Spherical turbulent flame propagation of pulverized coal particle clouds and ammonia co-combustion in an O2/N2 atmosphere within a fan-stirred constant volume vessel

摘要

T he present research aims t o clarify the spherical t urbulent flame propagation behavior of co-combust ion of pulverized coal particle clouds and ammonia.A unique experimental set up was built in which coal particles can be dispersed isotropic in a t urbulent flow filed and combust ed wit h ammonia.T hrough maintaining t he thermal input from mixing combust ion same wit h from pure coal combustion on condition of 0.6 kg/m~3 by subst it ut ing part of coal combust ion t hermal input from ammonia combustion,experiments were conducted in a const ant volume spherical chamber in various turbulence intensities(u'=0.32,0.65,0.97,1.29 m/s)and ammonia lean condition(Φ=0.4,0.6,0.8)wit h a common bit uminous coal.The propagation velocities of luminous flame and flame leading edge in co-combust ion were obtained separately by analyzing luminous and OH radical images taken by two high speed cameras.The results indicat ed propagation velocities of luminous flame and flame leading edge in co-combust ion increased wit h t he rise of t urbulence intensity.Ammonia has promotion effect on coal combust ion since luminous flame propagation velocity in co-combust ion is comparable to or greater than that of pure coal combustion.