Chicago Pile

Description

A typical 5x5 Chicago Pile design.

The Chicago Pile is a crude early-game breeding reactor meant to produce Plutonium for use as reactor fuel.

A pile is composed of drilled graphite which can hold a variety of items in it, including radioisotope rods (uranium, radium, plutonium), lithium rods, and control rods. It does not behave as a unified single block, instead each individual piece of drilled graphite interacts with each other piece in a unique way depending on the rod it contains.

After sufficient flux, the uranium rods in the Chicago Pile will transmute into plutonium rods that can be processed in a tier 2 anvil or higher into Reactor Grade Plutonium which can be used in other reactors such as the ZIRNOX and RBMK.

Construction

The Chicago Pile requires a significant amount of graphite blocks, which once placed can be drilled into with the hand drill to place any rod into. These rods include:

• Uranium Rod. Fissile breedable fuel though not self sustaining, transmutes into plutonium.
• Plutonium Rod. Neutron source, provides neutrons to initiate or sustain uranium reactions.
• Radium Rod. Neutron source, same as plutonium.
• Lithium Rod. Fertile material, transmutes into tritium.
• Control Rod. Can be set to a downwards position to block flux.
• Control and Detector Rod. Beeps upon detecting neutron flux and can be set to a downwards position to block flux.

The hand drill can be used to drill holes into the graphite or take core samples of the uranium fuel to determine heat, depletion, and neutron flux. Screwdrivers are used to extract rods. Each of these operations take one durability, so obtaining a desh variant of these tools is recommended.

Mechanics

Neutrons

Neutrons are automatically produced by Plutonium and Radium neutron sources which will spread out in 'rays' in every direction. Upon hitting a Uranium rod blocks, the rod will react and then cast rays of its own in every direction as well. The efficiency of this reaction depends on the distance traveled (at 1.5 blocks, the efficiency is greatest) and the heat of the rod (thermal expansion reduces the reaction by up to 50% at maximum heat). 'Rays' have a maximum range of 5 blocks.

Rays can also be blocked entirely by other solid blocks which allows for the isolation of multiple reactors in close proximity to each other for more efficient setups.

Heat

All Uranium rod blocks have a heat value, with a maximum of 1000. The value of neutrons, after reacting, is added to the heat; if the maximum heat is reached, the pile will erupt into a fiery explosion. Cooling can be increased by inserting an aluminum casing into the drilled graphite when no rod is present.

Depletion

Uranium rod blocks have a depletion which the flux experienced by the rod is added to. Upon reaching 50,000 (or 75,000 in 528 Mode), the Uranium rod will transmute into a Plutonium rod which acts a neutron source and does not breed into a new fuel. However, the value of neutrons for each 'ray' is 3 instead of 1 with the regular radium source.

Design

Because of the lack of active cooling for the Chicago pile, designs are necessarily limited in the amount of rods that can arranged together. As such, the typical best option for constructing a pile is to have multiple thin sheets of graphite blocks that contain mostly uranium with a single neutron source to initiate and sustain the reaction. A widely favored design of this sort is featured at the top of the page under "A typical 5x5 Chicago Pile design."

Trivia

• The Chicago Pile is based off of the real Chicago Pile 1, the world's first artificial nuclear reactor built as part of the Manhattan Project.
• Originally, the pile produced unenriched Plutonium, which contained Plutonium-238, however this was later changed to Reactor Grade Plutonium.