بررسی نویز اختلاط جریان های سرد و گرم در میکسر کنگره دار یک موتور توربوفن با کنارگذر بالا به روش ویلیام هاوکینگز

نوع مقاله : مقاله پژوهشی

نویسندگان

1 مجتمع دانشگاهی مکانیک- دانشگاه صنعتی مالک اشتر

2 مجتمع دانشگاهی مکانیک، دانشگاه صنعتی مالک اشتر

چکیده

امروزه، میکسرهای کنگره­دار به‌عنوان یک وسیله مؤثر کاهش صدا در موتور­های توربوفن شناخته شده‌اند. در این تحقیق، تأثیر اختلاط جریان هوای سرد و گرم در یک میکسر کنگره­دار در کاهش صدا شبیه­سازی شده است. معادلات ناویراستوکس به‌صورت سه بعدی، تراکم­پذیر، ناپایا و مغشوش درنظر گرفته شده‌اند. برای حل جریان مغشوش، از معادله اغتشاشی  استفاده ‌شده است، همچنین جهت بررسی قدرت آکوستیکی، از روش ویلیامز هاوکینگ استفاده شده است. نتایج حاصل از این تحقیق نشان می­دهد، که با دور شدن جریان خروجی از نازل موتور، میزان قدرت آکوستیکی کاهش می­یابد. همچنین، دامنه فرکانسی بین 80 تا 10000 هرتز در­نظر گرفته شده است. در فرکانس 80 هرتز، بیشترین میزان سطح فشار صوتی وجود دارد و با افزایش میزان فرکانس، میزان سطح فشار کاهش می­یابد. نتایج نشان می­دهد، میزان سطح فشار در فرکانس­های زیر 1000 هرتز نسبت به سایر محدوده فرکانسی بیشتر است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Noise Investigation of Hot and Cold Flow Mixing in a Lobed Mixer of a High Bypass Ratio Turbofan Engine by FW-H method

نویسندگان [English]

  • Milad Roumipour 1
  • Rouhollah Khoshkhoo 2
1 Faculty of Mechanical Engineering-MUT
2 Faculty of Mechanical Engineering, Malek Ashtar University of Technology
چکیده [English]

Today, lobed mixers are recognized as an effective means in reducing noise in turbofan engines. In this study, the effect of mixing hot and cold flow in a lobed mixer on noise reduction is surveyed and simulated. Navier Stokes equations are considered to be three-dimensional, compressible, unsteady, and turbulence. The k-ω SST equation has been used to solve the turbulent flow, and the Ffowcs Williams Hawkings (FW-H) model has been used to investigate the sound pressure level. The results of this study show that the amount of sound pressure level(SPL) decreases as the output current moves away from the nozzle. Also, the frequency range between 80 and 10,000 Hz is considered. At 80 Hz, there is the highest sound pressure level, and as the frequency increases, the sound pressure level decreases. The results show that the sound pressure level at frequencies below 1000 Hz is higher than other frequency ranges.

کلیدواژه‌ها [English]

  • Lobed Mixer
  • numerical simulation
  • FW-H Method
  • Acoustic
  • turbofan Engine
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