TY - JOUR T1 - Investigating the geometrical parameters of nozzle-mix burners form the combustion exergy points of view using Taguchi method TT - بررسی پارامترهای هندسی مشعل های مخلوط سر نازل از دیدگاه اگزرژی با استفاده تکنیک تاگوچی JF - mdrsjrns JO - mdrsjrns VL - 15 IS - 4 UR - http://mme.modares.ac.ir/article-15-2497-en.html Y1 - 2015 SP - 221 EP - 228 KW - Irreversibility KW - nozzle-mix burner KW - branched nozzle KW - Taguchi method N2 - Nozzles branching, fuel injection angle and nozzle diameter can affect the mixing process and combustion performance of nozzle-mix burners. In the current work, CFD approach and Taguchi method are employed to investigate the effects of these parameters on the irreversibility of combustion process. Combustion in nozzle-mix burner is first simulated by use of CFD method. The governing equations, including continuity, momentum, energy and chemical reactions are solved numerically by use of FLUENT. Standard k-ε and EDC models are used for modeling turbulence and interaction between chemical reactions and turbulence, respectively. Then, the developed model is experimentally investigated and numerical method is validated. Using the Taguchi method, the effects of each parameters, their priority and optimum values are determined by use of Minitab. A L9(33) orthogonal Taguchi array is used with the analysis aim of minimizing irreversibility. Results show that injection angle, number of branches and nozzle diameter have the most influence on the combustion irreversibility, respectively. The optimum configuration of the nozzle-mix burner is determined to have a 45º injection angle, 4 branches and 4mm nozzle diameter. The corresponding irreversibly to this optimum case is 45.88%. M3 ER -