EFFECT OF NOZZLE DIAMETER ON MICROSCOPIC AND MACROSCOPIC SPRAY CHARACTERISTICS OF SCR SYSTEM
Source abstract
Abstract
Spray and atomization are the keys to solving suboptimal performance and solid deposit formation in compact selective catalytic reduction (SCR) system of methanol engines. However, the atomization characteristics under low-pressure SCR injection conditions remain insufficiently understood, particularly regarding the role of nozzle diameter. This study investigated the effect of the nozzle diameter on the macroscopic and microscopic spray characteristics of pure water under injection pressures of 0.5 and 0.9 MPa and ambient pressure of 0.1 MPa in a SCR injection system. The macroscopic results indicate that with higher injection pressure and smaller nozzle diameter, the spray becomes more dispersed, symmetrical, and stable, and the spray angle and spray area are increased. The microscopic results suggest that higher injection pressure and smaller nozzle diameter have a positive effect on the breakup of small droplets. This is confirmed by reduced Sauter mean diameter (SMD) of droplets and shifted towards smaller diameter of droplet size distribution. Interestingly, the smaller nozzle diameter is not sufficiently reliable. The spray area of D368 (nozzle diameter of 0.368 mm) was larger than that of D328 (nozzle diameter of 0.328 mm) was larger than that of D328 by 725 mm2 at 0.5 MPa and 655 mm2 at 0.9 MPa. The SMD of D368 was ~10 μm lower than that of D328. The meaningful conclusion is that the D368 injector is favorable to improvement of the spray and atomization parameters of SCR systems under high injection pressure.
Source: openalex_inverted_index · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Fluid Dynamics and Heat Transfer · Plant Surface Properties and Treatments · Electrohydrodynamics and Fluid Dynamics
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (47)
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