Major Update

Patch notes: V 2.2.21.172

A major update to our nuclear reactor simulator, which has transitioned from a small core model to a new, enhanced core capable of supporting multiple fuel blocks and significantly increased power output.

Enhanced Core

The new core design now accommodates nine fuel blocks and seventy-two control rods (eight per block), significantly expanding the reactor’s capabilities. Additionally, a system of nine hatches and safety pistons has been integrated into the core for improved safety and maintenance access.

Relationship between Thermal Power and Temperature

Thermal power in a nuclear reactor refers to the amount of thermal energy generated by the fission of uranium or plutonium nuclei in the fuel blocks. This thermal energy results from the nuclear fission process, where the fuel nuclei split into smaller fragments, releasing a significant amount of heat in the process.

Although the thermal power of a reactor with multiple fuel blocks (such as the new core) is greater than that of a reactor with a single fuel block (like the old core), both can operate at similar temperatures. This is because the maximum operating temperature is determined by the reactor's design.

Higher Energy Generation Capacity: A reactor with more fuel blocks can generate more total thermal energy because it can achieve more fissions simultaneously. Even though the system's temperature is maintained within a safe range, the total amount of energy produced is greater.

Efficiency in Energy Conversion: Despite having a similar temperature, the efficiency of the system in converting that thermal energy into electrical energy can be better in a reactor with multiple fuel blocks. With more thermal energy available, the generation cycle can operate under optimal conditions, maximizing electricity production.

Adding more fuel blocks does not necessarily increase the reactor's temperature if the control and cooling systems are adequate. Control rods and cooling systems are designed to manage the amount of heat produced and keep it within safe limits. Thus, the reactor can generate more energy without raising the temperature beyond permissible levels.

New capabilities

To improve safety, we have introduced three tiers of resistance banks (Class A, B, and C), along with corresponding spare parts and transformers. This allows for better customization and adaptability of the reactor’s systems. Furthermore, circulation pumps now also have three levels (Class A, B, and C) to enhance fluid dynamics within the reactor.

Control Rod Management

Each bank of control rods is now equipped with its own control rod motor, allowing for more precise adjustments. We have also added a control rod status panel in the control room to provide operators with real-time monitoring of control rod positions. Similarly, a fuel block status panel has been included to keep track of the fuel blocks’ conditions.

When you have more control rods than fuel blocks, the ability of these rods to manage the reaction is enhanced. However, it’s important to understand that each fuel block has a specific number of associated control rods to maintain a proper balance. This means that:

Adequate Control: With more control rods than fuel blocks, each block is "over-controlled." This makes it harder to initiate the reaction because the control rods are absorbing more neutrons than are being generated.
Extraction of Rods: If you decide to extract the control rods, the chain reaction will not start immediately. This is because, to initiate fission, you need a sufficient number of free neutrons that can induce chain reactions. If there are too many control rods compared to fuel blocks, you will need to extract a significant amount of rods to release enough neutrons and reach the necessary reactivity threshold.
Reactivity Threshold: The chain reaction begins only when the number of free neutrons exceeds the number that the control rods can absorb. Therefore, if you have a disproportionate number of control rods, you will need to extract an "excessive" amount to allow the chain reaction to start effectively. Only by reducing the number of rods below a certain point will it allow neutrons generated by fission to trigger more fissions in a continuous cycle.

Safety Features and Access

An underground access building has been implemented to facilitate maintenance across three levels of the core. Each of these levels is equipped with safety gates to ensure secure operations during maintenance procedures.

Operational Enhancements

Our new "Operational Tasks" application on the operator’s tablet allows for efficient management of reactor functions. Operators can now perform tasks such as fuel block loading/unloading and control rod loading/unloading directly from their devices.

And we’ve added the ability to control AO remotely, allowing for greater flexibility in managing reactor components. Operators can now energize various plant elements using the AO tool, further enhancing operational efficiency.

System Calculations and Adjustments

Significant modifications have been made to improve the absorption capacity of control rods and to optimize the performance of circulation pumps. The city demand calculation is now relative to the plant’s installed power, allowing for more realistic simulations.

Moreover, we’ve fine-tuned the fuel consumption balance and evaporator pressure calculations to enhance overall system efficiency. Notably, the valves previously known as Admit Valves have been renamed to Main Steam Control Valves, reflecting their updated functionality.

Evaporator Code Overhaul

The evaporator code has been completely rewritten to address various gameplay issues and enhance realism. The updated evaporators now incorporate the concept of thermal power, meaning that the evaporation rate is now directly related to the reactor’s power output. This change allows for a more accurate simulation of the evaporation process, improving the overall gameplay experience.

Improvements to pressure calculations within the evaporator may now lead to situations where circulation pump power is insufficient to counteract internal pressure, potentially hindering coolant recirculation through the secondary circuit. To mitigate this, we have implemented pressure relief valve controls to manage excess pressure more effectively.

Pipe Adaptations and Valve Functionality

The pipes in the secondary circuit have been adapted to align with the new core's power requirements. In low-power settings, filling times are now extended due to the increased size of the pipes, which are designed to accommodate maximum coolant or steam flow.

The operation of the Main Steam Control Valves and Bypass Valves has been modified to operate with fixed capacities rather than relative ones. This change ensures that if a valve is opened to 10%, coolant will pass at 10% of the valve’s maximum capacity. We’ve also introduced the concept of a Low-Flow Free-Passage Regime, allowing unrestricted flow even when a valve is partially closed, provided there’s low demand or a low-pressure differential.

Performance Enhancements

A series of performance improvements have been implemented to optimize the game’s overall efficiency and responsiveness, ensuring a smoother and more enjoyable gameplay experience.