Airport Dortmund
To reach the Dortmund University of Technology starting at Dortmund Airport it´s advisible to take "The Airport Express", which carrys you directly to the train station "Dortmund Hbf". From there you can reach the university with S-Bahn transit S1.
At Düsseldorf Airport you can continue your journey on the train station "Düsseldorf Flughafen". From there trains depart to train station "Dortmund Hbf" regularly. Information for the further journey from "Dortmund Hbf" toward the University of Dortmund is to be found under public Transport.