fan the flames vs irritate

fan the flames

verb
  • To intensify or worsen an already difficult situation. 

irritate

verb
  • To provoke impatience, anger, or displeasure in. 

  • To cause or induce displeasure or irritation. 

  • To induce pain in (all or part of a body or organism). 

How often have the words fan the flames and irritate occurred in a corpus of books? (source: Google Ngram Viewer )