Beta 9

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assets/js/physics.js

@@ -7,13 +7,15 @@
 //    solarElevationDeg(lat, lon, dateUTC) NOAA simplified solar position
 //    calcTmrt(Ta, dirRad, diffRad, globalRad, solElev)  Mean radiant temp
 //    utciApprox(Ta, Tmrt, va10, ehPa)     Bröde et al. 2012 polynomial
-//    calcVehicleInteriorTemp(Ta, globalRad, solElev, vehicleType)
+//    calcVehicleInteriorTemp(Ta, globalRad, solElev, vehicleType, ventilated)
+//    calcIndoorTempPass(TaArr, globArr, elevArr, buildingType)
+//    calcManagedIndoorTempPass(TaArr, globArr, elevArr, buildingType)
 //
 //  Nothing in here should need editing unless the underlying science
 //  changes. All numbers are peer-reviewed constants or coefficients.
 // ════════════════════════════════════════════════════════════════════════
 
-import { VEHICLE_TYPES } from './utils.js';
+import { VEHICLE_TYPES, BUILDING_TYPES } from './utils.js';
 
 // ═══════════════════════════════════════════════════════════════════
 // PHYSICAL CONSTANTS
@@ -120,48 +122,37 @@ function _houseHeatLoad(Ta, globalRad, solElev) {
 
 // Two-pass function: call with the full arrays of hourly Ta and globalRad.
 // Returns an array of indoor temperatures, one per hour.
-export function calcIndoorTempPass(TaArr, globArr, elevArr) {
+// buildingType must be a key of BUILDING_TYPES; defaults to 'brick'.
+export function calcIndoorTempPass(TaArr, globArr, elevArr, buildingType = 'brick') {
+  const preset = BUILDING_TYPES[buildingType] || BUILDING_TYPES.brick;
+  const { uWall, lagHours, glazingRatio, gValue, orientFactor } = preset;
+
   const n = TaArr.length;
   const result = new Array(n);
-
-  // Thermal resistance of the building envelope (°C per W/m² of heat load)
-  // Lower = faster response to outdoor changes. UK brick mid-stock ~0.45.
-  const uWall    = 0.35;   // W/m²K effective wall U-value
-  // Thermal mass time constant: heavier = longer lag.
-  // ~4 h lag for typical UK brick semi (expressed as exponential decay weight).
-  const lagHours = 4;
-  const alpha    = 1 - Math.exp(-1 / lagHours); // per-hour blending weight
+  const alpha = 1 - Math.exp(-1 / lagHours); // per-hour blending weight
 
   // Seed indoor temp to first outdoor temp
   let Ti = TaArr[0] ?? 15;
 
   for (let i = 0; i < n; i++) {
-    const Ta      = TaArr[i]  ?? Ti;
-    const glob    = globArr[i] ?? 0;
-    const solElev = elevArr[i] ?? 0;
+    const Ta   = TaArr[i]  ?? Ti;
+    const glob = globArr[i] ?? 0;
 
     // Solar gain through windows (W/m² effective)
-    const glazingRatio = 0.16;
-    const gValue       = 0.63;
-    const orientFactor = 0.50;
-    const solarGain    = glob * glazingRatio * gValue * orientFactor;
+    const solarGain = glob * glazingRatio * gValue * orientFactor;
 
     // Conductive heat flow through walls: proportional to (Ta - Ti)
-    // uWall drives how quickly the indoor temp chases outdoor temp.
     const conductionGain = uWall * (Ta - Ti);
 
-    // Target indoor temp this hour if there were no thermal mass:
-    // Ti_instant = Ti + conduction + solar load / heat capacity proxy
-    // heatCap proxy: how many degrees does 1 W/m² raise the indoor air?
-    // For a typical 90 m² house, ~0.15 °C per W/m² effective.
+    // Heat capacity proxy: how many °C does 1 W/m² raise the indoor air?
+    // Typical 90 m² house ≈ 0.15; conservatory much lower (less thermal mass).
     const heatCapProxy = 0.15;
     const Ti_instant = Ti + (conductionGain + solarGain) * heatCapProxy;
 
-    // Apply thermal lag: blend toward Ti_instant slowly
+    // Apply thermal lag: blend toward Ti_instant at the building's time constant
     Ti = Ti + alpha * (Ti_instant - Ti);
 
