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This paper details and develops novel wing shape hydrocarbon fuel cooling channel for enhancing the heat transfer capability of hypersonic vehicle electricity supply blades under rotating conditions. The effect of parameters such as wing base position and height on the thermal performance in the rotating situation is studied. The calculation results show that the wing base height H = 0.6D-0.8D wing shape channels have generally higher thermal performance and generally lower friction coefficient. Thermal performance of the channel with wing base parameters L = 10 D, H = 0.6 D is maximally increased by 350.2 % and friction coefficient is maximally reduced by 98.5 % compared with the straight channel at inlet temperature of 590 K and rotational speed of 35,000 rpm. As the wing base position L increases, both the thermal performance and the friction coefficient increase and then decrease under the influence of the pressure difference. Under the condition of high rotational speed, the wing base height H = 0.8 D and H = 0.6 D wing shape channels will obtain the maximum value of thermal performance in the range of L = 2 D-4 D and L = 6 D-10 D of the wing base position, respectively.

This paper examines the impact of a polyvinylidene fluoride (PVDF) and carbon nanotube (CNT) hybrid coating on the heat transfer and hydraulic performance of serpentine microchannel heat sinks. In an aluminum serpentine microchannel heat sink using deionized water as the working fluid, the heat transfer performance and flow resistance were analyzed for different mass fluxes (G) in both PVDF-CNT coated (PSMC) and uncoated (TSMC) heat sinks under different heat flow densities. The results demonstrate that the PVDF-CNT coating enhances the heat transfer and hydraulic performance of the serpentine flow channel. Compared to the TSMC, the convective heat transfer coefficient of the PSMC increased by up to 61.9%, while the flow resistance coefficient decreased by up to 33.8%. The PVDF-CNT coating offers a superior balance of heat transfer performance and pressure drop compared to the addition of fins. A critical interval for the inlet mass flux G was identified, beyond which the heat transfer efficiency improvement of PSMC over TSMC was more pronounced.

In this paper, the flow and heat dissipation performance of 0.1–0.5 vol per cent of Al2O3 -water nanofluid through serpentine micro-channel was experimentally studied in the Reynolds range 124–1000. By analyzing the experimental results of nanofluid flow and heat dissipation: In the experiment, the Nusselt number of nanofluids is 1.12–1.66 times that of deionized water, which indicates that Al2O3 -water nanofluids have significant heat transfer enhancement effect. Nanofluid flow resistance is 1.02–1.80 times that of deionized water, this indicates that Al2O3 -water nanofluid has the disadvantage of increasing energy consumption. From a comprehensive performance point of view: all the nanofluids used in the experiment have enhanced heat transfer factors more significant than one, and the enhanced heat transfer effect is better than that of deionized water, this suggests that Al2O3 -water nanofluid has the drawback of rising energy consumption. All the nanofluids used in the experiment have enhanced heat transfer factors more significant than one, and the enhanced heat transfer effect is better than that of deionized water. Nano-fluids, with a volume fraction of 0.4%, have an average increased heat transfer factor of 1.4, which is the best overall performance.