中文摘要：

基于双色飞秒激光抽运探测方法，本文提出一种能够快速测量液体热导率的实验方法，具有测量便捷、精度高，液体用量少等优点．该方法测量过程中液体温升小，液体自身热物性不发生变化，液体内部自然对流传热微弱，对液体热导率测量的干扰可以忽略．对测量过程中样品内部的热输运过程进行了分析，建立了用于分析测量数据的双向热输运模型，并利用该模型对可能影响测量精度的物理参数进行了敏感度分析，包括玻璃基底的热导率、铝传感层的厚度以及抽运激光的调制频率，敏感度分析可以对被测量样品的结构设计和实验条件的选取起到指导作用．利用该实验方法对水和十六烷2种液体的热导率进行了测量，测量结果分别约为0．6和0．14W／（mK），测量误差分别为2％和10％，与文献报道值吻合程度较高，验证了该实验方法的有效性．另外，该方法还适用于熔点较低的固体热导率的测量（如石蜡等），以及固一液界面热导的测量等．

英文摘要：

The ultra-fast laser pump-probe technique, which is also known as transient thermo-reflectance technique, is a non-contact experimental method widely used for measurements of thermal properties and heat transfer processes. Based on a special two-color femto-second laser pump-probe technique, a rapid experimental method for thermal conductivity measurements of liquids is described in this paper, which has many advantages such as operational convenience, high accuracy, and small liquid sample requirements. During thermal conductivity measurements, pump and probe lasers are co-axial and focused on the interface between the aluminum transducer layer and the glass substrate by a 10× objective lens. The temperature of the aluminum surface will rise immediately following illumination by the laser pulse and fall within the time interval before the next pump pulse. The surface reflectivity of aluminum is a function of temperature and is recorded by a photoelectric detector from the intensity of the reflected probe pulses. The temperature rise caused by the laser energy is small enough that the thermal properties of liquids are stable; the convection inside the liquids is also so weak that it can be ignored. In our study, the heat transfer within the sample during the measurement was analyzed using a bi-direction heat transfer model, which is described. The parameter dependences of the physical properties which may influence the measurement accuracy, including thermal conductivity of the glass substrate, the thickness of the aluminum transducer layer and the modulation frequency of the pump laser, are also analyzed using this model. The analysis shows a lower substrate thermal conductivity, a thinner aluminum transducer layer and a higher modulation frequency can increase the sensitivity of liquid thermal conductivity and reduce measurement error. This analysis will aid in designing sample structures and choosing experimental conditions. In the study, thermal conductivities of two kinds of liquid, water and hexadecane, ar