This study investigates the effect changing the PH of a copper nanofluid and sodium dodecylbenzenesulfonate (SDBS) surfactant concentration has on the thermal conductivity of the nanofluid. The thermal conductivity was determined through the Hot Disk Transient Plane (TPS) method. As the PH is increased the thermal conductivity also increases because higher PH means more surface charges which increase conductivity. As the SDBS concentration is increased the thermal conductivity slightly increases ...