The key feature of these modes is that the velocity of the air in any of the modes must be zero at the closed ends of the tube. Ie, the ends of the tube must be modes for each of the velocity modes in the tube. The ends will in general not be pressure nodes, but will be places where the pressure has the largest oscillations.
Modes are smooth and the higher modes tend to have more nodes than the lower modes.
Away from the ends, the modes should have similarities with the modes in a double open pipe or a pipe with one end open. Ie, the velocity will have its largest deviations where the pressure has its nodes, and the pressure its largest deviations where the velocity has its nodes. Unless you are inside the pipe itself, the sound, being within a closed container, will not cause the air outside the tube to vibrate and thus will not produce any sound outside the tube. Here is a plot of the first three modes- both of the velocity and of the pressure. However the main effect would be to absorb the sound.