Purpose

During the past several years, research and studies in the field of solar energy have been continuously increased. One of the substantial applications of solar energy is related to industrial utilization for the drying process by efficient heat transfer methods. This study aims to upgrade the overall performance of an indirect solar dryer using a solar absorber extension tube (SET) equipped with ball-type turbulators.

Design/methodology/approach

In this work, three various SETs including hollow (SET Type 1), 6-balls (SET Type 2) and 10-balls (SET Type 3), have been simulated using Fluent software to evaluate heat transfer characteristics and flow structure along the air passage. Then, the modified solar drying system has been manufactured and tested at different configurations.

Findings

The findings indicated that adding a SET improved the performance notably. According to the results, using turbulators in the tube has a positive effect on heat transfer. The highest overall thermal efficiency was found in the range of 51.47%–64.71% for the system with SET Type 3. The maximum efficiency increment of the system was found as 19% with the use of SET. Also, the average specific moisture extraction rate, which is a significant factor to survey the effectiveness of the dehumidification system was found between 0.20 and 0.38 kg kWh⁻¹.

Originality/value

In the present study, a novel SET has been developed to upgrade the performance of the solar dehumidifier. This new approach makes it possible to improve both thermal and drying performances.

中文翻译：

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用于提升太阳能干燥器性能的带有湍流器的太阳能吸收器延长管的数值和实验研究

目的

在过去的几年中，太阳能领域的研究和研究不断增加。太阳能的重要应用之一与通过有效传热方法进行干燥过程的工业利用有关。本研究旨在使用配备球型湍流器的太阳能吸收器延长管 (SET) 来提升间接太阳能干燥器的整体性能。

设计/方法/方法

在这项工作中，使用 Fluent 软件模拟了三种不同的 SET，包括空心（SET 类型 1）、6 球（SET 类型 2）和 10 球（SET 类型 3），以评估沿空气的传热特性和流动结构通道。然后，改进的太阳能干燥系统已经制造并在不同的配置下进行了测试。

发现

研究结果表明，添加 SET 显着提高了性能。根据结果​​，在管中使用湍流器对传热有积极影响。使用 SET 类型 3 的系统的最高总热效率在 51.47%–64.71% 的范围内。使用 SET 的系统的最大效率增量为 19%。此外，作为调查除湿系统有效性的重要因素的平均比水分提取率在 0.20 和 0.38 kg kWh ^-1之间。

原创性/价值

在本研究中，开发了一种新型 SET 来提升太阳能除湿机的性能。这种新方法可以提高热性能和干燥性能。