1.1 本试验方法包括常规柴油燃料油、含有十六烷值改进剂添加剂的柴油燃料油衍生十六烷值的定量测定，适用于规范的典型产品 D975 ，1-D级和2-D级常规、低硫和超低硫柴油，欧洲标准EN590，以及加拿大标准CAN/CGSB-3.517、CAN/CGSB-3.520和CAN/CGSB-3.522。该试验方法可用于定量测定生物柴油、含有生物柴油材料的柴油燃料油混合物的衍生十六烷值（例如，规范 D975 ， D6751 和 D7467 )和柴油燃料油混合成分。 1.2 该试验方法利用一个定容燃烧室，将燃料直接喷射到加热的压缩合成空气中。由样品的燃烧产生动态压力波。 一个方程将根据动态压力曲线确定的点火延迟和燃烧延迟转换为导出的十六烷值（DCN）。 1.3 该试验方法包括1.9范围内的点火延迟 ms到25 ms，燃烧延迟范围为2.5 ms到160 毫秒（30 DCN至70 DCN）。然而，所述精度仅涵盖从38.45到64.35的DCN结果范围。 1.4 以国际单位制表示的数值应视为标准。本标准不包括其他计量单位。 1.5 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 通过该试验方法确定的ID和CD值以及DCN值提供了压燃式发动机中使用的柴油燃料油的点火特性的测量值。 5.2 该测试可供发动机制造商、炼油商和营销人员使用，也可在商业中用作规范辅助，以关联或匹配燃料和发动机。 5.3 柴油燃料油DCN测定与全尺寸、变速、可变负载柴油发动机性能的关系尚不完全清楚。 5.4 该试验可应用于非常规柴油燃料。 5.5 该测试确定了点火特性，需要大约370个样本 mL，测试时间约为30 min使用适合使用的仪器。

1.1 This test method covers the quantitative determination of the derived cetane number of conventional diesel fuel oils, diesel fuel oils containing cetane number improver additives, and is applicable to products typical of Specification D975 , Grades No.1-D and 2-D regular, low and ultra-low-sulfur diesel fuel oils, European standard EN590, and Canadian standards CAN/CGSB-3.517, CAN/CGSB-3.520, and CAN/CGSB-3.522. The test method may be applied to the quantitative determination of the derived cetane number of biodiesel, blends of diesel fuel oils containing biodiesel material (for example, Specifications D975 , D6751 , and D7467 ), and diesel fuel oil blending components. 1.2 This test method utilizes a constant volume combustion chamber with direct fuel injection into heated, compressed synthetic air. A dynamic pressure wave is produced from the combustion of the sample. An equation converts the ignition delay and the combustion delay determined from the dynamic pressure curve to a derived cetane number (DCN). 1.3 This test method covers the ignition delay ranging from 1.9 ms to 25 ms and combustion delay ranging from 2.5 ms to 160 ms (30 DCN to 70 DCN). However, the precision stated only covers the range of DCN results from 38.45 to 64.35. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 The ID and CD values and the DCN value determined by this test method provides a measure of the ignition characteristics of diesel fuel oil used in compression ignition engines. 5.2 This test can be used by engine manufacturers, petroleum refiners and marketers, and in commerce as a specification aid to relate or match fuels and engines. 5.3 The relationship of diesel fuel oil DCN determinations to the performance of full-scale, variable-speed, variable-load diesel engines is not completely understood. 5.4 This test can be applied to non-conventional diesel fuels. 5.5 This test determines ignition characteristics and requires a sample of approximately 370 mL and a test time of approximately 30 min using a fit-for-use instrument.