Hi Debra
I assume you are referring to tax refund once you file your return. On page 2 of the 1040, you can enter the information regarding the bank / account you want your refund transferred to. If this is a £ account, it would be converted (on the exchange rate for the day) I assume.
If you do not enter this information on the 1040, they will send you a cheque to the address shown on page 1 of 1040.
I hope this answers your question
Helen