Study on the Mechanical Model of Slag and Quasi‐Static Analysis of Slag Samples in the Radiant Syngas Cooler

ABSTRACT In gasification processes, the accumulation of slag on the water tubes of radiant syngas coolers (RSCs) significantly impacts heat transfer efficiency and operational reliability. Understanding the mechanical properties of slag is crucial for optimizing slag removal strategies and enhancing system performance. This study aims to develop a comprehensive mechanical model of slag using the cohesive zone model (CZM) to simulate its brittle behavior under compressive loading conditions. By employing quasi‐static analysis in ABAQUS, we investigated the mechanical failure behavior of slag samples, focusing on crack initiation and propagation. Zero‐thickness cohesive elements were inserted into the model, and failure was assessed using the maximum nominal stress criterion. Experimental validation confirmed a relative error of 2.8% in compressive strength prediction and 4.3% in deformation. The simulation results revealed that initial damage accumulates within the slag sample before progressing to complete failure, characterized by significant aggregate detachment. To quantitatively assess the damage extent, a novel slag unit damage ratio (η t ) was introduced. It shows that 90% of elements are affected by pressure, but only 57% experience complete fracture (η t at SDEG > 0.9). This indicates the coexistence of fragmented and intact regions during failure. The CZM‐based approach demonstrated good agreement with experimental data, validating its effectiveness in predicting the mechanical behavior of slag under compressive loading. Our findings not only elucidate the entire process of mechanical fracture of slag but also provide a theoretical foundation for developing more effective slag removal strategies in RSCs.