It depends on the facility and the officer handling the visit, and there is no consistent rule across all county jails.
In many county jails, when a visitor arrives and checks in, the corrections officer will contact the housing unit to let the inmate know they have a visitor. Whether that officer volunteers your name or waits for the inmate to ask varies. Some officers announce who is there as a matter of routine. Others simply tell the inmate they have a visitor and let the inmate decide whether to come out without knowing who it is. If he asks who is there, the officer will typically tell him.
So the honest answer is that he may find out it is you before he decides whether to come to visitation, particularly if he asks. Whether he would refuse to come out over an argument is something only you can read based on how things were left between you.
The original advice here is worth taking seriously. If the argument was significant enough that you are worried he might turn down the visit, a letter is the smarter first move. A letter gives him time to read your words privately, process them, and decide how he feels without the pressure of an immediate in-person decision. It is easier to refuse a visitor at the door than to ignore a letter that is already in your hands, and a warm letter that acknowledges the argument and extends some goodwill often opens a door that a surprise visit might not.
Write the letter first, smooth things over, and then plan the visit from a place of reconnection rather than uncertainty.