Volume 48, No 3, 2026, Pages 437-455
Download full text in PDFMultiobjective Optimization of CuO Nanolubricated Three-Lobe Journal Bearings Using Taguchi-GRA and TOPSIS Methods
Authors:
Suman Kumar Mandal 
,
Biplab Bhattacharjee ,
Nabarun Biswas ,
Kishan Choudhuri ,
Prasun Chakraborti
DOI: 10.24874/ti.1970.06.25.10
Received: 26 June 2025
Revised: 5 September 2025
Accepted: 18 October 2025
Published: 15 September 2026
Abstract:
Three-lobe journal bearings are frequently used in high-speed rotating machinery due to their superior stability and load-carrying capacity over plain bearings. However, due to conflicting objectives like maximising peak pressure and minimising frictional torque, optimising their performance under nanolubricated conditions is still difficult. This study investigates the impact of copper-oxide (CuO) nanolubricants on the functionality of a three-lobe journal bearing is examined experimentally. Rotational speed (1000–2000 rpm), load (150–450 N), and nanoparticle concentration (0.05–0.10 wt.%) are all varied using a Taguchi L9 orthogonal array. For multiobjective optimisation, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Grey Relational Analysis (GRA) were combined. The results of the analysis of variance showed that load is the main contributing factor (>94%). The optimal parameters determined by both GRA and TOPSIS are 1000 rpm, 450 N, 0.1% wt. concentration of CuO, which is then validated experimentally showing less than 5% error. Hence, the findings support a novel dual-optimization strategy for better bearing performance by confirming that CuO nanolubricants dramatically increase hydrodynamic pressure and decrease frictional torque.
Keywords:
Three-lobe bearings, CuO nanoparticles, Peak pressure, Frictional torque, GRA, TOPSIS
