Jerusalem Beach is located across from the Opera House on the Tel Aviv-Yafo boardwalk. Due to its location, crowds are always located there including tourists and locals respectively, and at all times of day.
If you are looking for intimacy, it would be hard to find it therein.
Those interested in kite surfing, on the other hand, can practice the extreme sport on the southern end of the beach, known as Geula Beach.
Photos by Avishai Teiche, from PikiWiki website.