updates

test/basic/hydraulic-model.basic.test.js

@@ -0,0 +1,57 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+
+const { ValveHydraulicModel } = require('../../src/hydraulicModel');
+
+test('hydraulic model gas branch keeps existing formula when not choked', () => {
+  const model = new ValveHydraulicModel({ serviceType: 'gas', gasChokedRatioLimit: 0.9 });
+  const result = model.calculateDeltaPMbar({
+    qM3h: 36,
+    kv: 10,
+    downstreamGaugeMbar: 500,
+    rho: 1.204,
+    tempK: 293.15,
+  });
+
+  const p2AbsBar = (500 / 1000) + 1.01325;
+  const expectedDeltaPMbar = ((36 ** 2 * 1.204 * 293.15) / (514 ** 2 * 10 ** 2 * p2AbsBar)) * 1000;
+
+  assert.ok(result);
+  assert.ok(Math.abs(result.deltaPMbar - expectedDeltaPMbar) < 0.05, `expected ${expectedDeltaPMbar}, got ${result.deltaPMbar}`);
+  assert.equal(result.details.isChoked, false);
+});
+
+test('hydraulic model gas branch applies choked-flow cap', () => {
+  const model = new ValveHydraulicModel({ serviceType: 'gas', gasChokedRatioLimit: 0.2 });
+  const result = model.calculateDeltaPMbar({
+    qM3h: 1000,
+    kv: 1,
+    downstreamGaugeMbar: 500,
+    rho: 1.204,
+    tempK: 293.15,
+  });
+
+  const p2AbsBar = (500 / 1000) + 1.01325;
+  const expectedCappedDeltaPMbar = p2AbsBar * 0.2 * 1000;
+
+  assert.ok(result);
+  assert.equal(result.details.isChoked, true);
+  assert.ok(Math.abs(result.deltaPMbar - expectedCappedDeltaPMbar) < 0.0001, `expected ${expectedCappedDeltaPMbar}, got ${result.deltaPMbar}`);
+});
+
+test('hydraulic model liquid branch uses liquid Kv equation', () => {
+  const model = new ValveHydraulicModel({ serviceType: 'liquid' });
+  const result = model.calculateDeltaPMbar({
+    qM3h: 100,
+    kv: 50,
+    downstreamGaugeMbar: 500,
+    rho: 998,
+    tempK: 293.15,
+  });
+
+  const expectedDeltaPMbar = (((100 / 50) ** 2) * (998 / 1000)) * 1000;
+
+  assert.ok(result);
+  assert.equal(result.details.isChoked, false);
+  assert.ok(Math.abs(result.deltaPMbar - expectedDeltaPMbar) < 0.0001, `expected ${expectedDeltaPMbar}, got ${result.deltaPMbar}`);
+});