Journal of Aerospace Science and Technology

Journal of Aerospace Science and Technology

A Study on Lean, Sweep and Chord Length Effects on Aerodynamic Performance of Axial Fan of a High-bypass ratio Turbofan Engine

Document Type : Original Article

Authors
Amin Sarabchi
Mojtaba Heydarian Shahri
Ali Madadi
Amirkabir University of Technology, Department of Aerospace Engineering
10.22034/jast.2021.287695.1068
Abstract
Compared to the enormous costs of laboratory experiments, numerical approaches to improving the performance of turbomachines are less costly and more practical. In the present study, by using the Taguchi method and orthogonal arrays while doing a limited number of simulations (according to the Taguchi method), the sensitivity level of objective functions have been investigated to optimization variables in a fan of a high-bypass ratio turbofan engine (JT9D-7 Engine). a mathematical parameterized algorithm coupled to a computational fluid dynamic solution  is employed to modify the geometry and calculate the objective functions. 15 optimization variables are defined by varying:

The radial distribution of the chord length from the hub to the tip of the blade and also
each profile's lean and sweep in five control points compared to hub profile.

The lean, sweep and chord length are parameterized by a spline algorithm. The objective functions included the pressure ratio, isentropic efficiency and mass flow rate of the fan in the design point. The results showed that the lean angle affects the isentropic efficiency, and the sweep angle affects the mass flow rate of the fan. The pressure ratio was sensitive to both variables. Concerning the design variables, 2-level L16 and L32 arrays of the Taguchi method were used for running the sensitivity analysis. Assuming a fixed number of blades, a fixed angle of incidence, and a fixed camber angle, distributing the chord length did not significantly affect the objective functions compared to the lean and sweep distribution.
Keywords
the Taguchi method
fan
lean
sweep
chord

Subjects

[1] Wilson, Alec, et al. "Multidisciplinary Optimization of a Transonic Fan for Low Tone Noise." 17th AIAA/CEAS Aeroacoustics Conference (32nd AIAA Aeroacoustics Conference). 2011.
[2] J. Denton و L. Xu ", THE EFFECTS OF LEAN AND SWEEP ON TRANSONIC FAN PERFORMANCE," ASME TURBO EXPO,2002.
[3] E. Benini ", Three-Dimensional Multi-Objective Design Optimization of a Transonic Compressor Rotor," JOURNAL OF PROPULSION AND POWER,2004.
[4] A. Oyama و M.-S. Liou ", Transonic Axial-Flow Blade Optimization: Evolutionary Algorithms/Three-Dimensional Navier–Stokes Solver," JOURNAL OF PROPULSION AND POWER, 2004.
[5] C.-M. JANG, P. LI و K.-Y. KIM ", Optimization of Blade Sweep in a Transonic Axial Compressor Rotor," JSME International Journal,2005.
[6] A. Samad و K.-Y. Kim ", Multi-objective optimization of an axial compressor blade," Journal of Mechanical Science and Technology 22, 2008.
[7] S. R. Razavi و M. Boroomand ", Numerical and Performance Analysis of one row Transonic Rotor with Sweep and Lean angle," Journal of Thermal Science, 2014.
[8] Siller, U. and Aulich, M., 2010, October. Multidisciplinary 3d-optimization of a fan stage performance map with consideration of the static and dynamic rotor mechanics. In Turbo Expo: Power for Land, Sea, and Air (Vol. 44021, pp. 317-328).
[9] Siller, U., Voß, C. and Nicke, E., 2009, January. Automated multidisciplinary optimization of a transonic axial compressor. In 47th AIAA Aerospace Sciences Meeting Including The New Horizons Forum and Aerospace Exposition (p. 863).
[10] M. Neshat, M. Akhlaghi, A. Fathi و H. Khaledi, "Investigation the effect of the blade sweep and lean in one stage of an industrial gas turbine's transonic compressor," Propulsion andPowerResearc, 2015.
[11] Deng, X., Guo, F., Liu, Y. and Han, P., 2013. Aeromechanical optimization design of a transonic fan blade. In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers Digital Collection.
[12] Chahine, C., 2018. Multidisciplinary design optimization of aero-engine fan blades (Doctoral dissertation, University of Oxford).
[13] Gaffin, W.O., 1980. Engine component improvement: Performance improvement, JT9D-7 3.8 AR fan.
[14] ANSYS ",ANSYS TurboSystem User's Guide",2013.
[15] ANSYS Inc ",.ANSYS CFX-Solver Theory Guide",2009.
[16] Strazisar, Anthony J., et al. Laser anemometer measurements in a transonic axial-flow fan rotor. Lewis Research Center, 1989.
[17] Roy, Ranjit K. A primer on the Taguchi method. Society of Manufacturing Engineers, 2010.
Journal of Aerospace Science and Technology
Volume 14, Issue 1
April 2021
Pages 45-55

  • Receive Date 24 May 2021
  • Revise Date 23 August 2021
  • Accept Date 06 October 2021
  • First Publish Date 06 October 2021