The effects of nanoparticles on absorption heat and mass transfer performance in NH3/H2O binary nanofluids

The objectives of this paper are to examine the effect of nanoparticles on the pool type absorption heat transfer enhancement and to find the optimal conditions to design a highly effective compact absorber for NH3/H2O absorption system. The binary nanofluids which mean binary mixture with nano-sized particles are tested to apply nanofluids to the absorption system. Al2O3 and carbon nanotube (CNT) particles are added to make the binary nanofluids in the binary mixture of NH3/H2O. The effect of Al2O3 nanoparticles and CNT on the absorption performance is studied experimentally. The experimental ranges of the key parameters are 20% of NH3 concentration, 0–0.08 vol% (volume fraction) of CNT particles, and 0–0.06 vol% of Al2O3 nanoparticles. For the NH3/H2O nanofluids, the heat transfer rate and absorption rate with 0.02 vol% Al2O3 nanoparticles were found to be 29% and 18% higher than those without nanoparticles, respectively. It is recommended that the concentration of 0.02 vol% of Al2O3 nanoparticles be the best candidate for NH3/H2O absorption performance enhancement in the present conditions. It is expected that this study will give some basic idea to understand the heat and mass transfer enhancement mechanism in multi-components nanofluids.