ارزیابی تأثیر الگوی وزشی سیستم تهویه انفرادی بر احساس گرمایی موضعی بدن

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشیار، گروه مهندسی مکانیک، دانشگاه بیرجند، بیرجند، ایران

2 دانشجوی کارشناسی ارشد، گروه مهندسی مکانیک، دانشگاه بیرجند، بیرجند، ایران

3 دانشجوی دکتری، گروه مهندسی مکانیک، دانشگاه بیرجند، بیرجند، ایران

چکیده

تحقیق حاضر باهدف تحلیل تاثیر جانمایی دریچه ورود هوا و مشخصه‌های جریان بر عملکرد یک سیستم تهویه انفرادی صورت پذیرفته‌‌است. به‌این منظور یک اتاق اداری مجهز به سیستم تهویه‌انفرادی باحضور آدمک گرمایی، به‌صورت عددی شبیه‌سازی شده‌‌است. برای دریچه ورود هوا سه جانمایی مختلف (مقابل پا، مقابل شکم و مقابل صورت) و برای هر جانمایی دو دمای هوای ورودی (16 و 20 درجه سلسیوس) و دو سرعت وزش (1 و 2 متر بر ثانیه) درنظر گرفته‌شده‌است. در نهایت، توزیع دما، توزیع سرعت ‌هوا و احساس گرمایی کلی و موضعی بخش­های مختلف بدن تعیین شده‌است. در برخی حالت‌ها با تغییر جانمایی دریچه از مقابل پا به‌مقابل شکم و سر، احساس کلی بدن به‌ترتیب تا 54/0 و 6/0 واحد خنک‌تر شده‌است. در تمام حالت‌ها دست و سر احساس خنک‌تری نسبت به احساس کل بدن داشته‌اند که نشان‌می‌دهد در سیستم تهویه انفرادی، برهنگی تاثیر قابل توجهی بر احساس عضو دارد. سر برخلاف پا، یک عضو موثر برای سرمایش غیریکنواخت در شرایط گرم بوده و به دلیل تاثیر آن بر احساس کلی بدن، سرمایش سر می‌تواند راهکاری موثر برای کاهش مصرف انرژی باشد.

کلیدواژه‌ها

موضوعات


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