Abstract

Nanofluids have been used in several thermal management systems, as they contribute to the augmentation of the heat dissipation rates in many applications, especially those where heat pipes, pulsating heat pipes and loop heat pipes are used. Long term use of this type of device is required in order to increase their reliability, which requires chemical compatibility between the base fluid and the nanoparticle. The verification of the non-condensable gases (NCGs) generation is required as the nanofluid undergoes thermal cycling and chemical reactions are present, along with the interaction with the device's housing material. The prediction of the amount of NCGs is necessary for each base fluid and nanofluid combination, which contributes to the evaluation of the life time expectancy for those devices. For this purpose, the use of the Arrhenius model is applied, which indicates the amount of NCG generated and the time related for which the HP must undergo the ageing process. As the stability of nanofluids is strongly connected to various thermal properties, devices' thermal efficiency as well as their longevity, it is also important to employ stable nanofluids in this type of thermal control device.

摘要

纳米流体已用于多种热管理系统，因为它们有助于在许多应用中提高散热率，尤其是那些使用热管、脉动热管和回路热管的应用。需要长期使用这种类型的设备以提高其可靠性，这需要基液和纳米颗粒之间的化学相容性。由于纳米流体经历热循环和化学反应，以及与设备外壳材料的相互作用，因此需要验证不可冷凝气体 (NCG) 的生成。每种基础流体和纳米流体组合都需要预测 NCG 的数量，这有助于评估这些设备的预期寿命。以此目的，应用了 Arrhenius 模型，该模型指示生成的 NCG 量以及 HP 必须经历老化过程的相关时间。由于纳米流体的稳定性与各种热性能、器件的热效率及其寿命密切相关，因此在此类热控制器件中采用稳定的纳米流体也很重要。