The convective heat transfer coefficient of biologically produced
silver–ethylene–glycol/water nanofluid was experimentally quantified
in a counter-current double pipe heat exchanger.
Experimental results demonstrated that nanofluids can remarkably
enhance the heat transfer coefficient of heat exchanger comparing
to base fluid. In fact, biological nanofluid can change flow regime
earlier from laminar to transient, and transient to turbulent
regime. Addition of nanoparticles at volume fractions 0.1%, 0.5%