ABSTRACT:
Dense slurries are often produced and transported in mining engineering. Handling such high-volume fraction particulate flows often results in high pressure drop and severe erosion damage in facilities. Underestimating the erosion damage may result in catastrophic health, safety and environmental problems. The present study aims at modeling erosion in dense slurries by using computational fluid dynamics simulation. We use dense discrete particle model which takes into account both particle-fluid and particle-particle interactions. Numerical modeling is first conducted for a slurry impingement test with available experimental data through which the accuracy of the model is validated. Then, CFD simulation is conducted for a flow loop transmitting slurry flow. A comparison of the obtained CFD results with measured erosion rate (R=96.05%, mean percentage error=11.24%) indicates a great potential of DDPM for modeling erosion in dense slurries.
INTRODUCTION
Dense slurries are encountered in several industrial sectors such as mining and petroleum engineering. High volume fraction of particles in such flow systems results in several issues such as high pressure drop, particle deposition and erosion, to name a few. Fluid handling facilities in such systems suffer from severe wear and underestimating the damage from erosion may result in catastrophic health, safety and environmental problems. Hence, the capability of predicting erosion damage in a quantitative manner is of paramount importance for designing such systems.
Due to the importance of erosion in different industrial sectors, several studies were carried out to identify the influential factors affecting the severity of erosion. Besides, several models have been proposed to quantify the erosion damage (Arabnejad et al., 2015; Finnie, 1960; Oka et al., 2005; Zhang, 2006). Such erosion models are often used along with computational fluid dynamics (CFD) models to precisely predict the trajectory of particles and the erosion damage due to the interaction of particles and walls.
Thus far, several researchers used CFD models to investigate the flow-field and erosion in different geometrical conditions (Chen et al., 2006; Darihaki et al., 2017; Pouraria et al., 2017). However, numerical modeling of erosion in dense slurries has been scarce. Furthermore, erosion prediction is often conducted using discrete particle model (DPM) in which the inter-particle collisions are totally neglected. Due to the low particle loading in most of processing systems such an assumption is generally valid. However, as the particle loading increases, the influence of suspended particles on the motion of carrier fluid and the inter-particle collisions becomes more important. In such cases, simplified models such as DPM cannot predict the flow fields. Hence, using more sophisticated methods are essential.