مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

بررسی تجربی اثر مشخصه‌های جریان ورودی و طول محفظه بر دینامیک شعله پیش‌آمیخته جزئی در راکتورهای ابعاد مزو استوانه‌ای شکل با قطر ثابت و طول‌های مختلف

نوع مقاله : پژوهشی اصیل

نویسندگان
دانشگاه صنعتی امیرکبیر
چکیده
چکیده: در این مطالعه، به بررسی تجربی احتراق پیش‌آمیخته جزئی متان و اکسیژن خالص، درون یک راکتور کوارتز مقیاس مزو با قطر داخلی 5 میلی‌متر و ضخامت دیواره 1 میلی‌متر با طول‌های 5، 10 و 15 سانتی‌متر و نسبت اختلاط‌های 25%، 50% و 75% پرداخته شده است. نتایج آزمایش‌ها اعم از عوامل مؤثر بر رژیم‌های شعله، محدوده تشکیل هر کدام، دینامیک شعله و توزیع دمای دیواره خارجی راکتور‌، تحلیل و گزارش شده است. آزمون‌های فوق در محفظه احتراق استوانه‌ای هم‌مرکز متقارن‌محوری و در رژیم جریان آرام صورت گرفته است. در اکثر آزمایش‌ها، رژیم شعله نوسانی بوده و همین عامل باعث گردیده تا توزیع حرارت یکنواخت‌تری در طول راکتور مشاهده گردد. دینامیک این شعله از تغییرات به ترتیب نسبت اختلاط، طول راکتور، دبی حجمی اکسیژن و نهایتاً دبی حجمی سوخت، که باعث تغییرات در سرعت جریان ورودی و نسبت هم‌ارزی می‌گردد بیشتر اثر می‌پذیرد. همچنین مشاهده شد با افزایش طول راکتور به علت فراهم شدن زمان مناسب جهت همگن شدن مخلوط، تفاوت‌ها در بازه تشکیل شعله در نسبت پیش‌اختلاط‌های مختلف کم می‌گردد.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Experimental study of the effect of inlet flow characteristics and chamber length on partially premixed flame dynamics, in the mesoscale cylindrical reactor of constant diameter with different lengths

نویسندگان English

ALi Zargarbashi
Sadegh Tabejamaat
Soroush Sarrafan Sadeghi
Soroush sheykhbaglou
Amirkabir University of Technology(Tehran Polytechnic)
چکیده English

In this paper, the experimental study of partially premixed combustion of methane and oxygen in a 5 mm mesoscale quartz reactor with 1 mm wall thickness and 5, 10, and 15 cm lengths. The partially premixed for 25%, 50%, and 75% mixing ratios paid. Experimental results including the factor of affecting flame regimes, formation range, flame dynamics, the outer wall temperature distribution of the reactor had been analyzing and reporting. The above tests were performing in an asymmetrically centered cylinder combustion chamber and a laminar flow regime. In most partial pre-mixing combustion experiments, the oscillation regime, which had an optimal heat distribution throughout the reactor, had been observed. The flame dynamics were more effect by changes in mixing ratio, reactor length, oxygen flow rate, and finally fuel flow rate (equivalence ratio). Also observed that by increasing the reactor length due to the appropriate time for homogenization of the mixture, differences in the flame formation interval were reducing in the different ratios of the pre-mixes.

کلیدواژه‌ها English

Meso Combustion
Methane
Oxygen
Partial Premixed Combustion
Flame Dynamics
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