액화수소 저장용기 BOG 증발가스 오르토-파라(Ortho-Para) 발열 변환 & 1,000Hz 0-Alloc C# 극저온 촉매 냉각 서보 엔진

using System;
using System.Runtime.CompilerServices;

namespace ZeliDesk.Stem.Chemical.Cryogenics
{
    /// 

    /// 액화수소 오르토-파라 촉매 변환 및 BOG 증발가스 억제 서보 엔진 (0-Alloc C#)
    /// 
    public ref struct LiquidHydrogenBogEngine
    {
        private const double LatentHeatVapJPerKg = 446000.0; // 446 kJ/kg
        private const double DeltaHOrtParaJPerKg = 527000.0; // 527 kJ/kg

        private readonly double _tankVolumeM3;
        private readonly double _heatLeakWatts;              // 진공단열 침입열 (W)
        private readonly double _catalystRateConstantK;      // 촉매 반응속도 계수 (1/s)
        private readonly double _dt;

        private double _currentParaFraction;                 // 0.25 (상온) ~ 0.998
        private double _bogMassFlowKgPerSec;                 // BOG 질량 유량
        private double _tankPressurePa;

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public LiquidHydrogenBogEngine(
            double tankVolumeM3 = 50.0,
            double heatLeakWatts = 120.0,
            double catalystRateConstantK = 0.08,
            double dt = 0.001)
        {
            _tankVolumeM3 = tankVolumeM3;
            _heatLeakWatts = heatLeakWatts;
            _catalystRateConstantK = catalystRateConstantK;
            _dt = dt;
            _currentParaFraction = 0.95; // 초기 주입 농도
            _bogMassFlowKgPerSec = 0.0;
            _tankPressurePa = 101325.0;  // 1 atm
        }

        /// 

        /// 라만 분광 파라 수소 농도와 내압 신호로부터 BOG 발생량 및 촉매 순환 펌프 유량을 제어 (1,000Hz)
        /// 
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public void UpdateCryoStep(
            double measuredParaFraction,
            double currentPressureBar,
            out double bogRateGramsPerSec,
            out double commandedCoolingWatts,
            out bool isPressureReliefNeeded)
        {
            // 액화수소 총 질량: rho ~ 70.85 kg/m^3
            double totalLiquidMassKg = _tankVolumeM3 * 70.85 * 0.9;

            // 2차 반응속도론 농도 진화: dx_p / dt = k * (0.998 - x_p)^2
            double deficit = 0.998 - measuredParaFraction;
            double dxpDt = _catalystRateConstantK * deficit * deficit;
            _currentParaFraction = measuredParaFraction + (dxpDt * _dt);

            // 오르토-파라 전이 방출 발열률: Q_rxn = Delta H * Mass * (dx_p / dt)
            double qReactionWatts = DeltaHOrtParaJPerKg * totalLiquidMassKg * dxpDt;

            // 총 증발 열부하 Q_total = Q_leak + Q_rxn
            double qTotalWatts = _heatLeakWatts + qReactionWatts;

            // BOG 질량 유량: m_dot = Q_total / L_vap
            _bogMassFlowKgPerSec = qTotalWatts / LatentHeatVapJPerKg;
            bogRateGramsPerSec = _bogMassFlowKgPerSec * 1000.0;

            // 재액화기 요구 냉각 용량 지령
            commandedCoolingWatts = qTotalWatts;

            // 탱크 압력 안전 임계치 (3.0 bar 이상 시 비상 벤트 밸브 릴리프)
            isPressureReliefNeeded = currentPressureBar >= 3.0;
        }

        public double CurrentParaFraction => _currentParaFraction;
        public double BogMassFlowKgPerSec => _bogMassFlowKgPerSec;
    }
}