diff --git a/Services/LanScpiSocket.cs b/Services/LanScpiSocket.cs
index 778333b..a24132e 100644
--- a/Services/LanScpiSocket.cs
+++ b/Services/LanScpiSocket.cs
@@ -94,7 +94,7 @@ namespace ASTM_D7896_Tester.Services
await SendCommandAsync($"VOLT:DC:RANG {DefaultVoltageRange}");
// 3. 设置积分时间 0.02PLC（最快速度）
- await SendCommandAsync("VOLT:DC:NPLC 0.02");
+ await SendCommandAsync("VOLT:DC:NPLC 10");
// 4. 关闭自动归零（提高速度）
await SendCommandAsync("VOLT:DC:ZERO:AUTO OFF");
diff --git a/ViewModels/D7896ViewModel.cs b/ViewModels/D7896ViewModel.cs
index c7c4286..ca055e2 100644
--- a/ViewModels/D7896ViewModel.cs
+++ b/ViewModels/D7896ViewModel.cs
@@ -88,6 +88,7 @@ public partial class D7896ViewModel : ObservableObject
[ObservableProperty] private double _sampleDensity = 1000.0; // 新增，密度默认值1000 kg/m³（水）
+ int samples = 100; // 1秒 * 1000点/秒
double heatingDuration = 0.8; // 加热时间 0.8 秒（需与您的加热脉冲宽度一致）
double totalDuration = 1.6; // 总采样时间（加热 + 冷却）
public D7896ViewModel()
@@ -271,19 +272,39 @@ public partial class D7896ViewModel : ObservableObject
CurrentMeasurementIndex = i;
StatusMessage = $"正在执行第 {i} 次测量...";
- // 准备批量采集参数（每通道采样点数，采样率1000点/秒，加热时间1秒 -> 1000点）
- int samples = 200; // 1秒 * 1000点/秒
- // 预配置两台表：进入等待触发状态
+ // === 新增：在加热前，单独测量冷态初始电阻 R0 ===
+ StatusMessage = $"第 {i} 次测量：正在获取冷态电阻...";
+ await _th1963Ustd.PrepareBatchAsync(20);
+ await _th1953Ustd.PrepareBatchAsync(20);
+ await Task.WhenAll(_th1963Ustd.TriggerAsync(), _th1953Ustd.TriggerAsync());
+ await Task.Delay(250); // 等待采集完成
+ double[] ustd_r0 = await _th1963Ustd.FetchBatchAsync();
+ double[] upt_r0 = await _th1953Ustd.FetchBatchAsync();
+
+ double sumR0 = 0;
+ int validR0Count = 0;
+ for (int j = 2; j < ustd_r0.Length; j++) // 跳过前2个不稳定点
+ {
+ if (ustd_r0[j] > 0.01)
+ {
+ sumR0 += upt_r0[j] / ustd_r0[j]; // R = Upt / I = Upt / (Ustd / 1Ω)
+ validR0Count++;
+ }
+ }
+ double dynamicR0 = validR0Count > 0 ? sumR0 / validR0Count : 2.34; // 给个默认值防错
+ Logger.Log($"冷态测量 R0 = {dynamicR0:F6} Ω");
+
+ // === 正式加热与采集 ===
await _th1963Ustd.PrepareBatchAsync(samples);
await _th1953Ustd.PrepareBatchAsync(samples);
// 启动加热脉冲 (PLC)
await _plcService.WriteCoilAsync(_config.PlcRegisterAddresses.StartCommand, true);
-
try { await Task.Delay(5, _testCts.Token); } catch (OperationCanceledException) { break; }
- // 同时发送触发信号给两台电压表
+
+ // 触发采集
await Task.WhenAll(_th1963Ustd.TriggerAsync(), _th1953Ustd.TriggerAsync());
// 等待加热结束
@@ -292,28 +313,22 @@ public partial class D7896ViewModel : ObservableObject
// 停止加热
await _plcService.WriteCoilAsync(_config.PlcRegisterAddresses.StartCommand, false);
- // 等待采集完成（剩余时间）
+ // 等待采集完成
int remainingMs = (int)((totalDuration - heatingDuration) * 1000) + 100;
try { await Task.Delay(remainingMs, _testCts.Token); } catch (OperationCanceledException) { break; }
// 获取采集数据
double[] ustd = await _th1963Ustd.FetchBatchAsync();
double[] upt = await _th1953Ustd.FetchBatchAsync();
- for (int j = 0; j < 20; j++)
+
+ for (int j = 0; j < 20 && j < ustd.Length; j++)
{
Logger.Log($"第{j}点: U_std={ustd[j]:F6} V, U_pt={upt[j]:F6} V");
}
-
-
-
-
-
StandardResistorVoltage = ustd.Average();
PlatinumVoltage = upt.Average();
