심부 지열발전(EGS) 수압파쇄 균열 진전 & 1,000Hz 0-Alloc C# 미소 유도지진(Induced Seismicity) 모멘트 텐서 서보 엔진

using System;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;

namespace ZeliDesk.Stem.GeothermalSafety
{
    /// <summary>
    /// 3축 지진계 가속도 및 시추공 주입압 데이터 (스택 할당 0-Alloc)
    /// </summary>
    [StructLayout(LayoutKind.Sequential, Pack = 8)]
    public readonly struct BoreholeSeismicData
    {
        public readonly double AccelX; // m/s^2
        public readonly double AccelY;
        public readonly double AccelZ;
        public readonly double InjectionPressureMPa;
        public readonly double FlowRateLitersPerMin;

        public BoreholeSeismicData(double ax, double ay, double az, double pMpa, double flowLpm)
        {
            AccelX = ax; AccelY = ay; AccelZ = az;
            InjectionPressureMPa = pMpa;
            FlowRateLitersPerMin = flowLpm;
        }
    }

    /// <summary>
    /// 수압 주입 제어 및 비상 감압 명령
    /// </summary>
    public ref struct HydraulicReliefCommand
    {
        public double PumpThrottlePercent;   // 0.0 ~ 100.0%
        public double BleedValveOpenPercent; // 0.0 ~ 100.0%
        public int TrafficLightStatus;       // 0: Green, 1: Amber, 2: Red
        public double EstimatedMagnitudeMw;

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public HydraulicReliefCommand(double pump, double bleed, int tls, double mw)
        {
            PumpThrottlePercent = pump;
            BleedValveOpenPercent = bleed;
            TrafficLightStatus = tls;
            EstimatedMagnitudeMw = mw;
        }
    }

    /// <summary>
    /// 1,000Hz 무할당 EGS 유도지진 방호 서보 엔진
    /// </summary>
    public ref struct EgsInducedSeismicityEngine
    {
        private const double ShearModulusMu = 3.2e10; // 화강암 전단 탄성률 32 GPa
        private const double GreenThresholdMw = 0.5;  // 정상 미세 파쇄 상한
        private const double AmberThresholdMw = 1.2;  // 감압 필요 경계치
        private const double RedThresholdMw = 2.0;    // 즉시 중단 및 긴급 감압

        private double _pgaHistoryMax;

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public void ExecuteMonitoringCycle(
            in BoreholeSeismicData seismic,
            double nominalTargetPressureMPa,
            out HydraulicReliefCommand command,
            out double seismicEnergyJoules)
        {
            // 1. 최대 지반 가속도(PGA) 계산
            double pga = Math.Sqrt(seismic.AccelX * seismic.AccelX + seismic.AccelY * seismic.AccelY + seismic.AccelZ * seismic.AccelZ);
            if (pga > _pgaHistoryMax) _pgaHistoryMax = pga;

            // 2. 가속도로부터 모멘트 규모(Mw) 추정 (경험적 스케일링 관계식)
            // Mw ~ (log10(PGA) + 3.2) / 1.5
            double estimatedMw = (Math.Log10(Math.Max(pga, 1e-6)) + 3.2) / 1.5;

            // 지진 에너지 E = 10^(1.5 * Mw + 4.8) 줄
            seismicEnergyJoules = Math.Pow(10.0, 1.5 * estimatedMw + 4.8);

            // 3. 신호등 시스템(Traffic Light System: TLS) 기반 피드백 제어
            int tlsStatus = 0; // Green
            double pumpThrottle = 100.0;
            double bleedOpen = 0.0;

            if (estimatedMw >= RedThresholdMw)
            {
                tlsStatus = 2; // Red (즉시 셧다운 & 최대 감압)
                pumpThrottle = 0.0;
                bleedOpen = 100.0;
            }
            else if (estimatedMw >= AmberThresholdMw)
            {
                tlsStatus = 1; // Amber (주입량 50% 감축 및 미세 감압)
                pumpThrottle = 40.0;
                bleedOpen = 30.0;
            }
            else
            {
                tlsStatus = 0; // Green (정상 균열 확장)
                double pressDiff = nominalTargetPressureMPa - seismic.InjectionPressureMPa;
                pumpThrottle = Math.Clamp(80.0 + pressDiff * 5.0, 10.0, 100.0);
                bleedOpen = 0.0;
            }

            command = new HydraulicReliefCommand(pumpThrottle, bleedOpen, tlsStatus, estimatedMw);
        }
    }
}