How do simile and metaphor differ in their approaches to creating experience for a reader?

A metaphor can be used to replace one idea with another.  For example, a tsunami can be described as a "wave of destruction" for the damage that it causes.  It implies a comparison.  A simile establishes the comparison of ideas.  An endless torrent of rain flooded the valley like a tsunami.

Pardon me. to answer questions like this, we would have needed more information. for starters, two sentences from the excerpt that came with the question.