This experimental study investigates the effects of TiO₂ nano-particles on the cooling and tribological performance of a vapor compression refrigeration system running on R134a as refrigerant and polyolester oil (POE) as lubricant. Dynamic light scattering analysis was conducted to observe the dispersion of the nano-particles. The heat transfer rate in the evaporator and condenser was taken into consideration to observe the cooling performance of the system charged with combination of 0.1 vol% and 0.5 vol% TiO₂ incorporated nano-refrigerants (R0.1 & R0.5) and 0.1 vol% and 0.5 vol% TiO₂ incorporated POE nano-lubricants (P0.1 & P0.5). Coefficient of friction and wear rate analyses were also performed on the piston ring of the compressor by immersing the samples in two different lubricants (P0.1 & P0.5). The compressor’s suction-discharge characteristics were assessed to determine the impact of the nano-fluid combinations. Scanning electron microscopy was used to examine the morphology of the nano-particles and worn surfaces. Atomic force microscopy was utilized to observe the structure of the worn substrates. The chemical composition of the worn surfaces was analyzed using energy-dispersive X-ray and the thermal stability of the nano-additives was ascertained via thermogravimetric analysis and differential scanning calorimeter. The best cooling and tribological performance results were obtained when the system was run on a combination of R0.5 + P0.1. Compared to standard conditions (R134a + POE), the highest increase in COP was 35.86% for R0.5 + P0.1. With the same combination, the cooling time was reduced by 22.25% and the highest decrease in the average coefficient of friction was 8.02% for 0.1 vol% of TiO₂ incorporated POE lubricant (P0.1).

_{本实验研究调查了 TiO 2}纳米颗粒对以 R134a 作为制冷剂、以多元醇酯油 (POE) 作为润滑剂运行的蒸汽压缩制冷系统的冷却和摩擦性能的影响。进行动态光散射分析以观察纳米颗粒的分散情况。考虑蒸发器和冷凝器中的传热速率，观察加入0.1 vol%和0.5 vol% TiO ₂纳米制冷剂（R0.1 & R0.5）和0.1 vol%纳米制冷剂组合的系统的冷却性能。 % 和 0.5 vol% TiO ₂掺入 POE 纳米润滑剂 (P0.1 和 P0.5)。通过将样品浸入两种不同的润滑剂（P0.1 和 P0.5）中，还对压缩机的活塞环进行了摩擦系数和磨损率分析。评估压缩机的吸入-排出特性以确定纳米流体组合的影响。使用扫描电子显微镜检查纳米颗粒和磨损表面的形态。利用原子力显微镜观察磨损基材的结构。使用能量色散 X 射线分析磨损表面的化学成分，并通过热重分析和差示扫描量热仪确定纳米添加剂的热稳定性。当系统在 R0.5 + P0.1 的组合上运行时，获得了最佳的冷却和摩擦性能结果。与标准条件（R134a + POE）相比，R0.5 + P0.1 的 COP 增幅最高为 35.86%。对于相同的组合，添加0.1vol%的TiO ₂ POE润滑剂时，冷却时间减少了22.25%，平均摩擦系数最大降低了8.02% （P0.1）。