The past standalone movies regarding Wolverine were named with titles containing the word "wolverine" but the recent movie is just named Logan.
Is there any particular reason behind keeping this name as the movie title?
There are a couple of reasons.
Firstly, the movie is loosely based on the Old Man Logan comic books series.
The basic concept of Old Man Logan—that of an aged Wolverine on a "buddy road trip" across America — was the inspiration for the 2017 Wolverine film Logan.
More importantly, perhaps, the movie is about the man, Logan, rather than the superhero, Wolverine, and how his era (and life) are coming to an end.
Additionally, it's implied that there will, perhaps, be a new Wolverine in future movies (as there is now in the comics where Logan is just Logan).
After the Death of Wolverine [comic run], X-23 took the mantle of Wolverine, but Old Man Logan was brought in to serve as an X-Man and featured in his own ongoing series.