Upvote:2
I would strongly recommend getting a regular multiple-entry Singapore visa.
The Visa-Free Transit Facility (VFTF) is intended for people who are connecting in Singapore on their way somewhere else. Various online sites claim that a single ticket is required, but technically, the ICA only mandates an onward ticket. However, you will need to convince not just the ICA, but the check-in agent for your Chennai-Singapore-Chennai flights, who will only see a return ticket that absolutely does require a visa. What's more, you will need to do this twice, since when returning from Victoria, Singapore will appear to be your final destination. Getting a visa will make this much, much smoother.