Three Dimensional Simulation of Flow in an Axial Low Pressure Compressor at Engine Icing Operating Points

Abstract Strong transient engine load steps can result in low pressure ratio (ΠC) compressor operation for single stage turbocharged (TC) systems. For conventional full load TC engine matching using one-dimensional (1D)-engine process simulation, these operating points are of limited relevance and are consequently less studied. However, for the layout of sequential turbocharging systems, low pressure ratio compressor operation has to be thoroughly understood. Therefore, in this paper, three-dimensional (3D)-computational fluid dynamics (CFD) simulations will be presented, which analyze the stationary compressor behavior at low pressure ratios. Operating points at ΠC<1 are investigated by reducing the compressor outlet pressure. The simulation results are validated against measurement data acquired at a stationary hot gas test bench. The compressor performance is quantified by a corrected compressor torque. Opposed to the well-known operation at ΠC>1, the compressor generates power close to zero speed for ΠC<1 (turbine operation). At higher mass flowrates and ΠC<1, the compressor consumes power. Pressure build-up in the wheel is overcompensated by losses in the diffusor and the volute resulting in a net pressure drop across the stage. The 3D-CFD simulations also allow a speed-dependent evaluation of the choking cross section inside the compressor. At low circumferential speeds, compressor choke occurs in the volute or at the wheel outlet. At higher speeds, choking is observed at the wheel inlet. This behavior must be accounted for compressor map extrapolation methods for 1D-engine process simulations in order to correctly predict the choking mass flowrate.

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Three-dimensional simulation of the conformality of copper layers deposited by low-pressure chemical vapor deposition from CuI(tmvs)(hfac)

Microelectronic Engineering ◽

10.1016/s0167-9317(99)00318-4 ◽

2000 ◽

Vol 50 (1-4) ◽

pp. 481-486 ◽

Cited By ~ 3

Author(s):

E Bär ◽

J Lorenz ◽

H Ryssel

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Three Dimensional ◽

Chemical Vapor ◽

Low Pressure ◽

Pressure Chemical ◽

Dimensional Simulation

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Application of Composite Materials in an Upgraded Engine Low-Pressure Compressor for a Regional Passenger Aircraft

Inventions ◽

10.3390/inventions6030054 ◽

2021 ◽

Vol 6 (3) ◽

pp. 54

Author(s):

Yury Ravikovich ◽

Alexander Arkhipov ◽

Alexander Shakhov ◽

Timur Erofeev

Keyword(s):

Composite Materials ◽

Experimental Studies ◽

Three Dimensional ◽

Dynamic Strength ◽

Low Pressure ◽

Final Decision ◽

Structural Elements ◽

Safety Margins ◽

Three Dimensional Finite Element ◽

Pressure Compressor

Computational and experimental studies have been carried out to evaluate the robustness and durability of components produced of polymer composite materials (PCM), as a part of the modernization of the low-pressure compressor (LPC) of the engine for the regional aircraft. For a preliminary assessment of the static and dynamic strength of the parts, a series of three-dimensional finite element calculations and tests of laboratory specimens, structural elements cut from finished parts, have been performed. Testing the laboratory samples made it possible to compare the obtained mechanical properties with the properties declared by PCM suppliers and to conduct a mor e correct assessment of the safety margins of the parts. To decide whether to install parts on the engine, fatigue and erosion tests of the structural elements cut from the finished parts were carried out. The final decision on the performance of the PCM parts was made after testing them as part of the upgraded LPC on the engine. The criterion for evaluating the erosion resistance of PCM parts has been introduced, which makes it possible to assess their performance during operation.

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Application of Multistage CFD Analysis to Low Pressure Compressor Design

Volume 5: Turbo Expo 2004, Parts A and B ◽

10.1115/gt2004-54263 ◽

2004 ◽

Cited By ~ 2

Author(s):

Lisa Brilliant ◽

Stanley Balamucki ◽

George Burger ◽

Yuan Dong ◽

Charlie Lejambre

Keyword(s):

Three Dimensional ◽

Development Program ◽

Low Pressure ◽

Cfd Analysis ◽

Stall Margin ◽

Surge Margin ◽

Flow Features ◽

Stage Matching ◽

Engine Development ◽

Pressure Compressor

A Low Pressure Compressor (LPC) is unique in its requirements for wide operating range during a flight mission. As a result, the aerodynamic design involves a trade-off between performance and stall margin. The requirement to reduce engine development cost and schedule has resulted in developing LPCs during the engine validation program. With engine validation and certification schedules being compressed continuously, getting the initial design right has become critical. Multistage CFD analysis is used in the current design process to optimize the airfoils and stage matching. Three-dimensional airfoil features, such as bow, that improve secondary flow features and can be optimized using CFD. The PW6000 LPC engine test data has validated the analytical results and demonstrated surge margin and efficiency levels above the requirements. The LPC also achieved all other design objectives in its first build, representing a significant cost saving for a new centerline engine development program.

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The PROMPT project and its application to the three-dimensional simulation of low-pressure chemical vapor deposition processes

Solid-State Electronics ◽

10.1016/s0038-1101(97)00003-8 ◽

1997 ◽

Vol 41 (7) ◽

pp. 939-943

Author(s):

E Bär ◽

J Lorenz

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Three Dimensional ◽

Chemical Vapor ◽

Low Pressure ◽

Pressure Chemical ◽

Deposition Processes ◽

Dimensional Simulation

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Aerodynamic Optimization of a Two-Part Variable Inlet Guide Vane in a Highly Loaded Low Pressure Compressor

Volume 2A: Turbomachinery ◽

10.1115/gt2018-75489 ◽

2018 ◽

Author(s):

Stefan Hemmert-Pottmann ◽

William Gouézou ◽

Eberhard Nicke

Keyword(s):

Design Optimization ◽

Total Pressure ◽

Guide Vane ◽

Low Pressure ◽

Operating Conditions ◽

Inlet Guide Vane ◽

Wide Range ◽

Variable Inlet Guide Vane ◽

Operating Points ◽

Pressure Compressor

Continuous reduction of fuel consumption for a wide range of operating conditions leads to a high efficiency demand for all engine parts of modern jet engines and especially the compressor. To meet these requirements a two-part Variable Inlet Guide Vane (VIGV), composed of a fixed strut and a variable flap, can be used. Besides the aerodynamic aspects, the VIGV strut is a substantial part for the structural integrity of the compressor. The aerodynamic design optimization of such a VIGV, located upstream of the first rotor of a 2.5 stage low pressure compressor, under the conditions of three different operating points is presented in this paper. In a previous study the shape of the axial gap between strut and flap was optimized without changing the envelope of both parts [1]. The new design tool SplitBlade, developed at the DLR, enables the creation of an axial gap and has been integrated in the design process of the in-house optimization tool AutoOpti. The target of the optimization was to decrease the total pressure loss coefficients for all three operating points. The design optimization presented in this paper is more complex by allowing the VIGV blade geometry to change. The basic dimensions of the VIGV such as the axial chord and the maximum profile thickness are still frozen. In total, 88 parameters are free to change in the optimization process. Additionally to the main target of loss reduction, the circumferential outflow angles are restricted to maintain the deflection of the blade and therewith the required rotor inflow conditions to ensure the operability of the entire compressor in the whole working range. The final result is a two-part VIGV with an axial gap, which is optimized in terms of total pressure losses in three operating points. Compared to a reference geometry without an axial gap, the losses are almost equal at nominal speed, and about one to two percentage points higher in the two part speed operating points.

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