This work presents a new technique for evaluating the solid-liquid phase transformations in complex diesel fuel blends and diesel surrogates under high-pressure conditions intended to simulate those occurring in vehicle fuel injectors. A high-pressure apparatus based on a visual identification of freezing and thawing has been designed and built to monitor phase behavior and determine the crystallization temperature of complex fuels to predict wax precipitation. The proposed methodology was validated using pure substances-n-hexadecane (C16H34), cyclohexane (C6H12), and a mixture of 0.5848 mol fraction n-hexadecane in cyclohexane. The crystallization temperatures of these compounds were measured from atmospheric pressure to 400 MPa for temperatures varying from 290 K to 363 K and compared to those reported in the literature. The standard error of the estimated temperatures for the experimental data obtained in this work, based on a given pressure, was compared to data from the literature. This methodology will be extended to investigate the properties of more complex fuel mixtures.

中文翻译：

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用于监测固液相变的高压装置

这项工作提出了一种新技术，用于评估复杂柴油混合物和柴油替代品在高压条件下的固液相变，旨在模拟车辆燃料喷射器中发生的那些。已经设计并建造了一种基于冷冻和解冻视觉识别的高压装置，以监测相行为并确定复杂燃料的结晶温度以预测蜡沉淀。使用纯物质正十六烷 (C16H34)、环己烷 (C6H12) 和 0.5848 摩尔分数正十六烷在环己烷中的混合物验证了所提出的方法。这些化合物的结晶温度在大气压至 400 MPa 范围内测量，温度范围为 290 K 至 363 K，并与文献中报道的温度进行比较。在此工作中获得的实验数据的估计温度的标准误差，基于给定的压力，与文献中的数据进行了比较。这种方法将扩展到研究更复杂的燃料混合物的特性。