Subystud
Chemical
- Jan 12, 2012
- 60
Hello,
I was tasked with assessing a specific cooling tunnel (used equipment, seeing if it will work) for our manufacturing process. The cooling tunnel is a refrigerated cycle blowing cold air in an enclosed space. The conveyor serpentines within the tunnel. So the mechanism of heat transfer is forced convection. From my understanding, the total heat needing to be transferred (to assess the Tons R of the unit) would be mass flow rate of product into tunnel and the difference in the initial and desired temperature. For forced convection, a certain residence time is required in the cooling tunnel. I am assessing for 3 different product sizes (2, 4, and 8oz) but ultimately the unit needs to be capable of the largest load so our largest container.
I wondering if I can get a sanity check on my calcs and my assumptions. I'm calculating that the 8oz product requires 12.5 tonsR and 7.9mins inside the cooling tunnel based on a heat transfer coefficient of 200W/m2*K. The total area for heat transfer I am figuring is the cylinder sides up to the fill height of the product and the open top of the container but not the bottom as this sits on the conveyor. I got a mismatch of imperial and metric units so forgive me, haven't done these calcs since college and metric was easier.
Attached are my calcs and a schematic.
Thanks.
I was tasked with assessing a specific cooling tunnel (used equipment, seeing if it will work) for our manufacturing process. The cooling tunnel is a refrigerated cycle blowing cold air in an enclosed space. The conveyor serpentines within the tunnel. So the mechanism of heat transfer is forced convection. From my understanding, the total heat needing to be transferred (to assess the Tons R of the unit) would be mass flow rate of product into tunnel and the difference in the initial and desired temperature. For forced convection, a certain residence time is required in the cooling tunnel. I am assessing for 3 different product sizes (2, 4, and 8oz) but ultimately the unit needs to be capable of the largest load so our largest container.
I wondering if I can get a sanity check on my calcs and my assumptions. I'm calculating that the 8oz product requires 12.5 tonsR and 7.9mins inside the cooling tunnel based on a heat transfer coefficient of 200W/m2*K. The total area for heat transfer I am figuring is the cylinder sides up to the fill height of the product and the open top of the container but not the bottom as this sits on the conveyor. I got a mismatch of imperial and metric units so forgive me, haven't done these calcs since college and metric was easier.
Attached are my calcs and a schematic.
Thanks.
