Solar steam generation has become one of the most promising techniques to realize water purification and desalination owing to the abundance and cleanness of solar energy. Here, we proposed a preheating chamber structure for high-efficiency solar steam generation with carbonized sawdust beds as the solar absorber. Effects of bed porosity on the water transportation, heat transfer and evaporation performance were studied. Experimental results turn out that with the increase of the bed porosity, the heat conductive loss will be increased while water transportation is promoted. When the positive effect of the increased water transportation and the negative effect of the increased heat losses on the evaporation are balanced, the evaporation efficiency reaches the maximum of about 91.5% at the porosity of 76% under one sun illumination in this work. In addition, the influence of water supply on the steam temperature under 3-sun irradiation was also investigated. It turns out that the evaporation efficiency and temperature can be coordinated by adjusting the water-supply area. When the ratio of water-supply area to the evaporation area reaches 58.8%, a proper balance between efficiency (33.8%) and steam temperature (115.8 °C) can be achieved. This work is expected to supply a method to obtain high temperature and also efficiency steam generation.

由于太阳能的丰富和清洁，太阳能蒸汽发电已成为实现水净化和海水淡化的最有前途的技术之一。在这里，我们提出了一种以碳化锯末床作为太阳能吸收器的高效太阳能蒸汽产生预热室结构。研究了床层孔隙度对水输送、传热和蒸发性能的影响。实验结果表明，随着床层孔隙度的增加，在促进输水的同时，导热损失也会增加。当平衡增加输水量的积极影响和增加的热量损失对蒸发的消极影响时，该工作在一次阳光照射下在孔隙率为76%的情况下蒸发效率达到最大值约91.5%。此外，还研究了供水对3-sun辐照下蒸汽温度的影响。结果表明，通过调整供水面积，可以协调蒸发效率和温度。当给水面积与蒸发面积之比达到58.8%时，可实现效率（33.8%）和蒸汽温度（115.8℃）的适当平衡。这项工作有望提供一种获得高温和高效蒸汽产生的方法。8%) 和蒸汽温度 (115.8 °C) 可以达到。这项工作有望提供一种获得高温和高效蒸汽产生的方法。8%) 和蒸汽温度 (115.8 °C) 可以达到。这项工作有望提供一种获得高温和高效蒸汽产生的方法。