Bell, who come to the Eagles in the off-season as a restricted free agent, was traded after disappointing first five games, during which he gained only 28 yards on 16 carries.
Bell, a third-year pro out of the University of Arizona, spent the first two years of his career with the Denver Broncos.
Harrison, meanwhile, lost his Cleveland starting job this season to Peyton Hillis after carrying the ball 31 times for 91 yards. He compiled 1,401 yards rushing and six touchdowns in four-plus years with the Browns.
2014: The Year in Music [PHOTOS]