End effects in acoustic pipes
The work of a curious fellow


When air vibrated in a closed end pipe, there is actually some air particles vibrating at the opening of the pipe. So for the fundamental pattern, the wave inside the pipe is not equal to 1/4 lambda. It is described as 'end correction' in our textbook and the actual length inside the pipe is less than 1/4 lambda. How can we minimize this effect?


To minimize the end effects, and edge effects, which occur in organ pipes, capacitors, induction coils etc. make the object so that the end or edge is minimized relative to the whole structure. If you have an opportunity to look at a pipe organ, perhaps in a nearby church, notice that the shorter pipes are made thinner also, so that the end area remains small compared to the length.