مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

تاثیر عامل‌های جنس ماده و بسامد صوت بر ضریب جذب و تغییرات تراز صدا

نوع مقاله : پژوهشی اصیل

نویسندگان
1 گروه مهندسی مکانیک بیوسیستم، دانشکده کشاورزی، دانشگاه شهرکرد، شهرکرد ایران
2 گروه مهندسی مکانیک بیوسیستم، دانشکده کشاورزی، دانشگاه اراک، اراک، ایران
چکیده
میزان شدت صدا در بیشتر صنایع و فرآیندها یک عامل مزاحم است. جاذب‌های صدا وسیله‌ای برای کاهش میزان سر و صدا هستند. انواع مختلفی از جاذب‌های صوتی با طراحی و جنس‌های گوناگون وجود دارد؛ اما جاذب‌های صدایی که بتوانند ضریب جذب بالایی داشته باشند، موثر واقع خواهد شد. طراحی اسفنج منگر با ساختار فرکتالی، راه‌ حل مناسبی برای این مساله خواهد بود. با توجه به اینکه عوامل مختلفی مانند جنس، گام و بسامد بر این جاذب تاثیرگذار هستند، در این پژوهش هر یک از این عامل‌ها آزمایش شدند و اثرات ضریب جذب و تغییرات تراز صدا تحت تاثیر عامل‌های جنس، گام و بسامد بررسی و تحلیل شدند. در بررسی عامل گام، مشخص شد که میزان ضریب جذب گام دوم دارای نتایج مطلوب‌تری نسبت به گام یک است. این مقدار برای گام یک ۰/۳ و برای گام دو ۰/۳۸ به­دست آمد. از میان عامل‌های موثر بر میزان ضریب جذب اسفنج منگر، عامل جنس، اثرات مشهودتری را نشان داد؛ به­نحوی که جاذب با بافت سخت‌تر دارای ضریب جذب پایین‌تر و جاذب با بافت سبک‌تر، دارای ضریب جذب بالاتر است. از میان جنس‌های به­کاررفته برای این جاذب، اسفنج دارای بالاترین ضریب جذب با مقدار۰/۴ و ام­دی­اف حداقل ضریب جذب با مقدار ۰/۳ را دارد.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Effect of Material Composition type and Audio Frequency factors on Absorption Coefficient and the Sound Level Variation

نویسندگان English

R. Mohammadi Gahrouyi 1
A. Maleki 1
M. Lashgari 2
1 Mechanical Engineering of Biosystems Department, Collage of Agriculture, Shahrekord University, Shahrekord, Iran
2 Mechanical Engineering of Biosystems Department, Collage of Agriculture, Arak University, Arak, Iran
چکیده English

The intensity of sound in most industries and processes is a disturbing factor. Sound absorbers are a means of reducing noise. There are various types of sound absorbers with different designs and materials, but sound absorbers that can have a high absorption coefficient will be effective. The design of the manger sponge with fractal structure will be a good solution to this problem. Various factors such as composition type, step, and frequency affect this adsorbent. In this research, each of these factors was investigated and analyzed. The effects of the absorption coefficient and changes in sound level influenced by composition type, step and frequency factors were investigated and analyzed. Investigation of the step factor revealed that the amount of absorption coefficient in step 2 had better results compared to the step 1. The absorption coefficient in steps 1 and 2 were 0.3 and 0.38, respectively. Among the effective factors on the amount of absorption coefficient of manger sponge, the composition type was more effective. The results showed that the adsorbent with harder texture has a lower absorption coefficient and the adsorbent with a lighter texture has a higher absorption coefficient. Among the composition type used for this adsorbent, the sponge has a maximum absorption coefficient of 0.4 and MDF has a minimum absorption coefficient of 0.3.

کلیدواژه‌ها English

Manger Sponge
Adsorbent
Acoustics
Frequency
Porosity
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