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A feasible and cost-effective method was developed to improve the photoelectrochemical performance of hematite (α-Fe2O3) photoanode. Using a hydrothermal method, tin (Sn) and magnesium (Mg) (co-)doped hematite films were prepared...

The heat transfer process of the inclination round jet impingement is studied experimentally for improving the cooling capacity and uniformity of the ultrafast cooling used in Thermo-mechanical Control Process. The heat transfer characteristic is presented for jet inclination angle from 0 to 60 . The video images of heat transfer process and heat flux curves demonstrate that the wetted region extends asynchronously due to the uneven water flow distribution. In the forward flow direction, the larger parallel flow velocity results to the fast wetting front propagation speed, and this is because the higher shear force under inclined condition is helpful to speed up the detachment of the bubbles on the surface. But in lateral and reverse directions, the situation is the opposite. The degree of asymmetry of the wetted region becomes remarkable, and at the same jet impingement cooling time, the wetted area increases at first and then shrinks with the increasing inclination angle. The larger jet velocity increases the maximum heat flux, and accelerates the wetting front propagation, especially in the parallel flow region. Thus, inclination jet impingement with the reasonable angle and jet velocity improves the heat transfer capability and plate surface cooling uniformity within the measurement region.

Thermo-mechanical control process (TMCP) technology is widely used for processing steels, where an important aspect is controlled cooling, Recently, the ultra-fast cooling (UFC) method, which has high flow speed, adjustable inclination angle, and stagger arranged nozzles is gradually replacing the traditional cooling practice. This paper focuses on the flow field and heat transfer mechanism in high temperature plates during the cooling process. Next, the effect of different initial temperatures (600 and 7508C) and inclination angles (08, 308, and 608) were studied. The surface temperature and heat flux were calculated using finite difference method. The data suggests that with the initial temperature increasing from 600 to 7008C, and the inclination angle increasing from 08 to 608, the maximum heat flux and its corresponding temperature increases in the major part of the cooling region. Given that the experimental conditions were similar to the industry, the new findings are expected to effectively guide the development of UFC in the near future.

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