مدل‌سازی دینامیک سیال در یک خشک‌کن جریان متقاطع شلتوک با دو ورودی بهینه هوای کنارگذر و میان‌گذر

نوع مقاله : مقاله پژوهشی

نویسندگان

1 بخش تحقیقات فنی و مهندسی کشاورزی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی فارس، سازمان تحقیقات، آموزش و ترویج کشاورزی، شیراز، ایران

2 دانش‌آموخته کارشناسی ارشد، دانشکده مهندسی، دانشگاه آزاد اسلامی، واحد بافق، بافق، ایران

3 موسسه تحقیقات فنی و مهندسی کشاورزی، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران

چکیده

در خشک‌کن رایج شلتوک (خشک‌کن‌های بستر خوابیده)، خشک شدن به صورت یکنواخت صورت نمی‌گیرد. برای رفع این مشکل، دو الگوی جریان هوای کنارگذر شامل کانال ورود هوا به توده شلتوک از جانب و میان‌گذر شامل ورود هوا به میان توده شلتوک تعریف و نحوه توزیع جریان در توده متخلخل شلتوک توسط نرم‌افزار فلوئنت در شرایط گذرا شبیه‌سازی شده است. در الگوی کنارگذر، هوا از دیواره‌های جانبی مخزن و در میان گذر، از کانال وسط مخزن وارد می‌شود. در مدل‌سازی، دمای هوای 40 درجه سلسیوس با جریان 550 مترمکعب در ساعت درنظر گرفته شد. شبیه‌سازی نشان داد، هوا در الگوی میان‌گذر با سرعت بیشتری جریان می‌یابد و به تمام نقاط مخزن شلتوک نفوذ می‌کند. عدم وجود کانال میانی در الگوی کنارگذر منجر به تولید میدان دمایی نامنظم با اعوجاج زیاد می‌شود. راست‌آزمایی داده‌های دما نشان داد که دمای اندازه‌گیری شده با دمای حاصل از شبیه‌سازی عددی 2 درصد اختلاف دارد.  

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Computational Fluid Dynamics Analysis in a Corn Air Flow Paddy Dryer with Two Types of Passing Air Flow of Lateral and Central Pattern

نویسندگان [English]

  • Omid Reza Roustapour 1
  • Omid Azimi 2
  • Hamid Reza Gazor 3
1 Department of Agricultural Engineering Research, Fars Research and Education Center for Agriculture and Natural Resources, Agricultural Research, Education and Extension Organization (AREEO), Shiraz, P.O. Box:71555-617, Iran
2 Graduated Student, Engineering College, Bafgh Branch, Islamic Azad University, Bafgh, Iran
3 Agricultural Engineering Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
چکیده [English]

Drying process is not uniform in the common rice dryers (batch type dryers). In order to decrease this problem, two types of passing hot air dryer consisted of the lateral and central patterns has been defined and method of air distribution in the rice porous media modeled by Fluent software in transient condition. In the lateral pattern, air enters through the side walls of the dryer chamber and in the central pattern, air enters through the central channel of the dryer chamber. The air temperature is 40 oc and air flow rate is 550 m3/h in all models. The results of simulation illustrate, the air flows more rapidly in the central pattern and penetrates into all parts of the dryer chamber. There is not any central passing air channel in the lateral pattern so, it caused to produce an irregular temperature field with high distortion. Models were verified in steady state condition. Results show the final temperature of model was near the measured data with 2% deviation.

کلیدواژه‌ها [English]

  • Paddy dryer
  • Numerical simulation
  • Porous media
  • Lateral pattern
  • Central pattern
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