Abstract    This research has been carried out to determine the marine propeller hydro-acoustic characteristics by Reynolds-Averaged Navier-Stokes (RANS) solver in both uniform and non-uniform wake flow at different operating conditions Wake flow can cause changes in pressure fluctuation and gas effect on propeller noise spectrum. Noise is generated by the induced trailing vortex wake and induced pressure pulses. The two-step Fflowcs Williams and Hawkings (FW-H) equations are used to calculate hydrodynamic pressure and its performance as well as sound pressure level (SPL) at various points around the propeller. The directivity patterns of this propeller and accurate explanation of component propeller noise are discussed. Comparison of the numerical results shows good agreement with the experimental data. Based on these results, effects of wake flow and operating conditions on the noise reduction are investigated.

Keywords    Marine propeller, Sound pressure Level, Hydrodynamic performance

چکیده    پژوهش انجام شده در این مقاله خصوصیات نویز هیدرودینامیکی پروانه های دریایی به روش رینولدز متوسط ناویر استوکس RANS در جریان یکنواخت و غیریکنواخت و در شرایط عملکردی مختلف بررسی شده است. و یک جریان می­تواند روی نوسانات میدان فشار اطراف پروانه تاثیر بگذارد. در مقاله های مختلف تاثیر این پارامتر روی نویز کمتر بررسی شده است. نویز در این حالت از القا ورتکس لبه فرار و پالس های فشاری ایجاد می­شود. از معادلات دو مرحله ای ویلیامز ها وکینگز FW-H برای محاسبه نوسانات فشاری و سطح نویز استفاده شده است. میدان جریان اطراف پروانه و پارامترهای مختلف موثر در نویز پروانه به تفصیل در این مقاله بررسی شده است. برای اعتبار سنجی نتایج هیدرودینامیکی و هیدرو اکوستیکی از نتایج تجربی استفاده شده که تطابق خوبی مشاهده می­شود. بر اساس نتایج حاصل از این مقاله، تاثیرات ویک ورودی و تاثیرات نسبت سرعت پیشروی بر روی سطح نویز پروانه های دریایی بدست آمده است.

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