The flow field in a cross flow fan was simulated by solving the 2-D unsteady Reynolds-averaged Navier-Stokes equations. The calculated pressure fluctuations of the blades, the vortex wall, and the rear wall were then used as noise sources to calculate the sound field. The Ffowcs Williams-Hawkings (FW-H) equation was employed to predict the noise field caused by these sources. The predictions show that the rear wall and the vortex wall sources contribute significantly to the total noise and that both the predicted aerodynamic performance and noise agree well with the experimental results.
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参考文献
1. Neise W . Reviewof fan noise generations mechanisms and control methods. Proc SFA Symposium on Fan Noise, Senlis (France):CETM, 1992, 45–56
2. Moon Y J, Cho Y, Nam H-S . Computation of unsteady viscous flow and aeroacousticnoise of cross flow fans. Computers &Fluids, 2003, 32(7): 995–1015. doi:10.1016/S0045-7930(02)00068-3
3. Hu J W, Ding G L, Zhang C L . Simulation of aeroacoustic on air-conditioner. Chinese Journal of Mechanical Engineering, 2004, 40(11): 188–192 (in Chinese)
4. Cho Y, Moon Y J . Discrete noise predictionof variable pitch cross-flow fans by unsteady Navier-Stokes computations. ASME J Fluids Eng, 2003, 125(3): 543–550. doi:10.1115/1.1568356
5. Ffowcs Williams J E, Hawkings D L . Sound generation by turbulenceand surfaces in arbitrary motion. PhilosTrans R Soc London, Ser. A, 1969, 264(1151): 321–342. doi:10.1098/rsta.1969.0031
6. Toffolo A . Onthe theoretical link between design parameters and performance incross-flow fans: a numerical and experimental study. Computers & Fluids, 2005, 34(1): 49–66. doi:10.1016/j.compfluid.2004.04.002
7. Farassat F, Succi G P . The prediction of helicopterrotor discrete frequency noise. Vertica, 1983, 7(4): 309–320
8. Brentner K S . Prediction of helicopter discrete frequency rotor noise-a computerprogram incorporating realistic blade motions and advanced formulation. NASA Technical Report TM 87721. 1986
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