guide vanes adjusting entirely (Scheme 1), the rear part of the inlet guide vanes adjusting (Scheme 2), and both the front and rear part of the inlet guide vanes adjusting (Scheme 3). Comparisons of the three design schemes suggest that the flow losses in Scheme 1 are higher than those in the other two schemes and that the flow losses in Scheme 3 are not evidently lower than those in Scheme 2. The key geometrical parameters of Schemes 1 and 2 are determined for low flow losses and are used to design the inlet guide vanes. The inlet guide vanes are applied to a core-driven fan stage, and the flow fields are simulated by a three-dimensional flow simulation method to confirm the designs.

Influence of Freely Rotating Inlet Guide Vanes on the Return Flows and Stable Operating Range of an Axial Flow Fan

1980 ◽  
Vol 102 (1) ◽  
pp. 75-80 ◽  
Author(s):  
N. Venkatrayulu ◽  
D. Prithvi Raj ◽  
R. G. Narayanamurthi
Keyword(s):  
Guide Vane ◽  
Axial Flow ◽  
Inlet Guide Vane ◽  
Axial Distance ◽  
Axial Flow Fan ◽  
Guide Vanes ◽  
Operating Range ◽  
Inlet Guide Vanes ◽  
Stable Operating ◽  
Return Flows

This paper presents the results of experimental investigations on the three-dimensional flow and performance characteristics of a free vortex axial flow fan rotor, with a freely rotating and braked inlet guide vane row. The influences of axial distance between the inlet guide vane row and the rotor inlet, inlet guide vane setting angle and shape, partial omission of guide vanes at the hub and tip regions on the return flows have been studied and optimum axial distance and setting angle that will improve the useful operating range of the fan were determined. Use of freely rotating inlet guide vanes at high flow volumes and braked inlet guide vanes at low flow coefficients resulted in a reduction of return flows and an increase of the stable operating range of the axial fan rotor by more than 35 percent and this combination has yielded higher efficiencies as well in the extended region of stable operation.

Numerical Study of the Flow in the Flow Path of a Centrifugal Natural Gas Compressor at Different Positions of the Inlet Guide Vane

2021 ◽  
pp. 94-108
Author(s):  
M.V. Krutikov ◽  
V.L. Blinov
Keyword(s):  
Natural Gas ◽  
Gas Flow ◽  
Numerical Study ◽  
Guide Vane ◽  
Flow Path ◽  
Inlet Guide Vane ◽  
Guide Vanes ◽  
Operating Modes ◽  
Inlet Guide Vanes ◽  
Wide Range

The paper focuses on the problem of a possible expansion of the range of operating modes of a centrifugal natural gas compressor due to the rotation of the inlet guide vanes at different rotor speeds. The geometry of the flow path of the investigated object, obtained by three-dimensional scanning, is presented. On its basis, a numerical model is built and the influence of various factors of the formulation of the computational problem on the results of modeling the gas flow in the flow path of the compressor is analyzed. The calculations were performed using the k--ε and SST turbulence models for various parameters of the computational grid and conditions for averaging the flow parameters between the computational domains. The results obtained were compared with the nameplate and operational data. Recommendations on the formulation of the modeling problem are proposed, the results of the calculations are described, and the characteristics of the centrifugal compressor are plotted at different angles of the inlet guide vanes in a wide range of rotor speeds. The possible range of expansion of the operating modes of the investigated compressor is described, which can be provided by varying the position of the inlet guide vane

Unsteady Flow Around Suction Elbow and Inlet Guide Vanes in a Centrifugal Compressor

2004 ◽  
Author(s):  
Michael M. Cui
Keyword(s):  
Flow Field ◽  
Unsteady Flow ◽  
Centrifugal Compressor ◽  
Guide Vane ◽  
Power Laws ◽  
Working Fluid ◽  
Inlet Guide Vane ◽  
Guide Vanes ◽  
Inlet Guide Vanes ◽  
Compressor Design

A suction elbow and inlet guide vanes (IGVs) are typical upstream components in the front of the first-stage impeller in a centrifugal compressor. Since the flow field in the front of the impeller is subsonic, the flow motion induced by the rotating impeller interacts with the elbow and IGVs. These interactions induce turbulent unsteady flows inside compressors. The resulted unsteadiness affects efficiency, vibration, and noise generation of the compressor. To understand the mechanism controlling the interactions between up-steam components and to optimize the compressor design for better efficiency and reliability, the turbulent unsteady flow inside the first-stage of the compressor was simulated. The model includes the suction elbow, inlet guide vane housing, and first-stage impeller. HFC 134a was used as the working fluid. The thermodynamic and transport properties of the refrigerant gas were modeled by the Martin-Hou equation of state and power laws, respectively. The three-dimensional unsteady flow field was numerically simulated. The overall performance parameters were obtained by integrating the field quantities. The force, torque, and the arm of moments acting on the IGVs are then calculated. The results can be used to improve centrifugal compressor design to achieve higher efficiency and improve reliability.

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