شبیه‌سازی دقیق و سریعتر از زمان واقعی جریان هوا در ساختمان با استفاده از دینامیک سیالات سریع

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد/ دانشگاه تربیت مدرس

2 تربیت مدرس * مهندسی مکانیک

چکیده

یکی از مرسومترین روشهای مدلسازی انرژی در ساختمان، روش چند ناحیه‌ای است. مشکل اساسی این روش عدم توانایی ارائه اطلاعات جزئی و دقیق از جریان هوا میباشد. برای دستیابی به اطلاعات جزئی‌تر میتوان از روش دینامیک سیالات محاسباتی استفاده نمود، اما زمان محاسبات طولانی، کاربرد این روش را محدود میسازد. بنابراین نیاز است از روشی با سرعت محاسبات بالا با توانایی ارائه جزئیات جریان هوا با دقت کافی استفاده نمود. بدین منظور در این پژوهش روش دینامیک سیالات سریع که دارای الگوریتم حل بدون قید و شرط پایدار می‌باشد ارائه شده است. برای بررسی این روش، چهار مسئله جریان درون حفره، جریان درون کانال، جریان با جابجایی طبیعی و جریان با جابجایی اجباری بررسی شده و نتایج با دادههای آزمایشگاهی، نتایج تحلیلی و نتایج دینامیک سیالات محاسباتی مقایسه و صحهگذاری شده است. تمرکز اصلی این پژوهش، افزایش سرعت حل به روش دینامیک سیالات سریع میباشد. بدین منظور زنجیره معادلات اصلاح شده و از روش عددی مناسب برای حل معادلات استفاده شده است. با بکارگیری این حلگر، زمان شبیهسازی مسائل فوق بین 52 تا 94 درصد نسبت به روش دینامیک سیالات محاسباتی کاهش یافته و شبیهسازی آنها به صورت سریعتر از زمان واقعی روی یک سیستم کامپیوتری معمولی میسر شده است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Accurate and faster than real-time simulation of indoor airflow by using fast fluid dynamics

نویسندگان [English]

  • Mirmasoud Seyedi 1
  • Hadi Pasdarshahri 2
1 MSc student, Tarbiat Modares University
2 Assistant Professor, Faculty of Mechanical Engineering, Tarbiat Modares University
چکیده [English]

The multizone model is one of the most popular models for simulating indoor energy and airflow; however, its basic problem is that it cannot provide detailed and accurate airflow information. Computational fluid dynamics can be used to obtain detailed airflow information but is restricted due to its high computational cost. Therefore, it is necessary to develop a model which can provide detailed airflow information with reasonable accuracy and computational time. In this study, fast fluid dynamics, which has an unconditionally stable algorithm, is proposed. To investigate this model, four case studies of flow in a lid-driven cavity, flow in a channel, natural and forced flow convention are analyzed, and the results are compared and validated with computational fluid dynamics, experimental data, and analytical solution. The main focus of this study is increasing the computational speed of fast fluid dynamics. For this purpose, the sequence of equations has been modified and suitable numerical methods have been applied to solve each equation. Using the proposed fast fluid dynamics solver, the simulation time of the case studies has decreased between 52 to 94 percent compared to computational fluid dynamics and faster than real-time simulation has been achieved on a conventional computer system.

کلیدواژه‌ها [English]

  • Fast Fluid Dynamics
  • computational fluid dynamics
  • Fluid flow simulation
  • ventilation
  • Building energy simulation
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