Spaces:
Sleeping
Sleeping
File size: 4,074 Bytes
87d8d0b 747c020 87d8d0b 747c020 87d8d0b 747c020 87d8d0b 747c020 87d8d0b 747c020 87d8d0b 747c020 87d8d0b 3203f03 87d8d0b 3203f03 87d8d0b |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 |
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, 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.user_insulation_thickness = user_insulation_thickness # User-defined insulation thickness
# Load data from CSV files
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 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 (Kg/cm²g)', self.inlet_pressure)
row = self.steam_properties[self.steam_properties['Pressure (Kg/cm²g)'] == pressure]
if not row.empty:
return row.iloc[0]
else:
raise ValueError("Steam property not found for given pressure")
def get_cladding_emissivity(self):
"""Fetches emissivity of selected cladding material."""
row = self.cladding_data[self.cladding_data['Material'] == self.cladding_material]
if not row.empty:
return row['Emissivity'].values[0]
else:
raise ValueError("Cladding material not found")
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[self.insulation_data['Material'] == self.insulation_material], 'Thermal_Conductivity (W/mK)', 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 (Cp) (kJ/kg·K)'] # kJ/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, required_thickness):
heat_loss = self.calculate_heat_loss(required_thickness)
outlet_temp = self.calculate_outlet_temperature(heat_loss)
return outlet_temp, heat_loss
|