مطالعهٔ تجربی برای به‌دست‌آوردن ضریب رسانایی حرارتی بتن

نوع مقاله : مقاله پژوهشی

نویسندگان

عماد پروازه ¹

هادی فرزان ¹

مهران امیری ²

محمد شفیعی ¹

¹ گروه مهندسی مکانیک، دانشکده فنی، دانشگاه ولی عصر رفسنجان، رفسنجان، ایران.

² گروه مهندسی مکانیک، دانشگاه شهید باهنر کرمان، کرمان، ایران.

10.22067/jacsm.2026.96507.1384

چکیده

کارایی حرارتی بتن نقش بسیار مهمی در طراحی ساختمان‌های کم‌مصرف دارد، به‌ویژه در سازه‌هایی که از سامانه‌های فتوولتائیک–حرارتی یکپارچه (PIPVT) استفاده می‌کنند؛ جایی‌که انتقال حرارت بهینه برای بازیابی مؤثر انرژی حرارتی و کنترل دمای پنل‌های خورشیدی ضروری است. نوآوری این پژوهش در بهبود و اندازه‌گیری تجربی رسانایی حرارتی بتن با استفاده از براده‌های آهن به‌عنوان افزودنی رسانا است، به‌طوری‌که نتایج با یک دستگاه اندازه‌گیری اختصاصی طراحی‌شده، صحه‌گذاری شده‌اند.
به دلیل محدودیت دستگاه‌های رایج در اندازه‌گیری دقیق خواص حرارتی بتن، یک سامانه آزمایشی ویژه طراحی و کالیبره شد. ابتدا رسانایی حرارتی بتن معمولی تعیین گردید، سپس نمونه‌هایی با حدود ۲ درصد وزنی و ۵.۵ درصد وزنی براده آهن، ۵ درصد کنسانتره بتن و مقدار کمی الیاف کتان ساخته و بررسی شدند. نتایج نشان داد که رسانایی حرارتی به ترتیب ۵۳٪، ۶۵٪ و ۳۰٪ افزایش یافته است، در حالی که الیاف کتان باعث کاهش جزئی حدود ۲٪ شد. مقایسهٔ پیش‌بینی‌های نظری با اندازه‌گیری‌های تجربی تطابقی حدود ۸۵٪ را نشان داد که قابلیت اعتماد دستگاه طراحی‌شده را تأیید می‌کند.
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کلیدواژه‌ها

بتن

رسانایی حرارتی

براده‌های آهن

موضوعات

• انتقال حرارت

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عنوان مقاله English

Experimental study to obtain the thermal conductivity coefficient of concrete

نویسندگان English

emad parvazeh ¹

Hadi Farzan ¹

Mehran Ameri ²

Mohammad shafiey ¹

¹ Department of Mechanical Engineering, Faculty of Engineering, Vali-e- Asr University of Rafsanjan, Rafsanjan, Iran.

² Department of Mechanical Engineering, Shahid Bahonar University of Kerman, Kerman, Iran.

چکیده English

The thermal performance of concrete plays a critical role in energy-efficient building design, particularly in structures integrating photovoltaic-integrated photovoltaic-thermal (PIPVT) systems, where enhanced heat transfer is essential for effective thermal energy recovery and photovoltaic temperature regulation. The novelty of this study lies in the experimental enhancement and quantification of concrete's thermal conductivity using iron shavings as a conductive additive, with results validated through a custom-designed measurement apparatus. Due to the limitations of conventional devices in accurately measuring the thermal properties of concrete, a dedicated experimental setup was developed and calibrated. The thermal conductivity of plain concrete was first determined, followed by mixtures incorporating approximately 2 weight percent(wt%) and 5.5wt% iron shavings,5%concrete concentrate, and a small amount of hemp fiber. The results showed increases in thermal conductivity of 53%,65%, and 30%, respectively, while the hemp fiber caused a slight reduction of 2%. A comparison between theoretical predictions and experimental measurements demonstrated approximately 85%agreement, confirming the reliability of the developed apparatus.

کلیدواژه‌ها English

concrete

thermal conductivity

iron filings

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