In the present paper,a sensitivity analysis of pollutants and pattern factor in a model combustor due to changes in the geometrical characteristics of stabilizing jets has been carried out.The exhaust pollutants inclu...In the present paper,a sensitivity analysis of pollutants and pattern factor in a model combustor due to changes in the geometrical characteristics of stabilizing jets has been carried out.The exhaust pollutants including NO_(x),CO and soot have been chosen due to their harmful effect on the environment.The pattern factor has been also considered owing to its impact on turbine blades.The geometrical characteristics comprise diameter,angle and position of stabilizing jets.Eulerian-Lagrangian approach has been employed to model liquid fuel injection and distribution,breakup and evaporation of droplets.For the analysis of reactive-spray flow characteristics,RANS approach,realizable k-εturbulence model,discrete ordinates radiative heat transfer model and steady flamelet combustion model together with the chemical reaction mechanism of diesel fuel(C_(10)H_(22))have been applied.NO_(x) modeling has been performed via post-processing.Sensitivity analysis is such that by making variations in the problem inputs(diameter,angle and position of jets)in an organized manner,the effects on the outputs(NO_(x),CO,soot and pattern factor)are predicted.The number and order of simulations are predicted by design of experiments and full factorial model.Results have been analyzed using analysis of variance.It has been observed that if interactions among the characteristics of jets are considered,it is possible to analyze the exhaust pollutants more accurately.In fact,by using the interactions,it is likely to find a point where all output parameters are improved.Results show that by considering interactions of stabilizing jet characteristics,the maximum values of NO_(x),CO,soot and pattern factor change from 13.927 ppm,11.198%mole fraction,2.877 ppm and 0.043 to 26.233 ppm,14.693%mole fraction,142.357 ppm and 0.060,respectively.Furthermore,the minimum values change from 5.819 ppm,7.568%mole fraction,0.013 ppm and 0.029 to 6.098 ppm,5.987%mole fraction,0.002 ppm and 0.027,respectively.展开更多
文摘In the present paper,a sensitivity analysis of pollutants and pattern factor in a model combustor due to changes in the geometrical characteristics of stabilizing jets has been carried out.The exhaust pollutants including NO_(x),CO and soot have been chosen due to their harmful effect on the environment.The pattern factor has been also considered owing to its impact on turbine blades.The geometrical characteristics comprise diameter,angle and position of stabilizing jets.Eulerian-Lagrangian approach has been employed to model liquid fuel injection and distribution,breakup and evaporation of droplets.For the analysis of reactive-spray flow characteristics,RANS approach,realizable k-εturbulence model,discrete ordinates radiative heat transfer model and steady flamelet combustion model together with the chemical reaction mechanism of diesel fuel(C_(10)H_(22))have been applied.NO_(x) modeling has been performed via post-processing.Sensitivity analysis is such that by making variations in the problem inputs(diameter,angle and position of jets)in an organized manner,the effects on the outputs(NO_(x),CO,soot and pattern factor)are predicted.The number and order of simulations are predicted by design of experiments and full factorial model.Results have been analyzed using analysis of variance.It has been observed that if interactions among the characteristics of jets are considered,it is possible to analyze the exhaust pollutants more accurately.In fact,by using the interactions,it is likely to find a point where all output parameters are improved.Results show that by considering interactions of stabilizing jet characteristics,the maximum values of NO_(x),CO,soot and pattern factor change from 13.927 ppm,11.198%mole fraction,2.877 ppm and 0.043 to 26.233 ppm,14.693%mole fraction,142.357 ppm and 0.060,respectively.Furthermore,the minimum values change from 5.819 ppm,7.568%mole fraction,0.013 ppm and 0.029 to 6.098 ppm,5.987%mole fraction,0.002 ppm and 0.027,respectively.
