Enhancing the performance of heat transfer fluids (HTF) is a key target for improving the efficiency of many industrial processes. Employing nanofluids for this purpose, by dispersing nanoparticles into the initial HTF to improve its thermo-physical properties, is one possible way to increase its heat transfer capacity. However, testing these properties at high temperature is not always easy. An experimental setup consisting of a thermohydraulic loop for high-temperature heat transfer measurements was developed in this work. The accuracy and repeatability of the measurements taken in the heat transfer loop were ensured. A nanofluid consisting of a commercial thermal oil, doped with Sn nanoparticles at 1 wt% and olive oil surfactant used to enhance colloidal stability, was tested and compared to the results obtained for the base fluid and the base fluid/stabiliser mixture employing their experimentally measured thermo-physical properties. The nanofluid generally enhanced the convective heat transfer coefficient in relation to the base fluid with enhancements of up to 7.23% at 200 °C and 9.43% at 140 °C vs. the pure base fluid.

提高传热流体 (HTF) 的性能是提高许多工业过程效率的关键目标。为此目的使用纳米流体，通过将纳米粒子分散到初始 HTF 中以改善其热物理性质，是提高其传热能力的一种可能方法。然而，在高温下测试这些特性并不总是那么容易。在这项工作中开发了一个由用于高温传热测量的热液压回路组成的实验装置。确保了传热回路中测量的准确性和可重复性。由商业热油组成的纳米流体，掺杂有 1 wt% 的 Sn 纳米颗粒和用于增强胶体稳定性的橄榄油表面活性剂，对基液和基液/稳定剂混合物进行了测试，并使用它们实验测量的热物理特性获得的结果进行比较。纳米流体通常提高了与基础流体相关的对流传热系数，在 200 °C 时提高了 7.23%，在 140 °C 时提高了 9.43%与纯基液相比。