From 4533910bce394e7a0ee6debfc05ca1221ee51899 Mon Sep 17 00:00:00 2001 From: victor Date: Sat, 24 Oct 2026 15:57:01 +0200 Subject: Astra! --- src/physics/models.test.ts | 108 --------------------------------------------- 1 file changed, 108 deletions(-) delete mode 100644 src/physics/models.test.ts (limited to 'src/physics/models.test.ts') diff --git a/src/physics/models.test.ts b/src/physics/models.test.ts deleted file mode 100644 index 3ff6487..0000000 --- a/src/physics/models.test.ts +++ /dev/null @@ -1,108 +0,0 @@ -import { describe, expect, it } from 'vitest'; -import { electricField } from './electricField'; -import { potential, forceOn, pairEnergy, gaussianFlux, capacitor, conductor, semiconductor } from './models'; - -// Fixtures use hand-calculated SI results, independent of model implementations. -describe('charge, potential and energy', () => { - const source = [{ x: 0, y: 0, z: 0, coulombs: 2e-9 }]; - it('gives scalar potential tending to zero at infinity', () => { - expect(potential({ x: 2, y: 0, z: 0 }, source)).toBeCloseTo(8.98755, 4); - expect(potential({ x: 1e9, y: 0, z: 0 }, source)).toBeCloseTo(0, 6); - }); - it('makes the field the negative spatial gradient of potential', () => { - const h = 1e-4; - const numerical = -(potential({ x: 2 + h, y: 0, z: 0 }, source) - potential({ x: 2 - h, y: 0, z: 0 }, source)) / (2 * h); - expect(electricField({ x: 2, y: 0, z: 0 }, source).x).toBeCloseTo(numerical, 5); - }); - it('reverses force for a negative test charge', () => { - expect(forceOn({ x: 2, y: 0, z: 0, coulombs: -3e-9 }, source).x).toBeCloseTo(-13.48132768845e-9, 16); - }); - it('gives negative interaction energy for opposite charges', () => { - expect(pairEnergy(2e-9, -3e-9, 2)).toBeCloseTo(-26.9626553769e-9, 16); - }); - it('marks potential at a charge as undefined instead of inventing a finite value', () => { - expect(potential({ x: 0, y: 0, z: 0 }, source)).toBeNaN(); - expect(() => pairEnergy(1, 1, 0)).toThrow(RangeError); - }); -}); - -describe('Gauss law', () => { - it('counts only enclosed charge, including its sign', () => { - const charges = [{ x: 0, y: 0, z: 0, coulombs: -2e-9 }, { x: 3, y: 0, z: 0, coulombs: 5e-9 }]; - expect(gaussianFlux(charges, 2)).toBeCloseTo(-225.8818, 3); - expect(gaussianFlux(charges, 4)).toBeCloseTo(338.8227, 3); - }); - it('does not depend on surface size when enclosed charge is unchanged', () => { - const charges = [{ x: 0, y: 0, z: 0, coulombs: 1e-9 }]; - expect(gaussianFlux(charges, 1)).toBe(gaussianFlux(charges, 2)); - }); - it('marks charge on the Gaussian surface as undefined', () => { - expect(gaussianFlux([{ x: 2, y: 0, z: 0, coulombs: 1e-9 }], 2)).toBeNaN(); - }); -}); - -describe('parallel plate capacitor', () => { - it('converts physical geometry into C, Q, E and stored energy', () => { - const c = capacitor({ area: 0.01, gap: 0.001, relativePermittivity: 1, voltage: 10 }); - expect(c.capacitance).toBeCloseTo(8.8541878128e-11, 18); - expect(c.charge).toBeCloseTo(8.8541878128e-10, 18); - expect(c.field).toBe(10000); - expect(c.energy).toBeCloseTo(4.4270939064e-9, 17); - }); - it('increases free charge at fixed voltage when dielectric is inserted', () => { - const c = capacitor({ area: 0.01, gap: 0.001, relativePermittivity: 4, voltage: 10 }); - expect(c.field).toBe(10000); - expect(c.charge).toBeCloseTo(3.54167512512e-9, 17); - expect(c.polarization).toBeCloseTo(2.65625634384e-7, 15); - }); - it('reduces voltage and energy at fixed free charge', () => { - const c = capacitor({ area: 0.01, gap: 0.001, relativePermittivity: 4, voltage: 10, isolated: true }); - expect(c.charge).toBeCloseTo(8.8541878128e-10, 18); - expect(c.voltage).toBeCloseTo(2.5); - expect(c.field).toBeCloseTo(2500); - expect(c.energy).toBeCloseTo(1.1067734766e-9, 17); - }); - it('rejects impossible geometry', () => { - expect(() => capacitor({ area: 0.01, gap: 0, relativePermittivity: 1, voltage: 10 })).toThrow(RangeError); - }); -}); - -describe('current and drift', () => { - it('follows Ohm law and sends electrons opposite conventional current', () => { - const wire = conductor({ voltage: 2, resistivity: 1.68e-8, length: 1, area: 1e-6, carrierDensity: 8.5e28 }); - expect(wire.resistance).toBeCloseTo(0.0168, 6); - expect(wire.current).toBeCloseTo(119.047619, 5); - expect(wire.electronDrift).toBeCloseTo(-0.00874160935, 10); - expect(wire.power).toBeCloseTo(238.095238, 5); - }); - it('reverses current but keeps dissipated power positive with reversed voltage', () => { - const wire = conductor({ voltage: -2, resistivity: 1.68e-8, length: 1, area: 1e-6, carrierDensity: 8.5e28 }); - expect(wire.current).toBeLessThan(0); - expect(wire.electronDrift).toBeGreaterThan(0); - expect(wire.power).toBeGreaterThan(0); - }); -}); - -describe('semiconductor equilibrium at 300 K', () => { - it('has equal intrinsic electrons and holes', () => { - const s = semiconductor({ intrinsicDensity: 1e16, netDoping: 0, electronMobility: 0.135, holeMobility: 0.048 }); - expect(s.electrons).toBe(1e16); - expect(s.holes).toBe(1e16); - expect(s.fermiShift).toBe(0); - expect(s.conductivity).toBeCloseTo(0.0002931983, 9); - }); - it('conserves mass action and charge neutrality even at heavy donor doping', () => { - const s = semiconductor({ intrinsicDensity: 1e16, netDoping: 1e22, electronMobility: 0.135, holeMobility: 0.048 }); - expect(s.electrons / 1e22).toBeCloseTo(1, 10); - expect(s.holes).toBeCloseTo(1e10, 0); - expect(s.electrons * s.holes / 1e32).toBeCloseTo(1, 12); - expect((s.electrons - s.holes) / 1e22).toBeCloseTo(1, 12); - expect(s.fermiShift).toBeCloseTo(0.3571586, 5); - }); - it('makes holes majority carriers for acceptor doping', () => { - const s = semiconductor({ intrinsicDensity: 1e16, netDoping: -1e22, electronMobility: 0.135, holeMobility: 0.048 }); - expect(s.holes / 1e22).toBeCloseTo(1, 10); - expect(s.electrons).toBeCloseTo(1e10, 0); - expect(s.fermiShift).toBeLessThan(0); - }); -}); -- cgit v1.2.3