Combustion and emission characteristics of BD20 reformed by ultrasonic energy for different injection delay and EGR rate in a diesel engine

The purpose of this study is to understand the operational characteristics of a diesel engine that uses BD20 reformed by ultrasonic energy irradiation. In particular we study the effects of tuning injection delay and EGR rate. BD containing about 10% oxygen has attracted attention due to soaring crude oil prices and environmental pollution. This oxygen decreases soot by promoting combustion, but it also increases NOx. To solve this problem, injection timing may be delayed or an EGR system may be applied. These adjustments normally lower engine power and increase exhaust emission but, in using fuel reformed by ultrasonic energy irradiation (which is changed physically and chemically to promote combustion), we may hope to circumvent this problem. To control the duration of the ultrasonic energy irradiation, the capacity of the chamber in an ultrasonic energy fuel supply system was tested at 550cc and 1100cc capacities. As for the results of the experiment, we could identify the optimum EGR rate by investigating the engine performance and the characteristics of exhaust emissions according to the injection timing and the EGR rate while ultrasonically irradiated BD20 was fed to a commercial diesel engine. With UBD20 (at an injection timing of BTDC 16°), the optimum EGR rate, giving satisfactory engine performance and exhaust emissions characteristics, was in the range of 15∼20%.     

多功能海上重吊船LNG燃料应用分析

基于某多功能海上重吊船液化天然气（Liquefied Natural Gas，LNG）双燃料系统的设计，结合其典型运营工况，采用经济性（Economic Performance，EP）分析方法对LNG燃料和低硫船用轻质柴油（Low Sulfur Marine Gas Oil，LSMGO）燃料的能量消耗、额外初始投入成本、运营成本（Operating Expense，OPEX）等进行分析比较。结果表明，在满足设计要求的前提下，在中长期的船舶运维周期内，LNG燃料的EP更好。考虑未来船用清洁燃料的发展，相关研究可为海上工程作业船舶的燃料动力系统的设计和选择提供思路。     

P3E/C 软件在巴基斯坦集装箱深水港防波堤工程中的应用

阐述巴基斯坦集装箱深水港防波堤工程采用Primavera 公司P3E/C 项目管理软件的必要性。介绍该软件的功能和特点，结合该防波堤工程，总结P3E/C 软件应用于工程所需的准备工作，并论述该软件在工程进度控制、费用控制、质量控制和安全文明施工控制方面的具体应用。应用P3E/C 软件有助于企业信息化、专业化和标准化的项目管理体系的建立。