<p>This study investigates the effects of individual nanoparticle concentrations at a ternary nanofluid on flow and heat transfer characteristics under confined impingement jet conditions. The results shed light on the development of high-performance thermal management applications. The total nanoparticle concentration of the ternary nanofluid in the impingement jet formed by the circular nozzle was kept constant at 3%. Four cases were considered by varying the concentration of Al₂O₃, CuO, and SiO₂ nanoparticles in the total nanoparticle concentration between 0.5 and 2%. The study was carried out for dimensionless nozzle-to-plate distances of 1.1, 2.2, and 3.3, and Reynolds numbers of 9000, 15,000, 21,000, and 27,000. The results show that 0.5% Al₂O₃- 0.5% CuO-2% SiO₂/water ternary nanofluid increases the heat transfer than water and other ternary nanofluids, and it provides a 16.53% enhancement in heat transfer compared to water. It is also noticed that the concentration of nanoparticles and Reynolds numbers are generally more effective on average Nusselt numbers and pumping power than at nozzle-to-plate distances. Nevertheless, the stagnation Nusselt number change depends much more on the dimensionless nozzle-to-plate distance. A 15.24% rise in the stagnation point Nusselt number is noted as the <i>H/D</i> is increased from 1.1 to 3.3 at <i>Re</i> = 27,000. Furthermore, it is seen that after a certain Reynolds number, the entropy production due to friction becomes more dominant than the entropy production due to heat in the total entropy production.</p>