Multi-factor impact mechanism of the hydrothermal performance of manifold microchannel heat sinks based on multi-method collaborative optimization

Manifold microchannel heat sink(MMCHS) is an effective cooling technology, which can dissipate high heat flux of electronic devices quickly. In this study, the orthogonal experimental design(OED) and grey relational analysis(GRA) methods were used to investigate the effects of five geometric parameters(width of the wall, depth of the channel, height of the manifold, length of the manifold inlet and length of the manifold outlet) on the thermal resistance and pump power of MMCHS. The results of the grey relational analysis show that the width of the wall and the length of the manifold inlet have the most significant influence on the thermal resistance and pump power. Subsequently, decision-making methods such as TOPSIS and LINMAP were used to calculate the optimal solutions from the data set generated by the genetic algorithm. Based on the LINMAP decision-making results, an MMCHS structure with equilateral triangle ribs was proposed, and the performance of this structure at different volume flow rates was numerically simulated. The performances of MMCHS with different numbers of ribs in terms of pressure drop, temperature, performance evaluation criterion(PEC), and performance evaluation criterion based on thermal resistance(PECTR_Tmax) were extensively investigated. The results show that when the volume flow rate is 0.06 ml/s, the optimal structure MM-TR exhibits excellent performance, with a PEC of 1.28 and a PECTRTmax of 1.21. Compared with other MMCHS, the MM-TR proposed in this study is a more energy-efficient electronic cooling solution. Under a heat flux of 988 W/cm², the coefficient of performance(COP) of MM-TR can reach above 30,240.