- // 添加日志：原始电压统计
- Logger.Log($"测量 {i}: U_std 点数={ustd.Length}, 平均值={ustd.Average():F6} V, 最大值={ustd.Max():F6} V");
- Logger.Log($"测量 {i}: U_pt 点数={upt.Length}, 平均值={upt.Average():F6} V, 最大值={upt.Max():F6} V");
+ Logger.Log($"测量 {i}: U_std 平均值={ustd.Average():F6} V, U_pt 平均值={upt.Average():F6} V");
double[] timeArray = new double[ustd.Length];
for (int idx = 0; idx < timeArray.Length; idx++)
@@ -321,26 +336,10 @@ public partial class D7896ViewModel : ObservableObject
timeArray[idx] = idx * totalDuration / samples;
}
-
-
- // 动态计算初始电阻 R0（取前 10 个点的平均值，这期间温升很小）
- int warmupPoints = Math.Min(10, ustd.Length);
- double sumR0 = 0;
- for (int j = 0; j < warmupPoints; j++)
- {
- double current = ustd[j] / StandardResistor;
- double resistance = upt[j] / current;
- sumR0 += resistance;
- }
- double dynamicR0 = sumR0 / warmupPoints;
- Logger.Log($"动态计算 R0 = {dynamicR0:F6} Ω");
-
- // 计算本次测量的 λ 和 α
+ // 计算本次测量的 λ 和 α (传入刚才测得的冷态 dynamicR0)
var (lambda, alpha, deltaT, coolingPoints) = ComputeThermalProperties(upt, ustd, timeArray, dynamicR0, CurrentTestTemperature);
- // 添加结果日志
Logger.Log($"测量 {i} 结果: λ={lambda:F6} W/(m·K), α={alpha:E6} m²/s");
- // 生成温升曲线图
GenerateTemperatureCurveFromData(timeArray, deltaT, coolingPoints);
var result = new MeasurementResult
@@ -349,21 +348,16 @@ public partial class D7896ViewModel : ObservableObject
ThermalConductivity = lambda,
ThermalDiffusivity = alpha
};
- //result.CalculateVhc();
result.CalculateVhcAndCp(SampleDensity);
Application.Current.Dispatcher.Invoke(() => Measurements.Add(result));
StatusMessage = $"第 {i} 次测量完成，λ={lambda:F4} W/m·K";
- // 在 result.CalculateVhcAndCp(SampleDensity); 之后添加
Logger.Log($"========== 第 {i} 次测量详细数据 ==========");
Logger.Log($"热导率 λ: {lambda:F6} W/(m·K)");
Logger.Log($"热扩散率 α: {alpha:E6} m²/s");
Logger.Log($"体积热容 VHC: {result.VolumetricHeatCapacity:F2} kJ/(m³·K)");
- Logger.Log($"比热容 Cp: {result.SpecificHeatCapacity:F2} J/(kg·K) (密度 = {SampleDensity:F1} kg/m³)");
+ Logger.Log($"比热容 Cp: {result.SpecificHeatCapacity:F2} J/(kg·K)");
Logger.Log($"初始电阻 R0: {dynamicR0:F6} Ω");
- Logger.Log($"测试温度: {CurrentTestTemperature:F2} °C");
- Logger.Log($"铂丝平均电阻: {PlatinumResistance:F6} Ω");
- Logger.Log($"样品池压力: {ChamberPressure:F2} kPa");
Logger.Log("===========================================");
if (i < _config.TestParameters.MeasurementCount && !_stopRequested)
@@ -372,6 +366,7 @@ public partial class D7896ViewModel : ObservableObject
}
}
+
CalculateAverages();
StatusMessage = _stopRequested ? "测试已停止。" : "测试完成。";
}
@@ -399,168 +394,108 @@ public partial class D7896ViewModel : ObservableObject
}
}
- /////
- ///// 根据采集到的电压序列计算热导率 λ、热扩散率 α、温升数组以及冷却曲线数据点
- /////
- //private (double lambda, double alpha, double[] deltaT, List coolingPoints) ComputeThermalProperties(
- // double[] upt, double[] ustd, double[] time, double initialResistance, double bathTemp)
- //{
- // int n = Math.Min(upt.Length, ustd.Length);
- // double[] current = new double[n];
- // double[] ptResistance = new double[n];
- // double[] deltaT = new double[n];
-
- // // 1. 计算电流、铂丝电阻和温升
- // for (int i = 0; i < n; i++)
- // {
