Effects of solid particle aspect ratio on the performance of hydrogen production by electrolyzed water

Abstract

Hydrogen energy has become one of the important directions of future energy development. The hydrogen produced by electrolyzed water is regarded as "green hydrogen", is clean and pollution-free, and is considered the ultimate direction of hydrogen production. If the waste heat of solid particles can be used as the energy required for the water electrolysis process, the cost of "green hydrogen" will be much lower than that of fossil fuel hydrogen production. In order to study the effect of particle structure size on hydrogen production capacity, the heat transfer model of the ellipsoidal particles packed bed with single-vacancy was constructed. Further, the temperature, the apparent thermal resistance, the average heat flux, and the vacancy affects area were studied. With the increase of the particle aspect ratio, the apparent thermal resistance decreases, the average heat flux increase, and hydrogen production increases. When the particle aspect ratio increases from 0.5 to 2.0, the average heat flux of the packed bed with single-vacancy increases from 23.13 kW/m2 to 28.87 kW/m2, and the apparent thermal resistance decreases from 23.33 K/W to 9.27 K/W. As the particle aspect ratio increases, the area affected by single-vacancy increases, the hindering effect of the vacancy on the heat flow increases.