ABSTRACT

This research aims to experimentally investigate the thermal performance of iron oxide nanofluids having different particle shapes for multiple impinging jet flow. The heat transfer performance of nanofluids with spherical like, faced nanocube and nanowires shapes prepared by hydrothermal synthesis was investigated experimentally. The weight percentage of the nanofluids examined in this study is 0.2 wt%, and different jet-to-jet spacing (B) and jet-to-plate distance (H) values were tested for each nanofluid. The experiments were carried out for laminar flow conditions, the temperature distribution was obtained through thermocouples, and the Nu number was calculated for each case. In experiments using nanowires, it was observed that the highest Nu numbers were obtained for jet-target/diameter ratio 2 for all cases (jet spaces and Reynolds numbers). Maximum Nu number enhancement was approximately 27.3% compared to pure water for the specified conditions. This value is quite significant since it was obtained with a relatively low concentration of nanofluids. It was observed that the particle size and morphology shape significantly impact nanofluids’ performance in heat transfer.

摘要

本研究旨在通过实验研究具有不同颗粒形状的氧化铁纳米流体在多次冲击射流中的热性能。对水热合成制备的球形、面状纳米立方体和纳米线形状的纳米流体的传热性能进行了实验研究。本研究中检查的纳米流体的重量百分比为 0.2 wt%，并且对每种纳米流体测试了不同的喷射到喷射间距 (B) 和喷射到板距离 (H) 值。实验在层流条件下进行，通过热电偶获得温度分布，并计算每种情况的Nu数。在使用纳米线的实验中，观察到在所有情况下（射流空间和雷诺数），射流目标/直径比为 2 时获得最高的 Nu 数。在指定条件下，与纯水相比，最大 Nu 数增强约为 27.3%。该值非常重要，因为它是用相对较低浓度的纳米流体获得的。据观察，颗粒尺寸和形态形状显着影响纳米流体的传热性能。