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191.
柴油机排气微粒冷却演变特性的实验研究 总被引:4,自引:0,他引:4
对柴油机排气微粒在冷却条件下的演变特性进行了实验研究.结果表明,排气的冷却作用对微粒的质量浓度具有重要的影响.引起微粒质量浓度变化的主要原因是排气中气态碳氢的冷凝,从而增加了微粒的质量浓度.排气的冷却促使柴油机微粒增大,分布在0.01~1.0 μm粒径范围内的微粒数量有所减少,特别是小于0.1 μm以下的小微粒,微粒数量下降的幅度相对较大,并且冷却温度越低,变化越明显.排气冷却后,0.1-1.0 μm粒径范围内的微粒体积浓度呈减少的趋势.此外,流速对排气冷却条件下的微粒演变特性亦有一定的影响,随排气流速的降低,0.01~1.0 μm粒径范围内的微粒数量浓度和体积浓度减小. 相似文献
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烟塔排烟电厂大气影响预测分析 总被引:1,自引:0,他引:1
在系统分析我国烟塔排烟电厂大气影响评价及其相关研究成果的基础上,指出应关注的几个问题,并结合烟塔排烟电厂的负荷变化特点提出了解决问题的基本思路及需要重点研究的专题。 相似文献
199.
M. Rajagopal 《International Journal of Green Energy》2016,13(11):1109-1119
A phase change material (PCM)-based flat plate modular heat exchanger for free cooling application, suitable for the diurnal temperature variation that prevails during the summer months of Bangalore city, India is designed and experimentally investigated. The flow and other parameters selected in the present study are meant to suit the accelerated charging of the PCM in the modular heat exchanger during the early morning hours, and to provide cool energy to the room during the daytime, by circulating the ambient air through the heat exchanger at a lower velocity. It is observed from the charging experiments that the decrease in the inlet air temperature has more influence in reducing the solidification time than the increase in the inlet air velocity. The heat exchanger designed in the present investigation is capable of maintaining the room temperature around 30°C for a longer duration of 8 hr when the heat load is 0.5 kW. It is suggested to design the modular heat exchanger with a surface area proportionate to the present heat exchanger size when the room heat load increases beyond 0.5 kW, in order to maintain a minimum comfortable temperature of 30°C in the room. 相似文献
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Hamid HassanzadehFard 《International Journal of Green Energy》2016,13(15):1615-1625
Meta heuristic algorithms have been introduced as a powerful method to solve the nonlinear optimization problems. These algorithms have been employed in many complex engineering problems due to their high capability in finding the solutions and reaching the optimal results within a short period of time. Optimization of distributed generation units in distribution systems, which have profoundly impacted on the system losses and voltage profile, is one of these nonlinear problems. In this study, a novel objective function was proposed for optimization procedure by meta-heuristic algorithms. The related objective function consists of the total cost of distributed generation units, cost of the purchased natural gas, cost of distribution system power losses, and penalty for greenhouse gas emissions. The electrical, cooling, and heating loads were considered in this study. In the distribution system, the waste and fuel cell were used to supply the required heating and cooling loads. The meta-heuristic algorithms including Particle Swarm Optimization (PSO), Genetic Algorithm (GA), and Imperialist Competitive Algorithm (ICA) were employed to find the optimal location and size of distributed generation units in a distribution system. A detailed performance analysis was done on 13 bus radial distribution system. The performances of three algorithms were compared with each other and results showed that the PSO was the fastest; and had the best solution and optimum results. Furthermore, the PSO reached the optimum solution in a fewer number of iterations than the GA and ICA algorithms. 相似文献