messing with /increasing evap airflow?

[knighty]

I'm using freezer truck containers with added refrigeration as blast freezers... space/availability/price makes them great for the job. (not using the truck systems)

frozen dog food, in at ambient temp, needs to be frozen to -18'C - current systems are set to -35'C to try and make sure meat is frozen through - only make it to -35'C after the weekend when no product added

I'm moving things around and getting 8 more containers, with a new way to fill them, so I can stack the evaporators ontop of each other at the far end (away from the doors) and add a false wall down each side for return airflow (evaps blowing through product on racks).

I'm a little worried I'll restrict airflow too much for the evap fans

I'd like maximum airflow through the product

I'm think I should add extra fans for airflow sucking from one end of the container to the other

extra heat from fan motors means it would be best to add the motors externally and extend the shaft into the container for the fans

but... by the time I'm doing that... maybe I should remove all the evap fans and just use external powered fans?

3 evaps, 2 fans each, 600watts/fan is 3600watts of heat I'd remove from the containers?

all sounds good, add false walls, remove evap fans, add external powered fans, box in around evaps to direct airflow....

but what if I have too much air flow? how badly will it mess with system performance? - I thought to add motorised TXVs to help with the initial high (ambient) temps and help pull temps down as low as possible?



quick and dirty diagram (only added 1 fan to pic for simplicity)

Untitled.png


so...

is it worth moving fan motor heat out of the container?

will I mess with the evap airflow too much and ruin everything?

[RANGER1]

Knighty,
How do you plan on stacking your product?

[knighty]

right now it's in boxes, in plastic trays, slid into racks down either side of the containers - so we can walk up and down to fill/empty the racks

new system is.... mobile racks so we can fill them in the factory, no plastic trays just boxes straight into racks, and forklift them into the containers

product boxes are about 75mm (3 inch) deep, there's about 50mm (2inch) between each shelf on the rack

there's a few dead sports for airflow right now, some sports freeze much quicker than others etc. etc. - that's why I like the false wall / full length air flow idea