GUO Yinga ，ZHANG Yilanb ，WANG Jianjunb ，XU Weiweib ，CHANG Yuanjianga ，LIU Yangb
a. College of Mechanical and Electronic Engineering， b. College of New Energy，
China University of Petroleum （East China）， Qingdao 266580， China
Abstract
Objective In the modern petroleum refining industry， the flue gas turbine serves as a critical component in catalytic cracking units. However， ultrafine particles，smaller than 10 μm，that are not captured by the third-stage cyclone，tend to deposit on the surfaces of turbine blades. This leads to rotor dynamic imbalance and excessive shaft vibration， thereby compromising operational safety and significantly reducing both the energy recovery efficiency and economic performance of the unit. Therefore， it is crucial to investigate the gas-solid two-phase flow field within the flue gas turbine，as well as the dynamic behavior and deposition characteristics of particles on blade surfaces.
Methods The experiments were conducted in combination with numerical simulations. A cold-state laboratory model was employed to study particle deposition.High-viscosity talc powder was used to simulate the deposition characteristics of industrial gas turbine particles under high-temperature， low-concentration， and long-duration conditions by replicating a high-concentrati-on， short-duration gas-solid two-phase flow. A single-blade flow-around deposition device was constructed based on the actual structure of the gas turbine impeller. Experimental parameters，including inlet flow rate， inlet particle concentration， and blade surface roughness，were varied to analyze their effects on particle deposition behavior. Numerical simulations were conducted using Fluent software， employing the RNG k-ε turbulence model and the discrete phase model （DPM）. A critical stress model， implemented through a user-defined function （UDF）， was coupled with a rolling detachment model to simulate the gas-solid two-phase flow field and the dynamic deposition process.
Results and Discussion Using the single-blade flow-around deposition experimental device， the effects of blade surface roughness， inlet flow rate， and inlet particle concentration on particle deposition characteristics were investigated. When the blade surface roughness was varied， the deposition patterns on the pressure and suction sides remained largely unchanged under the given experimental conditions. Regarding deposition mass， the pressure side showed minimal variation with increasing roughness， while the suction side exhibited a slight decreasing trend. The particle size distribution of the deposited particles was largely unaffected by surface roughness. When the inlet flow rate increased， the deposition-free area on the edge of the pressure side expanded，while particle detachment decreased. On the suction side， the deposition area remained nearly unchanged，with a significantly smaller deposition thickness than that on the pressure side. Asthe inlet particle concentration increased， the deposition mass on the pressure side gradually increased， while that on the suction side first decreased and then increased. Numerical simulations were used to obtain the gas-phase flow field and particle trajectories. By setting the inlet flow rates to1 200 m3/h and 1 600 m3/h， the distributions of particle deposition and detachment mass were obtained， showing good agreement with the experimental results. Additionally， the effect of wall material on particle deposition was assessed. For the same particles， deposition onto an existing particle layerled to reduced detachment and enhanced particle deposition.
Conclusion Surface roughness primarily affects the formation of the initial deposition layer， while the subsequent deposition process is dominated by the particle layer. An increase in inlet particle concentration results in increased deposition mass on both the pressure and suction sides. The inlet flow rate exerts a dual effect on particle deposition： increased particle velocity and contact stress promote deposition， whereas enhanced airflow shear stress intensifies particle detachment. Once the particle layer is established， it reduces detachment difficulty and promotes further deposition.
Keywords： ultrafine particle； particle deposition； flue gas turbine
Get Citation:GUO Ying， ZHANG Yilan， WANG Jianjun， et al. Experiments and numerical simulationson deposition characteristics of ultrafine particles on gas turbine blade surfaces［J］. China Powder Science and Technology， 2026， 32（3）： 1-14.
Received: 2025-03-31 .Revised: 2025-06-30,Online: 2025-09-08.
Funding Project: 国家自然科学基金项目，编号：52476043。
First Author:郭颖（1976—），女，讲师，博士生，研究方向为安全工程及机械设计、多相流动与分离技术。E-mail：Guoying1976@upc.edu.cn。
Corresponding Author:王建军（1971—），男，副教授，博士，硕士生导师，研究方向为气固-气液、多相流动过程及旋流分离技术。E-mail：wangjj01@upc.euc.cn。
DOI：10.13732/j.issn.1008-5548.2026.03.001
CLC No:TB4； TQ324.8 Type Code: A
Serial No:1008-5548（2026）03-0001-14
