Table 3 Properties of the nanofluid (at 25°C, 1 atm)
From: Spray cooling characteristics of nanofluids for electronic power devices
Ag | MCNT | |||||
|---|---|---|---|---|---|---|
Volume fraction, ϕ (vol.%) | 0.0025 | 0.0050 | 0.0075 | 0.0025 | 0.0050 | 0.0075 |
Density, ρ nf (kg/m3) | 997.24 | 997.47 | 997.71 | 997.04 | 997.08 | 997.12 |
Heat capacity, C p,nf (kJ/kg-K) | 4.19990 | 4.19980 | 4.19970 | 4.19991 | 4.19981 | 4.19972 |
Viscosity, μ nf (N-s/m2) | 8.90056 × 10−4 | 8.90111 × 10−4 | 8.90167 × 10−4 | 8.90028 × 10−4 | 8.900056 × 10−4 | 8.90083 × 10−4 |
Thermal conductivity, k nf (W/m-K) | 0.6060 | 0.6061 | 0.6062 | 0.6078 | 0.6095 | 0.6113 |
Prandtl number, Prnf | 6.16810 | 6.16788 | 6.16766 | 6.15041 | 6.13260 | 6.11490 |
Surface tension, σ(N/m) (measured) | 0.129 | 0.097 | 0.089 | 0.078 | 0.068 | 0.063 |
Surface area, (m2/100 g solution) | 3.9 | 7.8 | 11.7 | 1.3 | 2.6 | 3.9 |
Density, ρ nf | ρ nf = (1 − φ)ρ bf + φρ np [16] | |||||
Heat capacity, C p,nf | C p. nf = (1 − φ)C p,bf + φC p,np [17] | |||||
Viscosity, μ nf | μ nf = μ bf(1 + 1.25 φ) for MCNT [18] | |||||
μ nf = μ bf(1 + 2.5 φ) for Ag [19] | ||||||
Thermal conductivity, k nf | \( {k}_{\mathrm{nf}}={k}_{\mathrm{bf}}\frac{k_{\mathrm{np}}/{k}_{\mathrm{bf}}+K-K\upvarphi \left(1-{k}_{\mathrm{np}}/{k}_{\mathrm{bf}}\right)}{k_{\mathrm{np}}/{k}_{\mathrm{bf}}+K+\upvarphi \left(1-{k}_{\mathrm{np}}/{k}_{\mathrm{bf}}\right)} \) where \( K=2\ {\upvarphi}^{0.2}\left(\frac{1}{d}\right) \) for MCNT [20] \( {k}_{\mathrm{nf}}={k}_{\mathrm{bf}}\frac{k_{\mathrm{np}}+2{k}_{\mathrm{bf}}-2\upvarphi \left({k}_{\mathrm{bf}}-{k}_{\mathrm{np}}\right)}{k_{\mathrm{np}}+2{k}_{\mathrm{bf}}+\upvarphi \Big({k}_{\mathrm{bf}}-{k}_{\mathrm{np}\Big)}} \) for Ag [21] | |||||