The Englishman, third in this season's Formula 3 European Championship, will join the French squad, which carried McLaren-bound Kevin Magnussen to this year's title, at Aragon on Wednesday and Thursday.
Lynn already had half a day for free as a prize from Renault for his F3 performances, but has elected to drive for the full duration of the test.
But he played down speculation that, following his Macau win, he will move on from the category and into FR3.5.
"At the moment it's probably the thinking to stay in Formula 3," said Lynn, who is managed by ex-Formula 1 driver and current Toyota sportscar star Alexander Wurz.
"DAMS are a very good team and we want to have a link with them, if not for next year then for the future, and make the most of the opportunity.
"We'll discuss things in the near future, but I've still got strong links with HWA [Mercedes, which has backed his F3 career to date] and we've still got the same plan."
Lynn's 2014 campaign in F3 would again be with Prema Powerteam, the Italian team that carried him to European championship race wins and Macau victory this season.
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