Water cooler radiator with unusual air flow direction

Hi everyone!

I'm doing a DIY project in which I have to use air cooling to regulate water temperatures of max 90°C. I want to use some cheap (possibly even used) pre-manufactured radiator to do the job for me (since I'm unable to make finned pipes with tight enough fittings to provide sufficient heat conduction between the tube and sheets), but I have environment constraints that make it impossible to channel the air through the largest surface like automotive radiators do (pic 1). I have to direct air through the 'side surface' (pic 2). I simply need long parallel aluminum sheets with tubes going through them. The dimensions of the radiator are planned to be roughly 50x500x700mm and the inner diameter of the tube should be ~10mm. I have been searching through the internet for days, but I'm not happy with my results. The best match at the moment is some oil cooler radiator which I find unnecessarily high in quality for my application (pic 3).
How can I find a radiator that is suitable for this? In what field do they use such radiators?

You could use a 25 mm thick heat exchanger and mount it at an angle similar to the heat exchanger I built for heating my shop as shown in the photo below. The photo does not show the spreader vanes inside the transition piece between the blower and the heat exchanger plenum. Look for automotive heat exchangers - radiators, air conditioner condenser heat exchangers, oil coolers, or possibly heater cores.

Welcome to PF.

Consider a bare 10 mm tube, without fins, folded back and forth across the airflow many times. Place the tube in a zig-zag-ing across the airflow, from the outlet of the air to the inlet, as a counterflow heat exchanger.

Now consider doing the same with finned tube, designed for use as a heat exchanger in an air compressor or a refrigerator. If the bend radius is too tight, use separate 180° elbows on either side.

It could be bent from a single tube, as a two layer structure, like a helix, flattened, skewed and staggered, to fit in the rectangular box.

Welcome, @pozsar !

I hope that you are aware of the air cooling effect being quickly reduced downstream.
What is moving the air?