Abstract

This article presents an experimental study of colloidal solutions with a focus on the surface properties of colloidal solutions in view of their further application in pulsating heat pipes. Using a tensiometer and the Welhelmi plate method, we carried out a series of measurements of surface tension for various concentrations and temperatures of colloidal solutions with three promising surfactants: CTAB, SLS, and Tween-80. These surfactants in dry form were mixed with water to make a 1% solution and then diluted to weaker concentrations of up to \(3\cdot 10^{-8}\) mol/l. Dependences of the surface tension on the surfactant concentration were determined, which turned out to be in good agreement with data available in literature. The surface tension values were measured over the temperature range of 20 to 70°C. For several concentrations of the surfactant SLS, the first derivative of the surface tension with respect to the temperature was found to be positive (\(\partial \sigma /\partial T> 0\)), which means that the interface can be self-wetted. This property may be important in preventing formation of dry spots, which will improve heat transfer in heat pipes.

中文翻译：

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表面活性剂水溶液在脉动热管中的应用

摘要

鉴于胶体溶液在脉动热管中的进一步应用，本文介绍了胶体溶液的实验研究，重点是胶体溶液的表面特性。使用张力计和 Welhelmi 板法，我们对具有三种有前景的表面活性剂 CTAB、SLS 和 Tween-80 的胶体溶液的各种浓度和温度进行了一系列表面张力测量。这些干燥形式的表面活性剂与水混合制成 1% 的溶液，然后稀释到较弱的浓度，最高可达\(3\cdot 10^{-8}\) 摩尔/升。确定了表面张力对表面活性剂浓度的依赖性，结果与文献中可用的数据非常一致。表面张力值是在 20 到 70°C 的温度范围内测量的。对于几种浓度的表面活性剂 SLS，发现表面张力对温度的一阶导数为正 ( \(\partial \sigma /\partial T> 0\) )，这意味着界面可以是自- 湿了。这种特性对于防止形成干点很重要，这将改善热管中的热传递。