Photoacoustic Method for Measurement of Thermal Effusivity of Fe₃O₄ Nanofluid

Figure 4

OPC signal amplitude as a function of modulation frequency for: (a) water, (b) EG, (c) blank (inside: log-log plot), and (d) Fe₃O₄ (inside: log-log plot) nanofluid.

(a)

(b)

(c)

(d)