If your account is closed, then the IRS will send you a paper check in the mail. It can take at least 8 weeks or more for the IRS to reissue the refund. Normally, the IRS also sends out a notice in the mail, if a direct deposit gets rejected by the bank. For more info about the notice, please see this IRS page: https://www.irs.gov/individuals/understanding-your-cp53a-notice
For more info, please see these IRS pages:
Please see this related TurboTax FAQ, What if I entered the wrong bank account for direct deposit?https://ttlc.intuit.com/replies/3302459
[Edited:02/27/2019]