What i have done to control temp and pellet consumption on my
rocket stove. Cool accidental effect with this is the tube heats up and starts gasification of the pellets before they are burnt which causes a pretty cool blue flame and lots of heat. A simple brick makes a easy lid and keeps 99% of smoke in, sometime if the brick is not good
enough air will get drawn down the tube allowing the "
wood Gas" to be ignited and it will burp out a flame lol. Also have noted allowing too much air around pellet feeder will allow smoke back only up the pellet tube, not anywhere else.