بررسی عددی آتش در ساختمان در شرایط بیشینه و کمینه تهویه طبیعی با استفاده از مدل احتراقی تولید‏فلیملت‏منیفولد

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشکده مهندسی مکانیک، دانشگاه تربیت مدرس، تهران، ایران

چکیده

زمانی که آتش درون اتاق به حالتی بحرانی می‌رسد، می‌تواند برای طبقات بالاتر خطراتی ایجاد کند. در این مقاله حالت‏ های آتش با تهویه ‏ی بیشتر و کمتر از حالت بحرانی موردبحث قرار می‏ گیرد و میدان دما، سرعت و گونه ‏های مضر بررسی می ‏شود. ساختمانی دو طبقه با استفاده از روش شبیه ‏سازی گردابه ‏های بزرگ و الگوریتم پیمپل در نرم ‏افزار اپن.فوم برای سه نرخ آزادسازی حرارت 500، 1000 و 5000 کیلووات شبیه‏ سازی و نحوه ‏ی انتشار آتش و دود به طبقه ‏ی بالا بررسی می‏ شود. به منظور تحلیل گونه‏ های سمی، از مدل احتراقی تولید‏فلیملت‏ منیفولد در شبیه‏ سازی استفاده می‏ شود و با نتایج تجربی مقایسه می‏ گردد. نتایج این مدل احتراقی کمتر از ۱۵ درصد اختلاف با نتایج تجربی دارد. با افزایش آزادسازی حرارت، طبقه‏ ی بالا بیشتر در معرض خطرات آتش‏سوزی قرار می‏ گیرد؛ مثلاً، اگر میزان آزادسازی حرارت 5000 کیلووات باشد، دما در طبقه ‏ی دوم به 390 کلوین و گونه‏ ی سمی مونواکسید کربن به 25 پی.پی.ام می رسد. حالتی که میزان دبی سوخت از 1000 کیلووات پایین‌تر باشد، طبقه‏ی بالا در معرض خطر خاصی قرار نمی‏ گیرد. در حالت کلی میزان نفوذ دی‏اکسید کربن به طبقه‏ ی دوم کمتر از حد مجاز سمی‌بودن برای انسان (25-50 پی.پی.ام) است و طبقه ‏ی دوم ازنظر گاز دی‏اکسید کربن در معرض خطر خاصی قرار نمی‏ گیرد.
 

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Numerical investigation of compartment fire under maximum and minimum of natural ventilation using flamelet generated manifold combustion model

نویسندگان [English]

  • mohamad safarzadeh
  • Ghassem Heidarinejad
  • Hadi PasdarShahri
Tarbiat Modares University
چکیده [English]

When the fire in the room reaches a critical state, the fire can create hazards for the upper floors. In this paper, different fire cases with more and less natural ventilation than the critical state are discussed, and the temperature, velocity, and toxic species are discussed. A two-floor building is simulated using a large eddy simulation and PIMPLE algorithm and how the fire spreads upstairs is examined. Fuel flow rates are considered at three heat release rates of 500, 1000 and 5000 kW. The flamelet-generated-manifold combustion model is used to analyze toxic species and the results are compared with the experimental results. The relative error is less than 15%. With increasing fuel heat release rates, the upper floor is more exposed to fire hazards such that if the heat release rate is 500 kW, the temperature in the second floor reaches 390 K and the CO species reaches 25 ppm. But if the heat release rate is below 1000 kW, the upper floor will not be at particular risk. Generally, the level of diffusion of CO2 into the second floor is lower than the toxicity level for humans (25-50 ppm) and the second floor is not endangered for CO2 gases.

کلیدواژه‌ها [English]

  • Compartment fire
  • Large eddy simulation
  • Natural ventilation
  • Flamelet generated manifold combustion model

مراجع

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نشریه مهندسی مکانیک امیرکبیر
دوره 53، شماره 5 (Special Issue)
مرداد 1400
صفحه 3335-3350

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