An experimental investigation was conducted in a 3 MW pilot-scale tangential combustion facility to explore the co-combustion characteristics of bituminous coal mixed with semi-coke.The thermal gravimetric analyzer(TG...An experimental investigation was conducted in a 3 MW pilot-scale tangential combustion facility to explore the co-combustion characteristics of bituminous coal mixed with semi-coke.The thermal gravimetric analyzer(TGA)was used to obtained fuel thermal analysis.The results presented effects of semi-coke blending ratio(BR)on average furnace temperature,ignition temperature,NO emission and combustion efficiency.The excess air coefficient in main combustion sections and outlet were fixed at 0.85 and 1.2 while BR increased from 0%to 50 wt.%.The temperature profiles of combustion decreases along the height of furnace while average furnace temperature fluctuates slightly with an increasing BR.The concentration of NO has an increasing tendency with the increasing of BR.The ignition temperature obtained from TGA measurement agreed well with experiment result.In addition,combustion efficiency was not sensitive to BR and decreased slightly with the increasing BR.展开更多
Under the back-side windy condition,the convection and radiation heat transfer characteristics in an iso-flux upward-facing cylindrical cavity were studied by three-dimensional numerical simulation.The impacts of cavi...Under the back-side windy condition,the convection and radiation heat transfer characteristics in an iso-flux upward-facing cylindrical cavity were studied by three-dimensional numerical simulation.The impacts of cavity tilt angle,wind incident angle and wind speed on convection and radiation heat transfer Nusselt number Nuc and Nur were analyzed,and the possible explanations for their impacts were presented.Results show that due to the disturbance of wind,the influence of cavity tilt angle becomes more complicated and is related to wind incident angle and wind speed.The variation of Nuc or Nur with wind incident angle is different for different cavity tilt angles.Despite of the changes of cavity tilt angle or wind incident angle,the Nuc increases with the wind speed while the Nur presents a declination with the increasing of wind speed.Hence,compared with cavity tilt angle and wind incident angle,wind speed may be the dominant factor affecting or controlling the convective and radiation heat transfer of cavity.展开更多
基金funded by National Key Research and Development Program of China(Grant No.2017YFB0602002,and Grant No.2016YFC0203700)。
文摘An experimental investigation was conducted in a 3 MW pilot-scale tangential combustion facility to explore the co-combustion characteristics of bituminous coal mixed with semi-coke.The thermal gravimetric analyzer(TGA)was used to obtained fuel thermal analysis.The results presented effects of semi-coke blending ratio(BR)on average furnace temperature,ignition temperature,NO emission and combustion efficiency.The excess air coefficient in main combustion sections and outlet were fixed at 0.85 and 1.2 while BR increased from 0%to 50 wt.%.The temperature profiles of combustion decreases along the height of furnace while average furnace temperature fluctuates slightly with an increasing BR.The concentration of NO has an increasing tendency with the increasing of BR.The ignition temperature obtained from TGA measurement agreed well with experiment result.In addition,combustion efficiency was not sensitive to BR and decreased slightly with the increasing BR.
基金funded by National Key Research and Development Program of China(Grant No.2017YFB0602002,and Grant No.2016YFC0203700)。
文摘Under the back-side windy condition,the convection and radiation heat transfer characteristics in an iso-flux upward-facing cylindrical cavity were studied by three-dimensional numerical simulation.The impacts of cavity tilt angle,wind incident angle and wind speed on convection and radiation heat transfer Nusselt number Nuc and Nur were analyzed,and the possible explanations for their impacts were presented.Results show that due to the disturbance of wind,the influence of cavity tilt angle becomes more complicated and is related to wind incident angle and wind speed.The variation of Nuc or Nur with wind incident angle is different for different cavity tilt angles.Despite of the changes of cavity tilt angle or wind incident angle,the Nuc increases with the wind speed while the Nur presents a declination with the increasing of wind speed.Hence,compared with cavity tilt angle and wind incident angle,wind speed may be the dominant factor affecting or controlling the convective and radiation heat transfer of cavity.