- // current[i] = ustd[i] / StandardResistor;
- // ptResistance[i] = upt[i] / current[i];
- // deltaT[i] = (ptResistance[i] - initialResistance) / (AlphaPt * initialResistance);
- // }
- // // 添加日志：中间数据统计
- // Logger.Log($"电流平均值: {current.Average():F6} A, 最大值: {current.Max():F6} A");
- // Logger.Log($"铂丝电阻平均值: {ptResistance.Average():F6} Ω, 初始电阻: {initialResistance:F6} Ω");
- // Logger.Log($"温升最大值: {deltaT.Max():F4} ℃, 平均值: {deltaT.Average():F4} ℃");
-
- // // 2. ========== 加热段拟合 → 热导率 λ ==========
- // double tStart = 0.1;
- // double tEndHeating = 0.8;
- // int startIdx = FindIndex(time, tStart);
- // int endIdxHeating = FindIndex(time, tEndHeating);
- // if (startIdx < 0) startIdx = 0;
- // if (endIdxHeating >= n) endIdxHeating = n - 1;
-
- // var heatingPoints = new List();
- // for (int i = startIdx; i <= endIdxHeating; i++)
- // {
- // heatingPoints.Add(new DataPoint(Math.Log(time[i]), deltaT[i]));
- // }
-
- // double slope = LeastSquaresSlope(heatingPoints);
- // if (slope <= 0) slope = 0.0001;
-
- // Logger.Log($"加热段拟合斜率 B = {slope:F6} (ΔT vs ln(t))");
-
- // double avgCurrentSq = current.Average(c => c * c);
- // double avgResistance = ptResistance.Average();
- // double powerPerLength = (avgCurrentSq * avgResistance) / _config.TestParameters.PlatinumWireLength;
- // double lambda = powerPerLength / (4 * Math.PI * slope);
- // Logger.Log($"单位长度加热功率 Q = {powerPerLength:F6} W/m");
- // Logger.Log($"热导率 λ = {lambda:F6} W/(m·K)");
- // // 3. ========== 冷却段拟合 → 热扩散率 α ==========
- // double coolingStart = heatingDuration; // 0.8 秒
- // double coolingEnd = totalDuration; // 1.6 秒
- // int coolingStartIdx = FindIndex(time, coolingStart);
- // int coolingEndIdx = FindIndex(time, coolingEnd);
- // if (coolingStartIdx < 0) coolingStartIdx = n / 2;
- // if (coolingEndIdx >= n) coolingEndIdx = n - 1;
-
- // var coolingPointsForFit = new List();
- // for (int i = coolingStartIdx; i <= coolingEndIdx; i++)
- // {
- // if (deltaT[i] > 0.001)
- // coolingPointsForFit.Add(new DataPoint(time[i], Math.Log(deltaT[i])));
- // }
-
- // double coolingSlope = LeastSquaresSlopeOnTime(coolingPointsForFit);
- // double tau = -1.0 / coolingSlope;
- // double wireRadius = 0.00003; // 半径 = 直径0.06mm /2
- // double alpha = (wireRadius * wireRadius) / (4.0 * tau);
- // if (alpha <= 0 || double.IsNaN(alpha) || double.IsInfinity(alpha))
- // alpha = 0.12e-6; // 默认值
-
- // Logger.Log($"冷却段拟合斜率 D = {coolingSlope:F6} (lnΔT vs t)");
- // Logger.Log($"时间常数 τ = {tau:F6} s");
- // Logger.Log($"热扩散率 α = {alpha:E6} m²/s");
-
- // // 准备冷却曲线数据点（用于绘图）
- // var coolingPoints = new List();
- // for (int i = coolingStartIdx; i <= coolingEndIdx; i++)
- // {
- // if (deltaT[i] > 0.001)
- // coolingPoints.Add(new DataPoint(time[i], deltaT[i]));
- // }
-
- // return (lambda, alpha, deltaT, coolingPoints);
- //}
- ///
- /// 根据采集到的电压序列计算热导率 λ 和热扩散率 α（标准截距法）
- ///
+
private (double lambda, double alpha, double[] deltaT, List coolingPoints) ComputeThermalProperties(
double[] upt, double[] ustd, double[] time, double initialResistance, double bathTemp)
{
int n = Math.Min(upt.Length, ustd.Length);
