R&D at KUBO

KUBO's Ultra Clima system has an Air Handling Unit (AHU) for each path in the greenhouse: a heating and cooling block with a fan that blows air through a long hose. Growers want to know how much air goes into the greenhouse (Q), because that tells them how quickly all the air gets replaced.

This was the biggest project of my internship. We set up one AHU with an 85 m hose and ran the fan at different speeds. Q can be calculated in a few ways, so we measured several things to compare them afterwards.

The measurements showed how the pressure is spread along the hose. With the results we could adjust the pattern of holes in the hose, so the air comes out more evenly along its length.

At a greenhouse near the coast in Portugal, the salty air made the aluminium corrode. The corrosion pushed on the glass until the panes broke. As a temporary fix, the frame around the glass was opened up a little with a special tool: you place it on the profile, tighten a bolt, and it pulls part of the profile up.

There was one tool, but three more were needed. The 3D models were lost and the people who made the original no longer worked there. At first I was only asked to get some quotes, but it turned into a redesign that I mostly did on my own.

For a project in Saudi Arabia, another department asked whether the PVC and aluminium parts would cause problems in that climate. In a brainstorm we named three risks: UV, high temperatures and thermal expansion.

Together with a colleague I looked at heat. We built a small setup with the PVC strips that hold the glass, put it in an oven at different temperatures, and checked flexibility and deformation afterwards. At high temperatures it lost strength and shape quickly. The conclusion of the whole research: standard PVC won't hold up in that climate, but a more UV-resistant type of PVC did fine.