Thermal performance of ionic liquids for solar thermal applications

Abstract

a b s t r a c tExperimental investigations were carried out to evaluate thermophysical properties, i.e. density, viscosity, heat capacity, and thermal conductivity and high temperature forced convection behavior of N-butyl-N,N,N-trimetylammoniumbis(trifluormethylsulfonyl)imide ([N 4111 ][NTf 2 ]) ionic liquid (IL) for its potential application in concentrated solar power (CSP). Results from the experiments will be useful in assessing the potential of using ILs for solar thermal collectors. Experimental results show that thethermal conductivity was slightly decrease with the increase of temperature; vary from 0.124 to 0.121 W/m K for a change in temperature of 283-343 K, strong temperature effect on the viscosity of IL was observed and maintain an exponential relationship with the temperature; heat capacity increases linearly with temperature measured from 298 to 618 K. Forced convection performance of the IL was studied in a circular tube under both in laminar and turbulent conditions. Although the heat transfer coefficient of the IL was found to be lower compared to the De-Ionized (DI) water, its thermal stability and other attractive properties may make it a viable candidate for solar collector use. Our experimental results also established that Shah's equation and Gnielinski's equation can predict forced convection performance of IL for both the laminar region and turbulent region respectively.

Enhanced thermophysical properties of NEILs as heat transfer fluids for solar thermal applications

“…Fox et al [17] have studied different nanoparticles effect on thermophysical properties of NEILs and reported that whisker-shaped Al 2 O 3 nanoparticles show highest thermal conductivity enhancement. Paul et al [18][19] have reported the higher forced convection heat transfer coefficients [18] and deterioration of the natural convection [19]…”

Ionic Liquids-Based Nanocolloids—A Review of Progress and Prospects in Convective Heat Transfer Applications

“…Only a handful of experimental works from a single research group on convective heat transfer of ILs and their nanofluids (INFs) are reported in the literature [62,[77][78][79][80]. The findings of those works are summarized in Table 7.…”

Istraživanje Strujanja Jonske Tečnosti Primenom Računarske Dinamike Fluida

“…Naučnici 2008. godine otkrivaju da toplotna provodljivost jonske tečnosti ima veoma malu zavisnost od molske frakcije CO 2 , kada je u pitanju jonska tečnosti na bazi imidazolijuma [2]. Grupa naučnika radila je eksperimentalno istraživanje termo-fizičkih osobina jonske tečnosti [N 4111 ][NTf 2 ], za njenu potencijalnu primenu u centralnim solarnim kolektorima [3]. Iako je koeficijent prenosa toplote niži nego kod destilovane vode, njena toplotna stabilnost i druga svojstva čine je kandidatom za korišćenje u solarnim elektranama.…”

“…Za potvrdu tačnosti rezultata numeričke simulacije vrši se verifikacija poznatim podacima iz literatura i rezultatima prethodnih eksperimentalnih istraživanja. Eksperimentalni podaci dobijeni predhodnim istraživanjem [3] pokazuju da se jonska tečnost, kao i voda, ponaša kao Njutnovski fluid. Takođe jonska tečnost ima iste trednove promene fizičkih svojstava sa temperaturom kao i voda.…”