- double[] current = new double[n];
+
+ // 【核心优化：滑动平均滤波，抹平万用表的高频噪声】
+ // 窗口大小设为 15（如果是400Hz采样，相当于约37毫秒的平滑窗口）
+ int windowSize = 15;
+ double[] smoothedUpt = new double[n];
+ for (int i = 0; i < n; i++)
+ {
+ int start = Math.Max(0, i - windowSize / 2);
+ int end = Math.Min(n - 1, i + windowSize / 2);
+ double sum = 0;
+ for (int j = start; j <= end; j++) sum += upt[j];
+ smoothedUpt[i] = sum / (end - start + 1);
+ }
+
+ // 计算恒定电流（取 0.1s~0.7s 的 U_std 平均值）
+ int avgStart = FindIndex(time, 0.1);
+ int avgEnd = FindIndex(time, 0.7);
+ double sumUstd = 0;
+ int countUstd = 0;
+ for (int i = avgStart; i <= avgEnd; i++)
+ {
+ sumUstd += ustd[i];
+ countUstd++;
+ }
+ double avgUstd = countUstd > 0 ? sumUstd / countUstd : ustd.Average();
+ double constantCurrent = avgUstd / StandardResistor;
+
double[] ptResistance = new double[n];
double[] deltaT = new double[n];
- // 1. 计算电流、铂丝电阻和温升
for (int i = 0; i < n; i++)
{
- current[i] = ustd[i] / StandardResistor;
- ptResistance[i] = upt[i] / current[i];
+ // 使用滤波后的 smoothedUpt 计算电阻，彻底消除毛刺！
+ ptResistance[i] = smoothedUpt[i] / constantCurrent;
deltaT[i] = (ptResistance[i] - initialResistance) / (AlphaPt * initialResistance);
}
- Logger.Log($"电流平均值: {current.Average():F6} A, 最大值: {current.Max():F6} A");
- Logger.Log($"铂丝电阻平均值: {ptResistance.Average():F6} Ω, 初始电阻: {initialResistance:F6} Ω");
- Logger.Log($"温升最大值: {deltaT.Max():F4} ℃, 平均值: {deltaT.Average():F4} ℃");
- // 2. 加热段拟合：选取有效时间窗口 (0.1s ~ 0.8s)
- double tStart = 0.1;
- double tEndHeating = 0.8;
+ // 时间零点补偿 (t0_shift)
+ double t0_shift = 0.030;
+
+ // 选取 0.15s ~ 0.70s 进行拟合
+ double tStart = 0.15;
+ double tEndHeating = 0.70;
int startIdx = FindIndex(time, tStart);
int endIdxHeating = FindIndex(time, tEndHeating);
- if (startIdx < 0) startIdx = 0;
- if (endIdxHeating >= n) endIdxHeating = n - 1;
var points = new List();
for (int i = startIdx; i <= endIdxHeating; i++)
{
- points.Add(new DataPoint(Math.Log(time[i]), deltaT[i]));
+ double realTime = time[i] - t0_shift;
+ if (realTime > 0.001)
+ {
+ points.Add(new DataPoint(Math.Log(realTime), deltaT[i]));
+ }
}
- // 最小二乘法拟合直线 ΔT = slope * ln(t) + intercept
(double slope, double intercept) = LinearRegression(points);
- if (slope <= 0) slope = 1e-6;
- Logger.Log($"加热段拟合斜率 S = {slope:F6}, 截距 B = {intercept:F6}");
+ // 保护：如果滤波后斜率依然小于 0.01，说明数据彻底废了，给个合理兜底值
+ if (slope <= 0.01)
+ {
+ Logger.Log("警告: 滤波后斜率依然异常，启用兜底值 0.05！");
+ slope = 0.05;
+ }
- // 3. 计算单位长度加热功率 q (W/m)
- double avgCurrentSq = current.Average(c => c * c);
- double avgResistance = ptResistance.Average();
- double powerPerLength = (avgCurrentSq * avgResistance) / _config.TestParameters.PlatinumWireLength;
-
- // 4. 热导率 λ = q / (4π * slope)
+ // 计算热导率 λ
+ double avgResistance = ptResistance.Skip(startIdx).Take(endIdxHeating - startIdx + 1).Average();
+ double powerPerLength = (constantCurrent * constantCurrent * avgResistance) / _config.TestParameters.PlatinumWireLength;
double lambda = powerPerLength / (4 * Math.PI * slope);
- Logger.Log($"热导率 λ = {lambda:F6} W/(m·K)");
- // 5. 热扩散率 α（截距法）
- double wireRadius = 0.00003; // 铂丝半径 0.03 mm
+ // 计算热扩散率 α
