Ultimaker 2 Airflow Optimized Cooler for Olsson Block

Aim: Design a 3D printable cooling air flow guide for the Ultimaker 2 with a Olsson hotend.

I was inspired by other designs and started to analyze them in regard of mechanics and airflow. All designs known to me were very hard to print or lacked an airflow guidance. So I decided to optimize both issues.

This is designed to be printed with a 0.4mm nozzle with a layer height of 0.1mm.
15-20% Infill, 2 perimeters, 0.5mm of layers for the bottom (1*0.2mm and 3*0.1mm), 5 top layers depending o