NOZZLE QUESTION??????

WHICH TYPE OF NOZZLE WORKS BEST FOR PORTS WHERE DO YOU WANT THE DISCHARGE IN THE CENTER OF THE PORT OR JUST INSIDE I HAVE SEEN LONG AND SHORT NOZZLES CHECK VALVE NOZZLES DROP IN JETS ETC WHICH ONES WORK THE BEST FOR A PORT SET UP.CAN'T SEEM TO FIND A ANSWER THANKS FOR THE SPACE