Addressing a letter to a consulate?

Question

is it necessary to put a name on it, or is just the address ok?

Answer 1

Place the name of the consul in order that the letter will be entertained with enthusiasm.

Answer 2

The more information you can put on the outside of the envelope, the sooner it can be delivered to the proper person.  At the very least, put the proper department (for example, Non Immigrant Visa Section) on the address.