الفهرس | Only 14 pages are availabe for public view |
Abstract New strategies have been developed in the design of combustion system, to over come to the environmental concern and the realization of harmful effects of the pollutants emerging from combustion systems burning fossil fuels. These strategies take seriously into account the reduction of NOx and CO levels, maintaining high combustion efficiency, wider stability limits and safety. Recently Staged combustion has been suggested as one of the most effective way of reducing the NOx emissions, maintaining other pollutants at low levels. The present thesis alms to provide a comprehensive experimental study of flame characteristics (temperature and emission) of staged swirl low NOx gaseous burner. This burner configuration is a replacement of the traditional coaxial burner. The proposed configuration allows for better control of the degree of mixing by varying the swirl angles, varying fuel jet angles and varying equivalent ratios of outer stream The present experimental program is divided into three distinct stages namely; the flame stability, in- flame measurements and exhaust emissions. Comprehensive mapping of the lean blowout equivalence ratio of the outer stream lPout with the overall lean blowout equivalence ratio lPoverall and gaseous exhaust emissions NOx and CO at varying geometrical and operation parameters are executed. These parameters include: (i) the outer stream equivalence ratio lPout, (ii) swirl angle, (iii) fuel jet nozzle angle. The overall equivalence ratio lPoverall kept constant. The result of the present work showed that: • The overall equivalence ratio ct>overall =0.85 together with (ct>out= 0.3 and 0.5) satisfy all operating conditions. • By increasing fuel jet angle reduces the NOx and CO emissions. • The present design of the burner allowed to control of flame shape, size and type by changing a swirl angle and/or a fuel jet angle. |