One of the important contributions to the application of nanotechnology is the nanofluids technique in which will be become a good alternative to the conventional heat transfer medium. This is done by addition of nano particles of high thermal conductivity to the base fluid of the low thermal conductivity.
In the present paper, the performance of chilled-water air conditioning unit with and without alumina nanofluids has been experimentally investigated. The first method technique was used to prepare Al2O3- water nanofluids.Al2O3 nano particles was added with water in the cooling tank through using different concentrations by weight varies from 0.1,0.2,0.3, and 1% wt. and the alumina nanofluids have been continuously supplied to the cooling coil. The experiments have been performed under operation conditions include a variation of flow rate of chilled water/ alumina nanofluids and the air through the cooling coil. The experimental results have been shown a less time is achieved to obtain the desired child fluid temperature for all the different concentrations of nanofluids (Al2O3- water) compared with pure water. Also, the results revealed an increasing in the COP by about 5%, and17% for alumina nanoparticles concentration 0.1, and1% by weight respectively.