Fabrication and Characterization of Carbon-Based Nanofluids through the Water Vortex Trap Method

Table 2

Basic physicochemical characteristics of the CBNFs.

Item	Experimental data					CR (%)
	(°C)	Water	V2-5	V3-5	V4-0	V2-5	V3-5	V4-0
Mean particle size (, nm)	25	—	749.56	692.05	269.90	—
Zeta potential (, mV)	25		−12.86	−13.98	−29.80
Density; (, kg/m^3)	30	996.27	996.07	996.43	996.17	−0.02	0.02	−0.01
	40	991.87	992.97	993.00	992.70	0.11	0.11	0.08
	50	987.33	987.70	988.70	987.60	0.04	0.14	0.03
pH	30	8.00	7.29	7.06	7.17	−8.83	−11.75	−10.42
	40	7.62	7.37	7.01	7.25	−3.32	−8.05	−4.90
	50	7.56	7.38	7.26	7.33	−2.38	−3.97	−3.04
Electrical conductivity; (, μS/cm)	30	110.70	257.00	280.50	190.50	132.16	153.39	72.09
	40	113.70	261.67	285.17	193.32	130.14	150.81	70.02
	50	120.80	266.50	286.67	193.92	120.61	137.31	60.53
Viscosity; (, mPa s)	30	0.80	0.83	0.82	0.80	4.17	2.50	0.00
	40	0.72	0.78	0.75	0.75	9.30	4.65	4.65
	50	0.65	0.70	0.73	0.65	7.69	12.82	0.70
Specific heat; (, kJ/kg °C)	30	4.183	4.082	4.165	4.197	−2.40	−0.42	0.34
	40	4.182	4.083	4.172	4.196	−2.36	−0.24	0.33
	50	4.182	4.091	4.175	4.191	−2.17	−0.17	0.22
Thermal conductivity; (, W/m K)	30	0.618	0.615	0.623	0.622	−0.44	0.87	0.73
	40	0.629	0.643	0.633	0.638	2.21	0.56	1.29
	50	0.644	0.658	0.654	0.652	2.26	1.63	1.29