My band director taught me that accents are like playing certain notes in forte for fortissimo (sp?). This works best for me, but try to blow your airstream much faster, but not as fast that the note will begin to break.
Ah. I tend to have to accent the 2nd octave notes often and when I do, I push the note up to the next octave. My strat. has always been to play the music surrounding the accent softer and hit the accent harder.
Does it help to think of the accented notes as marccato ("marked", detatched) instead of just louder? I usually teach accents more as articulation and style than louder vs. softer.