Previously. Inside refrigerator, I setup a single fan blowing directly against one chocolate mold. With inside temperature of 57 F and a directly blowing fan, the mold exhibited cracking and bending. Surely a result of too quick cooling.
Lowering fan speed might help overcome these problem but I’ll be needing one fan for each mold. I should think way to make a single fan blow air to two molds, with lower speed but the same volume on each.
This was the first. The fan inserted inside a rectangular tube with the other end sealed. I bore holes on tube sides. With this setup, the air forces to exit to perpendicular holes, increasing the air flow coverage greatly.
Not good. The hole farthest from the fan exhibited the strongest speed while the nearest hole was very week.
I thought of mounting the fan on servo motor. Constant fan swivel is sure nice. However, this entails additional electronic work and cost. And, base from experience, affordable hobby servo are not reliable.
I tried mounting two cardboard deflector on fan. The idea was similar to shopping mall ceiling mounted blowers. On blower end are series of concentric angled frame to diffuse air flow.
It was a stupid idea. The fan was already designed to blow air outwards.
Then, I redesigned the previously made rectangular tube. The fan blowing on middle and air outlet on both ends, again, perpendicular to air flow. This got better air coverage, slower air current and of almost equal strength on both outlet. Going to setup two of this next time inside refrigerator.