مدلسازی عددی برای تحلیل پارامترهای گوناگون مبدل حرارتی زمینی به ‏منظور افزایش عملکرد هیت پمپ زمین‏ گرمایی

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه انرژی‌های نو و محیط زیست، دانشکدۀ علوم و فنون نوین، دانشگاه تهران

10.22059/ses.2023.351256.1017

چکیده

انتقال حرارت بین مبدل حرارتی زمین‌گرمایی و خاک در سیستم‌های هیت پمپ زمین‌گرمایی نقش اساسی در بازده کلی سیستم دارد. از این‌رو، در این مقاله با اضافه کردن موادی با ضریب انتقال حرارت بالا در مبدل‌های حرارتی عمودی مارپیچ، اثر آن‏ها روی بازده و دمای خروجی مبدل حرارتی بررسی شد. مقالۀ حاضر با استفاده از محیط COMSOL شبیه‏سازی عددی را برای مدل 1 بعدی-3 بعدی پمپ‏های حرارتی زمین‌گرمایی در حالت خنک‏کننده ارائه می‏کند. به خلاف مدل‌های مارپیچی رایج، این مدل با عمق کم و قطر زیاد با میله‌های فلزی مخصوص (Fins) طراحی شده است. لولۀ مارپیچ شبیه‌سازی‌شده دارای عمق 10 متر و قطر 1 متر است. به منظور جبران کاهش انتقال حرارت ناشی از عمق کمتر، تأثیر پارامترهای مختلف از جمله گام، هدایت حرارتی بر عملکرد حرارتی بررسی شده است . همچنین، به عنوان یک نوآوری، نوعی طرح نوآورانه متشکل از انواع متنوع میله‌های آلومینیومی افقی (Fins) در خاک متصل به لوله کاملاً (Finned pipe) مدل‌سازی شده است. پره‌ها نه تنها لوله را در داخل زمین محکم نگه می‌دارند، بلکه سرعت انتقال حرارت را به دلیل افزایش مساحت و سیستم هدایت حرارتی بالا تا 31 درصد بهبود می‌بخشند.
 
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کلیدواژه‌ها


عنوان مقاله [English]

Numerical Simulation of a Novel Spiral Type Ground Heat Exchanger for En-hancing Heat Transfer Performance of Geothermal Heat Pump

نویسندگان [English]

  • Reza Saeidi
  • Javad Aghaz
Department of Renewable Energies and Environment, Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran
چکیده [English]

The spiral type one is more prominent, of which the vertical type ground heat exchange (GHE) is the most common in ground source heat pumps (GSHP) and on the purpose of this study as well. The present paper provides numerical simulation for 1D-3D model of the ground source heat pumps in cooling mode by using COMSOL environment. In contrary to popular spiral models, this model is designed with a low depth and high diameter with special metal rods (Fins). The simulated spiral pipe has 10 m in depth and 1 m in diameter. In order to compensate for the reduction in heat transfer due to the lower depth, the effect of different parameters such as velocity, pitch, thermal conductivity, and specific heat capacity in backfill material and ground on the heat performance is investigated. Furthermore, different velocity range is recommended for several pitches. In addition, as a novelty, an innovative design is modeled consisting of diverse type of horizontal aluminum rods (Fins) in the soil connected to the pipe completely (Finned pipe). The fins not only hold the pipe inside the ground firmly but also improve the heat transfer rate due to the area increase and the high thermal conductivity system up to 31%.

کلیدواژه‌ها [English]

  • Heat Transfer
  • Vertical Ground Heat Exchanger
  • Geothermal Heat Pump
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