As an efficient heat transfer enhancement element, 3-D finned tube has good potential in the field of waste heat utilization of industrial flue gas. However, the industrial flue gas often contains a large amount of ash particles. Meanwhile, ash deposition on the surface of heat exchanger can worsen the heat transfer performance and even shorten the service life of the heat exchanger. Therefore, the research of coupling effect of heat transfer and ash deposition on 3-D finned tube heat exchanger is very necessary, and it is bound to affect the further promotion and application of 3-D finned tube heat exchanger. In this paper, the influence of ash deposition on heat transfer process of 3-D finned tube heat exchanger was further studied. The effects of ash deposition time on heat transfer rate and relative pressure drop were discussed firstly. It was found that both ofheat transfer and relative pressure drop basically tended to be stable with the running time up to 6 hours. Then, the influences of fin height of 3-D finned tube, gas velocity and particle concentration on fouling characteristics, heat transfer and flow performance were studied according to the orthogonal array design method. The optimized parameters corresponding to the smallest fouling coefficient and the least relative pressure drop after fouling were determined. Besides, the performance of 3-D finned tube heat exchanger with the optimized parameters was also compared with other tested heat exchangers. The results showed that the heat exchanger with optimized parameters had better heat transfer performance than the other cases under the same condition. At last, a correlation of fouling coefficient of 3-D finned tube heat exchanger under the optimized parameters with ash deposition time was obtained, and it can be useful in the design and evaluation of heat exchanger in dusty environment.

3-D翅片管作为一种有效的传热增强元件，在工业烟气余热利用领域具有良好的潜力。但是，工业烟道气通常包含大量的灰烬颗粒。同时，灰分沉积在热交换器的表面上会恶化传热性能，甚至缩短热交换器的使用寿命。因此，研究3-D翅片管换热器传热与灰分耦合的耦合效应十分必要，必将影响3-D翅片管换热器的进一步推广和应用。本文进一步研究了灰分沉积对3-D翅片管式换热器传热过程的影响。首先讨论了灰分沉积时间对传热速率和相对压降的影响。发现在运行时间长达6小时的情况下，传热和相对压降都基本趋于稳定。然后，根据正交阵列设计方法，研究了3-D翅片管翅片高度，气体速度和颗粒浓度对结垢特性，传热和流动性能的影响。确定对应于最小结垢系数和最小结垢后相对压降的优化参数。此外，还对具有优化参数的3D翅片管式换热器的性能与其他经过测试的换热器进行了比较。结果表明，在相同条件下，参数优化的换热器的传热性能优于其他情况。终于，