Influence of technological factors on porosity in the mass production of inlet guide vanes using additive technologies

Engine downsizing is a modern solution for the reduction of CO2 emissions from internal combustion engines. This technology has been gaining increasing attention from industry. In order to enable a downsized engine to operate properly at low speed conditions, it is essential to have a compressor stage with very good surge margin. The ported shroud, also known as the casing treatment, is a conventional way used in turbochargers to widen the working range. However, the ported shroud works effectively only at pressure ratios higher than 3:1. At lower pressure ratio, its advantages for surge margin enhancements are very limited. The variable inlet guide vanes are also a solution to this problem. By adjusting the setting angles of variable inlet guide vanes, it is possible to shift the compressor map toward the smaller flow rates. However, this would also undermine the stage efficiency, require extra space for installing the inlet guide vanes, and add costs. The best solution is therefore to improve the design of impeller blade itself to attain high aerodynamic performances and wide operating ranges. This paper reports a recent study of using inverse design method for the redesign of a centrifugal compressor stage used in an electric supercharger, including the impeller blade and volute. The main requirements were to substantially increase the stable operating range of the compressor in order to meet the demands of the downsized engine. The three-dimensional (3D) inverse design method was used to optimize the impeller geometry and achieve higher efficiency and stable operating range. The predicted performance map shows great advantages when compared with the existing design. To validate the computational fluid dynamics (CFD) results, this new compressor stage has also been prototyped and tested. It will be shown that the CFD predictions have very good agreement with experiments and the redesigned compressor stage has improved the pressure ratio, aerodynamic efficiency, choke, and surge margins considerably.

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Blade Loadings for Hovercraft and other Radial Flow Fans

Journal of Mechanical Engineering Science ◽

10.1243/jmes_jour_1967_009_042_02 ◽

1967 ◽

Vol 9 (4) ◽

pp. 265-277 ◽

Cited By ~ 1

Author(s):

A. D. S. Carter

Keyword(s):

Radial Flow ◽

Axial Flow ◽

Maximum Temperature ◽

Centrifugal Fan ◽

Blade Loading ◽

Guide Vanes ◽

Inlet Guide Vanes ◽

Flow Compressor ◽

High Work ◽

Outside Diameter

The layout of a hovercraft leads naturally to the choice of a radial outward flow fan, but the aerodynamic requirements are more stringent than those normally associated with industrial fans. In this paper a blade loading criterion used extensively in axial flow compressor practice has been adapted to the more general case of radial flow fans. Using this criterion maximum fluid deflections and maximum temperature rise coefficients have been calculated. It is shown that fluid deflections in radial fans should be substantially lower than those in axial flow machines. For high work output the ratio of rotor outside diameter to rotor inside diameter should be as close to unity as is mechanically possible. Inlet guide vanes would be of no benefit to the conventional industrial type centrifugal fan, but for such applications as hovercraft inlet guide vanes could be most beneficial. The paper outlines those areas in which further research is necessary fully to confirm the approach, and hence the quantitative values, given in this paper.

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Application of Aerodynamically Induced Prewhirl to a Small Turbocharger Compressor

Journal of Engineering for Power ◽

10.1115/1.3230365 ◽

1980 ◽

Vol 102 (4) ◽

pp. 943-950 ◽

Cited By ~ 15

Author(s):

N. Kyrtatos ◽

N. Watson

Keyword(s):

Mathematical Model ◽

Design Procedure ◽

Performance Data ◽

Inlet Flow ◽

Guide Vanes ◽

Inlet Guide Vanes ◽

Compressor Performance

A design procedure is described which allows the development of an arrangement to aerodynamically impart prewhirl to the inflow of a compressor. The procedure uses compressor performance data and inducer inlet flow distributions together with a mathematical model of the aerodynamic prewhirl inducing arrangement to arrive at the parameters which completely define an arrangement suitable for a particular compressor. The application of the procedure to design an arrangement for a small turbocharger compressor is presented. The effect of the aerodynamically imparted prerotation on the compressor performance was found to be similar to that produced by inlet guide vanes.

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Development of Inlet for an Axial Compressor

ASME 1968 Gas Turbine Conference and Products Show ◽

10.1115/68-gt-41 ◽

1968 ◽

Author(s):

R. C. Reisweber

Keyword(s):

Axial Compressor ◽

Axial Flow ◽

Test Program ◽

Guide Vanes ◽

Inlet Guide Vanes ◽

Compressor Inlet ◽

Three Stages ◽

Overall Performance

In development of an axial-flow boiler supercharger, a test program on the compressor inlet was carried out. Tests were run using a test compressor aerodynamically identical to the first three stages of the supercharger compressor. Prototype compressor inlet was compared to an axial inlet, and also to several modified inlets. While the prototype inlet showed considerably more distortion ahead of the inlet guide vanes than the axial inlet, the inlet guide vanes removed most of the distortion. As a result, overall performance of all inlet configurations was essentially the same.

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

Volume 2B: Turbomachinery ◽

10.1115/gt2020-14714 ◽

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.

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The Effect of Variable Inlet Guide Vanes on the Performance of Military Engine Fan

Lecture Notes in Mechanical Engineering - Design and Development of Aerospace Vehicles and Propulsion Systems ◽

10.1007/978-981-15-9601-8_28 ◽

2021 ◽

pp. 387-401

Author(s):

Baljeet Kaur ◽

Reza Abbas ◽

Ajay Pratap

Keyword(s):

Guide Vanes ◽

Inlet Guide Vanes

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Performance improvement of an axial-flow pump with inlet guide vanes in the turbine mode

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1177/0957650919858842 ◽

2019 ◽

Vol 234 (3) ◽

pp. 323-331

Author(s):

Zilong Zhao ◽

Zhiwei Guo ◽

Zhongdong Qian ◽

Qian Cheng

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

High Efficiency ◽

Design Flow ◽

Inlet Guide Vane ◽

Flow Rates ◽

Guide Vanes ◽

Inlet Guide Vanes ◽

Axial Pump ◽

Turbine Mode

The axial pump operating in the pump-as-turbine mode is a practical and cost-saving alternative suitable for low-head pico hydropower in rural and remote areas that bypasses the need for expensive turbines. Their pump characteristics, however, indicate that efficiency is low in off-design flow rates. Using the computational fluid dynamics, the adjustable inlet guide vanes with five angles (±20°, 0°, ±10°) in front of the impeller of the axial pump have been redesigned and installed specifically to increase the operating range of high efficiency in the pump-as-turbine mode. To validate the simulation method, a prototype of the axial pump was built to measure in the pump mode the pump characteristics including head and efficiency. The results obtained show that the computational fluid dynamics calculated results are in qualitative agreement with the experimental data. In the pump-as-turbine mode, the adjustable inlet guide vanes were found to affect the performance of the axial pump. The most important aspect is that the adjustable inlet guide vanes widen the efficiency range if the inlet guide vane angle is adjusted for different flow rates. For the same situation with negative angles, the efficiency values at the BEP are higher than those with positive angles, where the efficiency around the angle − 10° is the highest. The main reason is that the direction of flow at the impeller-zone exit is guided by the adjustable inlet guide vanes to reduce the energy loss, which can be supported in the view of vector field and energy losses of different parts of pump.

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