Update calculation.py

calculation.py

@@ -1,44 +1,73 @@
-import pandas as pd
-import numpy as np
-
-class SteamPipe:
-    def __init__(self, steam_flow, inlet_pressure, superheat, steam_temp, line_size, ambient_temp, ambient_velocity, insulation_material, cladding_material):
-        self.steam_flow = steam_flow
-        self.inlet_pressure = inlet_pressure
-        self.superheat = superheat
-        self.steam_temp = steam_temp
-        self.line_size = float(line_size)
-        self.ambient_temp = ambient_temp
-        self.ambient_velocity = ambient_velocity
-        self.insulation_material = insulation_material
-        self.cladding_material = cladding_material
-        
-        self.load_data()
-    
-    def load_data(self):
-        self.insulation_data = pd.read_csv("insulation_data.csv")
-        self.cladding_data = pd.read_csv("cladding_data.csv")
-        self.steam_properties = pd.read_csv("steam_properties.csv")
-    
-    def calculate_heat_loss(self):
-        # Placeholder heat loss calculation (to be replaced with actual formula)
-        return np.random.uniform(50, 200)  # Example random value
-    
-    def calculate_insulation_thickness(self):
-        # Placeholder insulation thickness calculation
-        return np.random.uniform(10, 100)  # Example random value
-    
-    def calculate_outlet_temperature(self, heat_loss):
-        # Placeholder outlet temperature calculation
-        delta_T = heat_loss * 0.01  # Example coefficient
-        return max(self.steam_temp - delta_T, self.ambient_temp)
-    
-    def calculate(self):
-        heat_loss = self.calculate_heat_loss()
-        required_thickness = self.calculate_insulation_thickness()
-        outlet_temp = self.calculate_outlet_temperature(heat_loss)
-        
-        return outlet_temp, required_thickness, heat_loss
-
-
-
+import pandas as pd
+import numpy as np
+import math
+
+class SteamPipe:
+    def __init__(self, steam_flow, inlet_pressure, superheat, steam_temp, line_size, ambient_temp, ambient_velocity, insulation_material, cladding_material, insulation_data, cladding_data, steam_properties, user_insulation_thickness=None):
+        self.steam_flow = steam_flow  # kg/hr
+        self.inlet_pressure = inlet_pressure  # kg/cm²g
+        self.superheat = superheat  # °C
+        self.steam_temp = steam_temp  # °C
+        self.line_size = float(line_size) * 0.0254  # Convert inch to meters (direct input, no lookup)
+        self.ambient_temp = ambient_temp  # °C
+        self.ambient_velocity = ambient_velocity  # m/s
+        self.insulation_material = insulation_material
+        self.cladding_material = cladding_material
+        
+        self.insulation_data = insulation_data
+        self.cladding_data = cladding_data
+        self.steam_properties = steam_properties
+        self.user_insulation_thickness = user_insulation_thickness  # User-defined insulation thickness
+    
+    def get_nearest_upper_value(self, df, column, value):
+        """Gets the nearest upper value from a given dataframe column."""
+        filtered_values = df[df[column] >= value]
+        return filtered_values[column].min() if not filtered_values.empty else df[column].max()
+    
+    def get_steam_property(self):
+        """Fetches steam property (enthalpy, specific heat, etc.) based on pressure."""
+        pressure = self.get_nearest_upper_value(self.steam_properties, 'Pressure', self.inlet_pressure)
+        row = self.steam_properties[self.steam_properties['Pressure'] == pressure]
+        if not row.empty:
+            return row.iloc[0]
+        else:
+            raise ValueError("Steam property not found for given pressure")
+
+    def calculate_heat_loss(self, insulation_thickness):
+        """Calculates heat loss per unit length using Fourier’s Law for cylindrical surfaces."""
+        k_insulation = self.get_nearest_upper_value(self.insulation_data, 'Thermal Conductivity', 0)
+        
+        r_inner = self.line_size / 2  # Inner radius (m)
+        r_outer = r_inner + insulation_thickness  # Outer radius (m)
+        
+        # Fourier’s Law for cylindrical coordinates
+        heat_loss = (2 * math.pi * (self.steam_temp - self.ambient_temp)) / (math.log(r_outer / r_inner) / k_insulation)
+        return heat_loss  # W/m
+    
+    def calculate_insulation_thickness(self):
+        """Determines required insulation thickness to minimize heat loss, or uses user-defined value."""
+        if self.user_insulation_thickness is not None:
+            return self.user_insulation_thickness * 0.001  # Convert mm to meters
+        thickness = self.get_nearest_upper_value(self.insulation_data[self.insulation_data['Material'] == self.insulation_material], 'Thickness', 0)
+        return thickness * 0.001  # Convert mm to meters
+    
+    def calculate_outlet_temperature(self, heat_loss):
+        """Estimates outlet temperature based on heat loss."""
+        steam_property = self.get_steam_property()
+        specific_heat = steam_property['Specific Heat']  # J/kgK
+        mass_flow_rate = self.steam_flow / 3600  # Convert kg/hr to kg/s
+        delta_T = heat_loss / (mass_flow_rate * specific_heat)
+        return max(self.steam_temp - delta_T, self.ambient_temp)
+    
+    def calculate(self):
+        insulation_thickness = self.calculate_insulation_thickness()
+        if np.isnan(insulation_thickness):
+            raise ValueError("Insulation thickness data not found.")
+        
+        heat_loss = self.calculate_heat_loss(insulation_thickness)
+        outlet_temp = self.calculate_outlet_temperature(heat_loss)
+        
+        return outlet_temp, insulation_thickness, heat_loss
+
+
+