1.1 该自动实验室测试方法涵盖了常规柴油、油砂基燃料、碳氢化合物油、含生物柴油材料的燃料混合物、含十六烷值改进剂添加剂的柴油燃料油的点火特性的定量测定，适用于ASTM规范的典型产品 1975年 1-D S15号、1-D S500号和1-D S5000号柴油，2-D S15、2-D S500和2-D S5000级柴油，欧洲标准EN 590，加拿大标准CAN/CGSB-3.517和3.520。该试验方法也可用于定量测定柴油混合组分的点火特性。 1.2 本试验方法测量直接喷射到含有加热压缩空气的定容燃烧室中的柴油的点火延迟。 用试验方法测定十六烷值与点火延迟相关的方程式 D613型 得到衍生十六烷值（DCN）。 1.3 该测试方法涵盖了2.64 太太 至6.90 毫秒（75.1 DCN至31.5DCN）。燃烧分析仪可以测量更短和更长的点火延迟，但精度可能会受到影响。对于这些较短或较长的点火延迟，DCN的相关方程如下 附录X2 . 1.4 为了确定与本试验方法参数的一致性，应根据实践中的舍入方法，将观测值或计算值舍入为表示参数时使用的最后一位右手数字中的“最接近单位” 第29页 . 1.5 以国际单位制表示的值应视为标准值。 本标准不包括其他测量单位。 1.6 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建立适当的安全、健康和环境实践，并确定监管限制的适用性。 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《国际标准、指南和建议制定原则决定》中确立的国际公认标准化原则制定的。 =====意义和用途====== 5.1 通过该测试方法确定的ID和DCN值可以提供压燃式发动机中柴油燃料油点火特性的测量。 5.2 该测试可在商业中用作规范辅助，以关联或匹配燃料和发动机。它也可用于研究或在本试验方法的条件下对柴油的点火延迟感兴趣时。 5.3 柴油燃料油DCN测定与全尺寸、变速、可变负荷柴油发动机性能的关系尚不完全清楚。 5.4 该试验可适用于非常规燃料。人们认识到，不完全了解全尺寸发动机中非常规燃料的性能。因此，提醒用户调查点火特性测量值对预测这些类型燃料的全尺寸发动机性能的适用性。 5.5 该测试确定点火特性，需要在适合使用的仪器上进行约100 mL的样品和约20分钟的测试时间。

1.1 This automated laboratory test method covers the quantitative determination of the ignition characteristics of conventional diesel fuel oil, oil-sands based fuels, hydrocarbon oils, blends of fuel containing biodiesel material, diesel fuel oils containing cetane number improver additives, and is applicable to products typical of ASTM Specification D975 grades No. 1-D S15, No. 1-D S500, and No. 1-D S5000, and grades No. 2-D S15, No. 2-D S500, and No. 2-D S5000 diesel fuel oils, European standard EN 590, and Canadian standards CAN/CGSB-3.517 and 3.520. The test method may also be applied to the quantitative determination of the ignition characteristics of diesel fuel blending components. 1.2 This test method measures the ignition delay of a diesel fuel injected directly into a constant volume combustion chamber containing heated, compressed air. An equation correlates an ignition delay determination to cetane number by Test Method D613 , resulting in a derived cetane number (DCN). 1.3 This test method covers the ignition delay range from 2.64 ms to 6.90 ms (75.1 DCN to 31.5 DCN). The combustion analyzer can measure shorter and longer ignition delays, but precision may be affected. For these shorter or longer ignition delays the correlation equation for DCN is given in Appendix X2 . 1.4 For purposes of determining conformance with the parameters of this test method, an observed value or a calculated value shall be rounded “to the nearest unit” in the last right-hand digit used in expressing the parameter, in accordance with the rounding method of Practice E29 . 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 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. 1.7 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 DCN values determined by this test method can provide a measure of the ignition characteristics of diesel fuel oil in compression ignition engines. 5.2 This test can be used in commerce as a specification aid to relate or match fuels and engines. It can also be useful in research or when there is interest in the ignition delay of a diesel fuel under the conditions of this test method. 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 may be applied to non-conventional fuels. It is recognized that the performance of non-conventional fuels in full-scale engines is not completely understood. The user is therefore cautioned to investigate the suitability of ignition characteristic measurements for predicting performance in full-scale engines for these types of fuels. 5.5 This test determines ignition characteristics and requires a sample of approximately 100 mL and a test time of approximately 20 min on a fit-for-use instrument.