Test 1 allowed the team to determine if the rainfall system would provide enough water to each crate in the stack to sustain the lobsters during short-term storage (stored for less than 24 hours). Requirement 4 indicates that the storage system shall hold and keep the lobsters alive for up to 48 hours. A prototype was constructed for one pallet to resemble the height and layout of the new spray design. This allowed the project team and partners to view the water flowing overtop of the stacked crates from all angles to determine if it made it to the bottom crates and how the water moved through the holes in the crates. Since the lobster crates will traditionally be filled with 100 lbs of lobster during storage and to prevent testing on real lobsters, various-sized balloons were used to occupy space and not absorb the water.

The prototype sprung a leak near the water hose connection during initial testing. Even so, the prototype operated well with the reduced pressure. Starting with the stacked, empty crates, each of the three nozzles was tested for approximately 5 minutes or until the water sufficiently coated all of the crates. Then, the crates were filled with balloons, and the sides were lined with paper towels. This was to ensure that, along with the visual confirmation, the paper indicated that the water reached all around the crates. The three nozzles were each successful in getting the water through the crates. The PVDF 2.7 GPM nozzle misted the water overtop of the crates. The water reached the bottom-most crates, but the flow was minimal. The other two nozzles tested (clog-resistant 0.19” and 0.25” diameter) warranted similar results. The 0.19” nozzle gave about 5 GPM, and the 0.25” about 9 GPM at 30 psi. The higher flow would be beneficial for purging the crates initially, but it is too much for what is needed.

The 0.19” nozzle seemed to warrant similar flow results to the larger one, just taking an extra minute for the water to go through the full stack of crates. The partners preferred the results from the clog-resistant nozzles and commented on the effectiveness of the water moving through the crates. They believe the water provided through the rainfall system will sufficiently store the lobsters.  

The height of the spray was approximately 14.5” up from the top-most crates. This is the maximum height that remains overtop of the stacked crates and the ceiling of the shipping container. At this height, the spray remained centrally located over the pallet and the water dispersed throughout the crates. From the testing, we have decided that 14.5” will be the minimum distance between the top of the crate and the ceiling of the shipping container to obtain valuable flow throughout the crates; wouldn’t suggest exceeding 20”. 

After completing the first two trials, with and without the balloons, the stacked lobster crates were wrapped in plastic wrap while the crates were filled with balloons. Bait Masters already wraps the pallets in plastic before loading them on the truck. This test determined if the plastic would keep the water within the crates more than without. The water hitting the covers of the crates retained within the stack more than without the wrap. However, the difference between the two is fairly insignificant in regard to keeping the lobsters wet.

Alongside completing the tests, the team also spoke with Spencer Greenwood, who recommended Dan Paynter from the Atlantic Veterinary College (AVC). Dan is the Animals Resource Manager in the AVC, with experience/expertise in handling and storing lobsters. The team met virtually with Dan to get his opinion on our design and anything that may have concerned him about the design. He mentioned that it shouldn’t be an issue and that the lobsters should be supplied with sufficient oxygen as long as they are wet. The testing revealed that the nozzle spray provided enough water within all the crates to suggest that the lobsters would survive. Through this testing and conversations with Dan Paynter, requirement #4 is satisfied. Where the lobsters shall survive being stored short term (less than 48 hours) in the rainfall holding tank. 

Prior to testing, the team estimated that the nozzles would require 6 GPM of flow, meaning a total of 160 GPM at 30 psi would be required for the internal pump within the design. After outsourcing to Jeff Benoit and Andrew from Flowstar, it seemed that it was too large of a pump to operate with the available resources Bait Masters has on-site. Upgrading any of their services, such as electrical and compressed air, costs too much to be feasible for this project. The team decided it would take half the load if we incorporated two pumps to each supply half of the rainfall system. This decision brought the size of the pump down to 80 GPM at 50 ft total head. A pump was found on Absolute Water Pumps [1]; they cost approximately $2000 each, meaning that the two pumps will cost less than sourcing just one. It also brings the opportunity for Bait Masters to control either side of the container separately if needed.