Evaluation of Thermophysical Properties of Menthol-Based Deep Eutectic Solvent as a Thermal Fluid: Forced Convection and Numerical Studies

Abstract

Concentrated Solar Power (CSP) is one of the emerging renewable energy technology, where sunlight is concentrated from a large area and are stored in a collector filled with heat transfer fluid (HTF). The current work reports the synthesis of novel HTF based on menthol based deep eutectic solvents (DES). DES consisting of a hydrogen bond acceptor (HBA) namely DL-menthol and a hydrogen bond donor (HBD) (oleyl alcohol) has been prepared and explored to evaluate its effectiveness as a thermal fluid. The thermal properties namely viscosity, density, thermal conductivity and heat capacity are measured and compared with both conventional and commercial solvents within the temperature range T=298.15-353.15 K. The density of DES was found to decrease with increase in temperature while the rheological measurements suggest a Newtonian fluid with its shear viscosity decreasing exponentially with increasing temperature. The thermal conductivity of the DES was found to be ~0.161 W/m.K, which decreases linearly with te...