It's easy to adjust (move the center pipe relative to the two fixed
pipes), has a lot of surface area (important so you don't get a hot
spot), and performs well with a small fan blowing along the axis of the
pipe.
If you're running more power (say >1 kW) then you might want to try some
other designs. multi gaps are popular, but have higher loss. Rotaries
work well, but are mechanically complex. A single blast gap can work
well, but you need an appropriate source of air (blower or compressor,
depending on the design)