为研究高原环境下道路坡度对车辆比功率(vehicle specific power, VSP)、NOx和CO_(2)的影响,利用车载排放测试系统对轻型柴油车进行实际道路试验。试验结果表明:忽略坡度对VSP的数值大小造成差异,引起VSP分布趋势变化。在坡度10%范围内...为研究高原环境下道路坡度对车辆比功率(vehicle specific power, VSP)、NOx和CO_(2)的影响,利用车载排放测试系统对轻型柴油车进行实际道路试验。试验结果表明:忽略坡度对VSP的数值大小造成差异,引起VSP分布趋势变化。在坡度10%范围内,考虑坡度与忽略坡度的VSP差值和坡度具有较强相关性。当道路坡度绝对值小于1时,可以忽略坡度计算VSP值。忽略坡度的VSP对划Bin区间造成聚集,扰乱了Bin区间与排放相关性;忽略坡度Bin区间排放值更接近于平均排放值。考虑坡度计算的VSP值与NOx、CO_(2)排放速率有较好的相关性。展开更多
This paper concerns the study of the influence of the proportion of plastic from polyethylene, on the yields of gas emissions during the combustion of the mixture of “millet stalks and polyethylene plastic bags”, in...This paper concerns the study of the influence of the proportion of plastic from polyethylene, on the yields of gas emissions during the combustion of the mixture of “millet stalks and polyethylene plastic bags”, in a prototype of kiln of potters. During these investigations, we looked at the rate of residual oxygen (O2) and emissions of carbon dioxide (CO2) and nitrogen monoxide (NO), as a function of primary air flow (Q1) and secondary airflow (Q2). The potter’s kilns are considered those fueled by natural air flow. The primary air flows ranging from 45 to 85 Nm3?h 1 and secondary air flows from 20 to 60 Nm3?h 1. To conduct this numerical study, the model used is “reactor” based on the code CHEMKIN II. The modeled area is composed into a multitude of perfectly stirred reactors (PSR) and the kinetic model has 893 species and 113 reversible chemical reactions. The results show that in our test conditions, the increasing of the rate of plastic in the mixture produces a decrease of the residual oxygen content, due to higher oxygen consumption regardless of the airflow. The CO2 emissions are an increasing function of the rate of plastic (polyethylene) in the fuel mixture. Finally, NO emissions are increasing functions of the mass of plastic for a proportions less than or equal to 20%, and are essentially controlled by the temperature of the reactional medium.展开更多
Two-wheeler vehicles are an important mode of transportation in developing countries. However, the emissions from two-wheeler vehicles are significant. Urban two-wheeler vehicles with gasoline-fueled engines produce N...Two-wheeler vehicles are an important mode of transportation in developing countries. However, the emissions from two-wheeler vehicles are significant. Urban two-wheeler vehicles with gasoline-fueled engines produce NOx and particulate matter emissions that affect urban air quality. During traffic light stops and programmed stops, for instance, pollutants are emitted and are dangerous to human health. In this experimental study, two-wheeler vehicles with different makes, technologies and engine capacities were tested for exhaust emissions including gravimetric and online measurements at different engine speeds and a no load condition at a simulated traffic junction. Gravimetric measurements were performed by collecting the particulate mass （at two engine speeds： 1500 and 2500 rpm） from a diluted engine-out exhaust on quartz filter paper. Next, these collected particulates were used to determine the presence of metals, as well as the benzene soluble organic fraction （BSOF）. The total particulate mass, BSOF and trace elements were slightly higher at a higher engine speed （2500 rpm）. Online measurements were performed by sampling the engine exhaust （at four engine speeds： 1500, 2000, 2500, and 3000rpm） and using online instruments to determine the particle number and size distribution, the particle-bound polyaromatic hydrocarbons （PAHs）, the gaseous emissions and the smoke opacity. Engines with higher cubic capacity emitted a higher concentration of nano-particles. The particle-bound PAH concentration increased as the engine speed increased, but this concentration was notably low for the highest engine speed tested （3000 rpm）. The regulated gaseous emissions increased as the engine speed increased for all vehicles.展开更多
文摘为研究高原环境下道路坡度对车辆比功率(vehicle specific power, VSP)、NOx和CO_(2)的影响,利用车载排放测试系统对轻型柴油车进行实际道路试验。试验结果表明:忽略坡度对VSP的数值大小造成差异,引起VSP分布趋势变化。在坡度10%范围内,考虑坡度与忽略坡度的VSP差值和坡度具有较强相关性。当道路坡度绝对值小于1时,可以忽略坡度计算VSP值。忽略坡度的VSP对划Bin区间造成聚集,扰乱了Bin区间与排放相关性;忽略坡度Bin区间排放值更接近于平均排放值。考虑坡度计算的VSP值与NOx、CO_(2)排放速率有较好的相关性。
文摘This paper concerns the study of the influence of the proportion of plastic from polyethylene, on the yields of gas emissions during the combustion of the mixture of “millet stalks and polyethylene plastic bags”, in a prototype of kiln of potters. During these investigations, we looked at the rate of residual oxygen (O2) and emissions of carbon dioxide (CO2) and nitrogen monoxide (NO), as a function of primary air flow (Q1) and secondary airflow (Q2). The potter’s kilns are considered those fueled by natural air flow. The primary air flows ranging from 45 to 85 Nm3?h 1 and secondary air flows from 20 to 60 Nm3?h 1. To conduct this numerical study, the model used is “reactor” based on the code CHEMKIN II. The modeled area is composed into a multitude of perfectly stirred reactors (PSR) and the kinetic model has 893 species and 113 reversible chemical reactions. The results show that in our test conditions, the increasing of the rate of plastic in the mixture produces a decrease of the residual oxygen content, due to higher oxygen consumption regardless of the airflow. The CO2 emissions are an increasing function of the rate of plastic (polyethylene) in the fuel mixture. Finally, NO emissions are increasing functions of the mass of plastic for a proportions less than or equal to 20%, and are essentially controlled by the temperature of the reactional medium.
文摘Two-wheeler vehicles are an important mode of transportation in developing countries. However, the emissions from two-wheeler vehicles are significant. Urban two-wheeler vehicles with gasoline-fueled engines produce NOx and particulate matter emissions that affect urban air quality. During traffic light stops and programmed stops, for instance, pollutants are emitted and are dangerous to human health. In this experimental study, two-wheeler vehicles with different makes, technologies and engine capacities were tested for exhaust emissions including gravimetric and online measurements at different engine speeds and a no load condition at a simulated traffic junction. Gravimetric measurements were performed by collecting the particulate mass （at two engine speeds： 1500 and 2500 rpm） from a diluted engine-out exhaust on quartz filter paper. Next, these collected particulates were used to determine the presence of metals, as well as the benzene soluble organic fraction （BSOF）. The total particulate mass, BSOF and trace elements were slightly higher at a higher engine speed （2500 rpm）. Online measurements were performed by sampling the engine exhaust （at four engine speeds： 1500, 2000, 2500, and 3000rpm） and using online instruments to determine the particle number and size distribution, the particle-bound polyaromatic hydrocarbons （PAHs）, the gaseous emissions and the smoke opacity. Engines with higher cubic capacity emitted a higher concentration of nano-particles. The particle-bound PAH concentration increased as the engine speed increased, but this concentration was notably low for the highest engine speed tested （3000 rpm）. The regulated gaseous emissions increased as the engine speed increased for all vehicles.
