2008 Volume 50 Issue 153 Pages 264-270
To apply DME fuel to existing heavy oil boilers, technology that attains the luminous combustion is vital for maintaining the radiant heat transfer. Through this research, a simple method with installation of circular conic shroud on the burner tip is proposed to realize the luminous DME flame. By attaching the optimum-designed shroud, DME spray flame becomes more radiative, and the intensity of radiant heat transfer is increased. Measurements of PM (Particulate Matter) size distribution prove the formation of soot from DME in the luminous flame. Attaching a shroud induces the inhibition of mixing DME spray and circulation flow beside the burner tip, and a fuel-rich area is formed near the burner. As a result of the flow field change, in comparison to a conventional burner, a wider area for thermal decomposition of DME and formation of soot is attained. The improvement of radiant heat transfer of this luminous combustion method is confirmed by application test to the actual boiler.