■■Can a submarine hang a net to pull in fish when it is on duty at the bottom of the sea? ■■

First set up a trawl device, similar to the gantry hanger of a container terminal. Based on a 6,000-ton attack nuclear submarine, the trawl frame is about 10~15m high and 5~8m wide.

At the same time, a hydraulic servo mechanism must be added to control the lifting and lowering of the trawl frame. Space must be reserved below the deck to store the trawl frame. The weight of this set of things is about 300~500 tons.

Of course, don’t forget to add isolation fences to the tail rudder and propeller, otherwise it will be difficult to get entangled in the fishing net.

After the fish is caught in the net, it must be collected into the submarine.

It is impossible to directly open the hatch cover to collect fish. A special compartment is required. The space of the compartment is at least 10m×5m×5m. The suitable location is in the motor room or the tail cabin. Both ends are watertight. The hatch is sealed, the back door is connected to the sea water, and the front door is connected to the pressure chamber. A high-pressure drainage mechanism is added.

When closing the net, the rear hatch is opened, the front door is closed tightly, and the compartment is connected to the sea. Put the fishing net into the boat.

After finishing, close the rear hatch and keep the front door tightly closed. Use compressed air to drain the seawater in the compartment; only after the drainage is completed, can the front door be opened and the fish be pulled into the submarine. , so that seawater will not enter the pressure chamber of the submarine.

A whole net of fish cannot be eaten in a short time; underwater ventilation is not good, making dried fish impossible, the only The only feasible way is to refrigerate.

Then we need to build a cold storage inside the submarine. Calculated according to the space volume of the net collection compartment just now, the space of the cold storage cannot be less than 12m×8m×5m. This space It is suitable to be arranged under the sailor's cabin. However, the original battery needs to be located elsewhere.

The refrigeration method can use the reverse principle of the thermocouple, which will not produce noise and does not require refrigerant. However, Whether electromagnetic radiation harmful to the human body will be produced remains to be further studied.

The power supply of the cold storage is also a big difficulty. Ordinary diesel-electric submarines cannot afford it and can only be used by nuclear submarines.

Remember to hire a good cook, otherwise these fresh sea fish will be wasted.

Such a complete set of equipment, roughly calculated, will increase the weight of 1500~3000 tons, a 6000-ton attack nuclear submarine It will reach nearly 10,000 tons. In fact, submarines are at sea, and their food depends on sea supplies.