Nanofluid heat capacities

Abstract

Significant increases in the heat capacity of heat transfer fluids are needed not only to reduce the costs of liquid heating and cooling processes, but also to bring clean energy producing technologies like concentrating solar power (CSP) to price parity with conventional energy generation. It has been postulated that nanofluids could have higher heat capacities than conventional fluids. In this work, nano- and micron-sized particles were added to five base fluids (poly-α olefin, mineral oil, ethylene glycol, a mixture of water and ethylene glycol, and calcium nitrate tetrahydrate), and the resulting heat capacities were measured and compared with those of the neat base fluids and the weighted average of the heat capacities of the components. The particles used were inert metals and metal oxides that did not undergo any phase transitions over the temperature range studied. In the nanofluids studied here, we found no increase in heat capacity upon the addition of the particles larger than the experimental error.

Progress of nanofluid application in solar collectors: A review

“…Some nanofluids exhibit anomalous behavior with volume concentration. Starace et al [48] reported both decrease and increase in specific heat capacity for SiO 2 nanoparticles in EG base fluid. Shahrul et al [49] performed comparative review on specific heat of nanofluids for energy applications.…”

A review on the heat and mass transfer phenomena in nanofluid coolants with special focus on automotive applications

“…DSC technique has been successfully implemented in a large number of nanofluid studies [172][173][174][175][176][177][178]. Alternatively, some researchers suggested their own experimental setups for measuring c p of nanofluids [8,179,180].…”

“…For extended reviews regarding the typical nanofluids specific heat capacity, the reader is delegated to references [175,179,190,192].…”

Prediction of nanofluids properties: the density and the heat capacity

“…However, only few of them are focused on the influence of nanoparticles on the density and heat capacity of base fluids [4][5][6][7][8][9][10][11][12][13]. Nevertheless, experimental data on the value of the excess functions for these properties provide valuable information about the structure of nanofluid and its nature as a function of the temperature and concentration of nanoparticles.…”

“…Numerous publication are devoted to different thermophysical and electrokinetic properties of nanofluids [1][2][3][4][5][6][7][8][9][10][11][12][13]. However, only few of them are focused on the influence of nanoparticles on the density and heat capacity of base fluids [4][5][6][7][8][9][10][11][12][13].…”