"密集洒水系统" can be translated as "intensive sprinkler system" or "dense sprinkler system" in English, depending on the specific context and intended emphasis.
"Intensive sprinkler system" emphasizes the high intensity or concentration of the watering, which might be suitable for areas requiring a significant amount of water in a short period or for specific watering needs.
"Dense sprinkler system" focuses more on the density or coverage of the sprinklers, implying a widespread or thorough watering effect.
In most cases, especially when referring to fire protection or irrigation systems, "intensive sprinkler system" is a commonly used and accurate translation.