• Yaseen, Mohammed
• Saleemia, Samia
• Rateb, Mostafa
• Hursthouse, Andrew

Abstract

The continuous increase in the requirement for energy efficient heating systems requires the use of novel formulations for improved heat transfer in for example domestic central heating systems. In this review the influence of surfactants such as Alkyl Poly Glycosides (APG) on heat transfer efficiency is investigated and their physical characteristics presented. Unlike nonionic ethoxy surfactants, the hydrophilic moiety of alkyl poly glucosides arises solely from the saccharide head group. APG have received increasing attention due to their compatibility and synergistic effects when combined with other surfactants, as well as their relatively low toxicity and minimal environmental impact.<br/><br/>The potential application of other heat transfer additives to water is also presented in an effort to determine routes to improving heat transfer properties of APG. Other agents for improving heat transfer include surfactants, salts, nanoparticles and polymers. These improved formulations have the potential to enhance the effectiveness of APG by the synergistic combination of enhanced water structure and the improvement of surface interaction.<br/><br/>Analysis of commercial Endotherm mixture was found to contain the single sugar unit, n-Octyl-β-D-Glucopyranoside, n-Decyl-β-D-Glucopyranoside with smaller amounts of the two maltose sugar alkyl polyglycosides. The Endotherm mixture produced a surface tension of around 28mN/m, this was found to be more surface active than any of the pure alkyl polyglycosides. This mixture was 19.2% more efficient at heating compared to pure water and the formulation of Acacia Gum to the Endotherm solution resulted in a slower cooling. Further work toward the development of more effective formulations is suggested to enhance APG thermal transfer. <br/>

Topics

• nanoparticle
• impedance spectroscopy
• surface
• polymer
• toxicity
• surfactant