According to a circular from Press Information Bureau, Ministry of Defence, Govt. of India, members of the public (Indian citizens above 5 years of age) will be permitted to visit Indian Naval Ships on Apr. 13 (Friday) & Apr. 15 (Sunday), 2018 on the occasion of #DefExpo2018. Time: 8 A.M. to 5 P.M. on both the days.
People who wish to visit the Indian Naval Ships are requested to go to Island Exhibition Grounds venue (Google Maps link for location) from where Indian Navy will arrange shuttle bus services to and from Chennai Port Trust, where the ships are located. Visitors are not permitted to go directly to Chennai Port Trust – they should come only to Island Grounds, according to the announcement.
An original Govt. issued Photo ID is required for everyone who wish to go. I guess there are no ticket charges for this visit – nothing is mentioned in the circular through. Also, cameras, photography, and any hand baggage is prohibited.
Further Information: Refer to this Circular.
On a related note, members of the public will be allowed to visit the Defence Expo 2018 (#DefExpo2018) on Apr. 14 (Sunday) only. Timing: 9 A.M. to 5 P.M. There is no entry fee (the previously announced Rs. 100 entry ticket has been waived off) but you need to carry a Valid Govt. Issued Photo ID.
Defense Expo Location: Land of Arulmigu Nithyakalyana Perumal Temple, adjacent to Vadanemmeli Sagaya Matha Church, Thiruvidanthai, Thiruporur Taluk, Kancheepuram, East Coast Road, Chennai, Tamil Nadu, India. (Google Maps link for location)