Reactor Core Thermal-Hydraulics Simulator

Reactor Core

Reactor power 70%

Coolant flow rate 100%

Core inlet

–

Core outlet

–

Peak fuel temp

–

Status

Normal

How it works

Each fuel rod converts fission heat into a temperature rise; the surrounding coolant carries that heat away toward a heat exchanger, exactly like a car radiator loop. The balance between how fast heat is generated and how fast it is removed sets the rod's steady temperature — the classic reactor safety equation:

Q = m · c · ΔT
dT/dt = q_gen(power) − h·flow·(T_rod − T_inlet)

Reactor power — how far the control rods are withdrawn; higher power means more fission heat generated per second in every fuel rod.
Coolant flow rate — pump throughput through the core. Drop it toward zero to simulate a loss-of-coolant accident (LOCA): heat removal collapses while generation continues, so rod temperature climbs unchecked.
SCRAM — drives the control rods fully in, cutting fission heat to a small residual "decay heat" trickle. It fires automatically if peak fuel temperature crosses the fuel-damage threshold, or you can trigger it manually at any time.
Reset core — clears a SCRAM trip and cools the core back to its cold-shutdown baseline.

Rod color tracks temperature from cold blue through green, yellow and orange to white-hot; coolant particles are tinted the same way as they pick up heat rising through the core and cool back down through the heat exchanger before returning to the pump.

⚠ SCRAM — EMERGENCY SHUTDOWN

Cool fuel Warm / hot fuel Danger zone Coolant flow

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