| Thermal barrier coating technology employed a ceramic insulating layer, characterized by low thermal conductivity, to safeguard diesel engine piston bases. With the evolution of engines towards higher power outputs, there has been a corresponding increase in operating temperatures within combustion chambers. However, the prevalent insulating material, 8% yttria-stabilized zirconia (YSZ), exhibits susceptibility to phase transformation and sintering under high-temperature conditions. Consequently, the research spot-light has shifted to ceramic layer materials that boast high thermal stability and robust thermal properties. This study delves into gadolinium zirconate (Gd2Zr2O7, GZO) as the insulating ceramic layer, constructing a finite element model for a dual-layer thermal barrier coating. The temperature values of 11 simplified measurement points on an uncoated piston under test conditions were measured using the hardness plug temperature measurement method and compared with simulation results. The error verified the accuracy of the piston's finite element model. Based on this verification, numerical simulations were conducted on die-sel engine pistons coated with varying thicknesses of GZO (0.1mm, 0.2mm, 0.3mm, 0.4mm). The results indicate that TBC pistons can significantly reduce the temperature of the piston base, with a temperature reduction of 13.3°C to 45.01°C, the highest decrease being approximately 11.92%. As the thickness of the ceramic layer increases, the temperature of the piston substrate decreases, and the temperature of the piston top surface increases. For every 0.1mm increase in the ceramic layer, the temperature of the piston body decreases by 10-14 ℃. This has good guiding significance for the spray design of the new GZO coated piston. |
