Numerical Investigation of High Bypass Ratio Fan Tone Noise

Abstract

Results of the high bypass ratio (>8) turbojet fan tone noise simulations in the cutback and sideline operating conditions are presented. Calculations are performed using the method of 3D unsteady numerical calculation of interaction between fan rows implemented in the 3DAS (3 Dimensional Acoustics Solver) CIAM in-house solver. The results of computations are compared with the experimental data for the fan under consideration, obtained in the anechoic chamber of CIAM C-3A acoustic test facility. Comparison was performed for first three harmonics of tone noise for each of conditions. It showed satisfactory qualitative and quantitative agreement between the results of the simulation and the experiment.

Frequency-domain method for multistage turbomachine tone noise calculation

“…The other types of boundary conditions, and the numerical schemes, used for the nonlinear frequency domain calculations are common for all methods of calculations, implemented in 3DAS solver, and their description can be found in literature. 16,17,19 The principles of mode selection…”

“…3DAS solver admits calculations either in the time domain [16][17][18] or in the frequency domain for the specified set of harmonics. 8,9,19 The calculation in the frequency domain can be performed using either linear 8,9 or nonlinear inviscid equations for disturbances. 19 The method for nonlinear calculations in the frequency domain is based on the harmonic balance approach.…”

“…8,9,19 The calculation in the frequency domain can be performed using either linear 8,9 or nonlinear inviscid equations for disturbances. 19 The method for nonlinear calculations in the frequency domain is based on the harmonic balance approach. 10,11 Following McMullen et al, 11 the data are stored in the frequency domain as a set of fields of harmonics.…”

“…The solver was used for calculation of tone noise of open rotors, 16,18 low pressure compressors, 9 turbines, 17 and of different types of fans. 17,19 The method is verified on two numerical problems. One is the tone noise generation by a 2D two stage turbine.…”

Использование Осесимметричного Метода Гармонического Баланса Для Расчета Распространения Нестационарных Возмущений По Тракту Авиационного Двигателя

“…Программный комплекс был разработан для расчета тонального шума, генерируемого турбомашинами в ближнем и дальнем акустическом поле. Он использовался для расчета тонального шума различных типов вентиляторов [4,9], турбин [4], открытых роторов [5] и компрессоров низкого давления [10].…”