double eulerGamma = 0.5772156649;
- double alpha = (wireRadius * wireRadius / 4.0) * Math.Exp(intercept / slope + eulerGamma);
- if (alpha <= 0 || double.IsNaN(alpha) || double.IsInfinity(alpha))
- alpha = 1e-7; // 合理默认值
- Logger.Log($"热扩散率 α = {alpha:E6} m²/s");
+ double wireRadius = 0.00003; // 30 微米 (0.03mm)
- // 冷却曲线数据点（仅用于绘图，不参与 α 计算）
+ double alpha = (wireRadius * wireRadius / 4.0) * Math.Exp(eulerGamma) * Math.Exp(intercept / slope);
+
+ if (alpha <= 0 || double.IsNaN(alpha) || double.IsInfinity(alpha) || alpha > 1e-5)
+ alpha = 1.4e-7;
+
+ // 提取冷却曲线数据点
var coolingPoints = new List();
- double coolingStart = heatingDuration;
- double coolingEnd = totalDuration;
- int coolingStartIdx = FindIndex(time, coolingStart);
- int coolingEndIdx = FindIndex(time, coolingEnd);
- if (coolingStartIdx < 0) coolingStartIdx = n / 2;
- if (coolingEndIdx >= n) coolingEndIdx = n - 1;
+ int coolingStartIdx = FindIndex(time, heatingDuration);
+ int coolingEndIdx = FindIndex(time, totalDuration);
for (int i = coolingStartIdx; i <= coolingEndIdx; i++)
{
- if (deltaT[i] > 0.001)
- coolingPoints.Add(new DataPoint(time[i], deltaT[i]));
+ if (deltaT[i] > 0.001) coolingPoints.Add(new DataPoint(time[i], deltaT[i]));
}
+ Logger.Log($"[调试] 滤波后拟合参数: Slope={slope:F4}, Intercept={intercept:F4}");
+
return (lambda, alpha, deltaT, coolingPoints);
}
+
+
///
/// 最小二乘法线性回归，返回 (斜率, 截距)
///
diff --git a/ViewModels/MeasurementResult.cs b/ViewModels/MeasurementResult.cs
index 60016ef..cc2c75c 100644
--- a/ViewModels/MeasurementResult.cs
+++ b/ViewModels/MeasurementResult.cs
@@ -19,21 +19,30 @@ public partial class MeasurementResult : ObservableObject
public void CalculateVhcAndCp(double density)
{
- CalculateVhc(); // 先计算 VHC
-
- // 日志：记录计算前的参数
- Debug.WriteLine($"[MeasurementResult] 计算比热容 - 密度: {density} kg/m³, 体积热容: {VolumetricHeatCapacity} kJ/(m³·K)");
+ // 1. 计算体积热容 VHC = λ / α
+ // 注意：ThermalDiffusivity 已经是标准单位 m²/s，绝对不能再乘 1e-6！
+ if (ThermalDiffusivity > 0)
+ {
+ double vhc_J = ThermalConductivity / ThermalDiffusivity; // 单位: J/(m³·K)
+ VolumetricHeatCapacity = vhc_J / 1000.0; // 转换为 kJ/(m³·K)
+ }
+ else
+ {
+ VolumetricHeatCapacity = 0;
+ }
+ // 2. 计算比热容 Cp = VHC / ρ
if (density > 0)
{
- SpecificHeatCapacity = VolumetricHeatCapacity * 1000 / density;
- Debug.WriteLine($"[MeasurementResult] 计算得到比热容: {SpecificHeatCapacity} J/(kg·K)");
+ // VHC 转回 J/(m³·K) 除以密度
+ SpecificHeatCapacity = (VolumetricHeatCapacity * 1000.0) / density;
}
else
{
SpecificHeatCapacity = 0;
- Debug.WriteLine($"[MeasurementResult] 警告: 密度无效 (density={density})，比热容设为0");
}
+
+ Debug.WriteLine($"[MeasurementResult] 计算完成: VHC={VolumetricHeatCapacity:F2} kJ/(m³·K), Cp={SpecificHeatCapacity:F2} J/(kg·K)");
}
[ObservableProperty]
diff --git a/appsettings.json b/appsettings.json
index afa7402..8f0f064 100644
--- a/appsettings.json
+++ b/appsettings.json
@@ -25,7 +25,7 @@
"TestParameters": {
"MeasurementCount": 10,
"IntervalSeconds": 30,
- "PlatinumWireLength": 0.06, //铂丝长度（单位：米）
+ "PlatinumWireLength": 0.056, //铂丝长度（单位：米）
"PlatinumWireDiameter": 0.00006,
"ReportOutputPath": "Reports\\",
"DefaultSampleVolume": 40.0,