Answer: The sentence provided is a compound-complex sentence.
Explanation: Compound-complex sentences are made up of two or more independent clauses and one dependent clause. Independent clauses can stand alone as sentences, while dependent clauses cannot stand by themselves because they do not express complete thoughts. In the sentence provided, the two independent clauses are "I know the man" and "He doesn't know who I am" and the dependent clause is "although I've tried to introduce myself several times". Moreover, the two independent clauses have been joined by means of the coordinating conjunction "but" and the dependent clause has been introduced by the subordinating conjunction "although".