     // Can't be colder than outdoor (house doesn't actively cool)
-    // Cap at 55 °C (physically implausible above this for a house interior)
     result[i] = Math.max(Math.min(Ti, 55), Math.min(Ta, Ti));
   }
 
@@ -188,20 +179,14 @@ export function calcIndoorTempPass(TaArr, globArr, elevArr) {
 //
 // Same thermal lag model as calcIndoorTempPass (4 h brick time constant).
 // ═══════════════════════════════════════════════════════════════════
-export function calcManagedIndoorTempPass(TaArr, globArr, elevArr) {
+// buildingType must be a key of BUILDING_TYPES; defaults to 'brick'.
+export function calcManagedIndoorTempPass(TaArr, globArr, elevArr, buildingType = 'brick') {
+  const preset = BUILDING_TYPES[buildingType] || BUILDING_TYPES.brick;
+  const { uWall, lagHours, glazingRatio, gValue, orientFactor, curtainBlock, ventAlpha } = preset;
+
   const n = TaArr.length;
   const result = new Array(n);
-
-  const uWall    = 0.35;
-  const lagHours = 4;
-  const alpha    = 1 - Math.exp(-1 / lagHours);
-
-  // Curtain factor: blocks 80% of solar gain
-  const curtainBlock = 0.80;
-
-  // Ventilation blending weight per hour when windows are open
-  // ~2 ACH for a well-ventilated house → meaningful but not instant pull
-  const ventAlpha = 0.25;
+  const alpha = 1 - Math.exp(-1 / lagHours);
 
   let Ti = TaArr[0] ?? 15;
 
@@ -209,13 +194,10 @@ export function calcManagedIndoorTempPass(TaArr, globArr, elevArr) {
     const Ta   = TaArr[i]  ?? Ti;
     const glob = globArr[i] ?? 0;
 
-    // Solar gain — curtains block 80%
-    const glazingRatio = 0.16;
-    const gValue       = 0.63;
-    const orientFactor = 0.50;
-    const solarGain    = glob * glazingRatio * gValue * orientFactor * (1 - curtainBlock);
+    // Solar gain — curtains block curtainBlock fraction
+    const solarGain = glob * glazingRatio * gValue * orientFactor * (1 - curtainBlock);
 
-    // Wall conduction (unchanged)
+    // Wall conduction (unchanged from unmanaged model)
     const conductionGain = uWall * (Ta - Ti);
 
     const heatCapProxy = 0.15;
@@ -265,7 +247,7 @@ export function calcManagedIndoorTempPass(TaArr, globArr, elevArr) {
 //   35–45 °C — dangerous for children/pets (hyperthermia risk)
 //   > 45 °C  — potentially fatal within minutes
 // ═══════════════════════════════════════════════════════════════════
-export function calcVehicleInteriorTemp(Ta, globalRad, solElev, vehicleType = 'car') {
+export function calcVehicleInteriorTemp(Ta, globalRad, solElev, vehicleType = 'car', ventilated = false) {
   if (globalRad == null || Ta == null) return null;
 
   // Look up vehicle preset; fall back to a standard car if key unknown.
@@ -303,8 +285,12 @@ export function calcVehicleInteriorTemp(Ta, globalRad, solElev, vehicleType = 'c
   // ── Combine into cabin air temperature ───────────────────────────
   // Total heat input per m² of cabin surface
   const totalGain = conductionGain + glazingGain;
-  // Cabin heat loss: varies by vehicle type (motorhomes insulated, cars not)
-  const Ti = Ta + totalGain / preset.hCabinLoss;
+  // Cabin heat loss: varies by vehicle type (motorhomes insulated, cars not).
+  // With windows open, convective loss is roughly 5× higher — air moves freely
+  // through the cabin, flushing heat out and capping interior temperature much
+  // closer to ambient. Cabin temp still rises a little due to panel/roof solar gain.
+  const effectiveHLoss = ventilated ? preset.hCabinLoss * 5 : preset.hCabinLoss;
+  const Ti = Ta + totalGain / effectiveHLoss;
 
   // Clamp: can't be cooler than outside air; physical cap at 90 °C
   return Math.max(Ta, Math.min(Ti, 90));