Cryo rounds are designed to combat regenerative capabilities of entities like the Enhanced Type Mishhuvurthyar. Launched from a "Taihō" Scalable Mass Driver, each round contains Liquid Helium, cooled to absolute zero. Upon hitting the target, the ammunition delivers a multi-layered effect. The liquid helium induces rapid cooling, flash freezing biological tissues and other materials, making them brittle and susceptible to further damage. This freezing effect specifically targets the regenerative capabilities of Mishhuvurthar by solidifying hemosynth, effectively halting regeneration. It is a niche ammunition type in limited production for use by the Star Army of Yamatai

Inspired by a recount from Taisa Taiyou Hoshi about an encounter with an Enhanced Type Mishhuvurthar, Shoi Morgana Faelan designed this unique type of ammunition. The incident involved the creature being incapacitated on a mountain side, where the cold environment interfered with its regenerative abilities due to hindered hemosynth flow. Shoi Faelan then developed a dart off this idea consisting of a helium canister at its tip, accompanied by a femtomachine heat exchanger within its shaft. The heat exchanger would quickly heat up, glowing red and eventually white hot before failing after about a minute of readiness, leading to a short window between the round being primed and fired. Following a successful field test in which it was used to great effect against an Advanced Type Shoi Faelan iterated on the concept to address its short comings.

The Taihou SMD was chosen as the base platform due to its modularity and two rounds were designed for production, one based of the standard 10x50mm round for man portable use and one based off the 15x75mm round for power armored use. While instructions can be adapted to any configuration, the default configuration is a “Service Rifle” (Bullpup) configuration. A small batch of rounds were produced via shipboard nanofabricators before being licensed out to Yugumo.

The ammunition is specifically designed to freeze hemosynth, the regenerative substance in Mishhuvurthar, thereby halting their healing process and amplifying the impact of sustained damage. Operators utilising this ammunition shouldn't be considered primary damage dealers, rather they can fire on existing wounds to “Lock in” damage to entities relying on hemosynth regeneration.

Despite its niche design, Cryo ammunition is devastating against various targets if used in a primary damage dealer role.

- Thermal Shock: The phase transition from a liquid to a gas absorbs a significant amount of heat from the environment, causing thermal shock to almost anything in contact with it, be it organic, ceramic or metallic in nature. Thermal Shock causes the material affected to both become extremely brittle and rapidly contract, creating a thermal gradient inducing high stress which can cause failure.

- Rapid Expansion: When Liquid helium transitions to a gas, it undergoes rapid expansion. This expansion is due to the increase in kinetic energy of the helium atoms as they absorb heat from the environment or the target, transitioning from a nearly zero-entropy superfluid state to a higher-entropy gaseous state. Under certain conditions this rapid expansion of gas can have explosive effects.

- Zero Viscosity: Liquid Helium is in a special phase state called a Superfluid. One property of this phase known as Zero Viscosity which allows the fluid to flow between narrow channels with no friction generation. What this effectively means is that any porous object can be infiltrated by liquid helium. Though the time between impact and phase change is short and violent, the infiltration is quick enough to cause limited penetration.

- No Thermal Gradient: Liquid Helium is condensed to the point in which inter atomic forces are so low quantum effects become more pronounced. All atoms within a contiguous section share a quantum state. As a result, temperature differences within the superfluid are quickly equalized, preventing the establishment of a thermal gradient. The superfluid essentially acts as a perfect thermal conductor. This has a side effect of causing a synchronised phase change across the entire material, further compounding the explosive effects.

- Mechanical Stress: The sudden increase in pressure can exert substantial mechanical stress on the surrounding material. If the transition occurs upon or shortly after impact, this stress can contribute to the fracturing or disintegration of the target material, compounding the damage caused by the initial impact and the extreme cold.

Effect is limited on hard targets with poor thermal conductivity. It is ineffective against Zesuanium armored targets for this reason.

- Shell - An outer shell of Aggregated Diamond Nanorods (ADNR) and an inner shell of Boreanium Alloy. The ADNR layer provides exceptional tensile strength and electrical conductivity, serving both as a structural backbone and an electrical conduit for the mass driver's rails. Boreanium, a semi-metallic alloy, insulates the helium charge, preserving its supercooled state by preventing heat absorption from the surroundings. The shell is shaped with a star pattern at its tip, similar to a hollow point to ensure the round breaks apart on impact.

- Helium Charge - Pressurized helium is loaded into the vessel at 293K with a pressure of 1000 atmospheres, giving it a molar density of 36.25mol/L. Its temperature is lowered to .01K via a mechanism within the magazine

Standard 30 round Taihou magazines are taken as a base and modified with the required components. Magazines are expensive comparatively so operators using the system are encouraged to recover them.

- Cooling Unit - A femtomachine heat exchanger is added to the back of the magazine facilitates rapid cooling of the helium to absolute zero by absorbing heat energy and transferring it to a heat sync within the magazine. The heat sync is in a sealed flask filled with liquid nitrogen to keep the magazine handleable after firing all rounds. The cooling is quick but not instantaneous, each round taking up to a second to cool from 293K. To speed up fire rate the heat exchanger cools 4 rounds simultaneously and is only started at the pull of the trigger.

- Feed system - Rather than being spring loaded like traditional magazines, the rounds are pushed into the weapon by a small linear actuator. The actuator is controlled by a temperature sensor located at the feed lips. Initial shot from a fresh magazine is normally 1 second after a full press of the trigger, then a sustained rate of 240 RPM.

- Firmware - The Taiho rifle needs to have an additional mode added. In this mode the rails are always active when the trigger is half pulled and firing is governed by the magazine. Voltage is limited to reduce Muzzle velocity in order to limit heating due to air friction.

- Receiver - Alterations need to be made to the receiver to accept magazines with slightly bulkier backs going into the breech as the heat exchanger is in contact until just before firing

- Trigger - A 2 stage trigger is introduced. At a half pull the heat exchanger is activated without the feed system loading a round into the breech. This primes a round without firing it, allowing for greater precision.

- Standard Rounds - Efforts have been made to preserve the default functions of the Talhou SMD. It can switch to plasma casting with no issue, however standard issue magazines must be altered to interface with the receiver alterations.

Heilium is not the only element that can be reduced to a superfluid. Alkali metals can also be condensed.

Heilium, specifically Heilium-4 was selected as the medium as its Molar Heat Capacity is 20.78 J/(mol·K) and its molar density at Lambda Point is 36.25mol/L, giving it a specific heat capacity of 753.275 J/L·K.

Rubidium-87 is one of the best candidates in the Alkali metal group for use in this capacity, and has a molar heat capacity of 31.060 J/(mol·K), but its molar density is 17.632 mol/L, giving it a specific heat capacity of 547.655 J/L·K.

Despite the lower energy deficit, Rubidium may have other advantages. Rubidium is heavier and could enable the projectile to travel greater ranges. In addition their are interesting quantum properties of Alkali metals that include wave form manipulation. It may be possible to utilise these effects to allow for greater penetration or fluid coherence, which would improve energy transfer of the medium despite the lower energy deficit.

Sunny D created this article on 2024/03/12 06:06 and it was approved here.