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In this study, a molten salt-based high temperature nanofluid is explored for solar thermal energy conversion applications. The efficacy of the nanofluid as a heat transfer fluid (HTF) in concentrating solar power systems is explored in this study. The molten salt can enable higher operating temperature resulting in enhancement of the overall system efficiency for power generation (using, for example, a Rankine cycle or Stirling cycle). However, the usage of the molten salt as the HTF is limited due to their low specific heat capacity values (compared with, for example, water or silicone oils). The low specific heat of molten salt can be enhanced by doping small amount of nanoparticles. Solvents doped with minute concentration of nanoparticles are termed as "Nanofluids." Nanofluids are considered as attractive coolants for thermal management applications due to their anomalously enhanced thermal properties (compared with the neat solvent).

Poly Alpha Olefins (PAO) are extensively used as cooling fluid for thermal management in avionics cooling applications owing to their superior physical and chemical properties, such as greater fluidity at low temperature, lower volatility, a higher viscosity index, lower pour point, better oxidative and thermal stability as well as low toxicity. Solvents doped with minute concentration of nanoparticles are termed as “Nanofluid”. Anomalous enhancements in thermo-physical property values as well as in heat transfer performance of nanofluids have been reported using nanofluids (compared to that for the neat solvent). The thermal interfacial resistance between the nanoparticle and the solvent molecules (Kapitza Resistance) is the dominant factor controlling the efficacy of the nanofluids for cooling applications.

The thermal characteristic of nanofluid for flow in a micro-channel is reported in this study by using an array of temperature nano-sensors. In this study, K-Type Thermocouples (Chromel/Alumel) were fabricated by surface micromachining process on a silicon wafer to obtain the thin film thermocouple array (TFTA). The micro-channel with TFTA was mounted on a heater (calorimeter) for imposing a specified heat flux on the bottom surface of the micro-channel. De-ionized water (DIW) was used as the test fluid for recording the temperature profile on the wafer substrate at different flow rates and heat fluxes. Aqueous nanofluids containing alumina nanoparticles were then used to record the temperature profiles under similar heat flux and flow conditions. The temperature profile was measured with the TFTA in a linear array of 5 columns and 2 rows of sensors while the volume flow rate was varied from 5 μl/min, to 7 μl/min and to 9 μl/min.

The often-observed differences in nitrogen oxides, or NOx, emissions between biodiesel and petroleum diesel fuels in diesel engines remain intense topics of research. In several instances, biodiesel-fuelled engines have higher NOx emissions than petroleum-fuelled engines; a situation often referred to as the "biodiesel NOx penalty." The literature is rich with investigations that reveal many fundamental mechanisms which contribute to (in varying and often inverse ways) the manifestation of differences in NOx emissions; these mechanisms include, for example, differences in ignition delay, changes to in-cylinder radiation heat transfer, and unequal heating values between the fuels. In addition to fundamental mechanisms, however, are the effects of "system-response" issues.