{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# 231 蒸気圧縮冷凍サイクル\n",
"\n",
"## 読み込み"
]
},
{
"cell_type": "code",
"execution_count": 1,
"metadata": {},
"outputs": [],
"source": [
"import numpy as np\n",
"import pandas as pd\n",
"\n",
"import CoolProp.CoolProp as CP\n",
"\n",
"import matplotlib.pyplot as plt\n",
"%matplotlib inline\n",
"import warnings\n",
"warnings.filterwarnings(\"ignore\")"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## パラメータ定義"
]
},
{
"cell_type": "code",
"execution_count": 2,
"metadata": {},
"outputs": [],
"source": [
"WF = 'Ammonia'\n",
"\n",
"K = 273.16 # converter from degC to K\n",
"T_C = -30 +K #freezer air temperature deg C\n",
"DT_evap = 5 # evaporator approach temperature difference K\n",
"DT_sh = 4 # degree of supergeat K\n",
"T_H = 30 +K# Outdoor air temperature degC\n",
"DT_cond = 10 # condenser approach temperature difference K\n",
"DT_sc = 4 # degree of subcooling K\n",
"ETA_c = 0.78 # compressor efficiency\n",
"V_dot_disp = 16.52*1e-3 # compressor displacement m^3/sec\n",
"ETA_vol = 0.75 # compressor volumetric efficiency"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## データフレーム用意\n",
"\n",
"### Nomenclature\n",
"\n",
"| Symbol | Description | Unit |\n",
"| :--- | :---: | ---: |\n",
"| $T$ | Temperature | $K$ |\n",
"| $P$ | Pressure | $Pa$ |\n",
"| $s$ | Specific entropy | $J/kg-K$ |\n",
"| $v$ | Specific volume | $m^3/kg$ |\n",
"| $h$ | Specific enthalpy | $J/kg$ |\n",
"| $h_s$ | Specific enthalpy leaving reversible process | $J/kg$ |"
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {},
"outputs": [],
"source": [
"states = pd.DataFrame(columns=['T', 'P', 's', 'v', 'h', 'h_s'], index=list(range(1,4+1)))"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## State 4\n",
"\n",
"\\begin{align}\n",
"T_4 = T_H + \\Delta T_{cond} \\\\\n",
"T_{cond} = T_4 + \\Delta T_{sc}\n",
"\\end{align}"
]
},
{
"cell_type": "code",
"execution_count": 4,
"metadata": {},
"outputs": [],
"source": [
"states.loc[4, 'T'] = T_H + DT_cond\n",
"T_cond = states.loc[4, 'T'] + DT_sc\n",
"states.loc[4, 'P'] = CP.PropsSI('P', 'T', T_cond, 'Q', 0, WF)\n",
"states.loc[4, 's'] = CP.PropsSI('S', 'T', states.loc[4, 'T'], 'P', states.loc[4, 'P'], WF)\n",
"states.loc[4, 'h'] = CP.PropsSI('H', 'T', states.loc[4, 'T'], 'P', states.loc[4, 'P'], WF)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## State 2\n",
"\n",
"\\begin{align}\n",
"T_2 = T_C - \\Delta T_{evap} \\\\\n",
"T_{evap} = T_2 - \\Delta T_{sh}\n",
"\\end{align}"
]
},
{
"cell_type": "code",
"execution_count": 5,
"metadata": {},
"outputs": [],
"source": [
"states.loc[2, 'T'] = T_C - DT_evap\n",
"T_evap = states.loc[2, 'T'] - DT_sh\n",
"states.loc[2, 'P'] = CP.PropsSI('P', 'T', T_evap, 'Q', 1, WF)\n",
"states.loc[2, 's'] = CP.PropsSI('S', 'T', states.loc[2, 'T'], 'P', states.loc[2, 'P'], WF)\n",
"states.loc[2, 'h'] = CP.PropsSI('H', 'T', states.loc[2, 'T'], 'P', states.loc[2, 'P'], WF)\n",
"states.loc[2, 'v'] = 1/CP.PropsSI('D', 'T', states.loc[2, 'T'], 'P', states.loc[2, 'P'], WF)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## State 3\n",
"\n",
"\\begin{align}\n",
"\\frac{\\dot{W}_{s,c}}{\\dot{m}} = h_{s,3} - h_2 \\\\\n",
"\\frac{\\dot{W}_c}{\\dot{m}} = \\frac{1}{\\eta_c}\\frac{\\dot{W}_{s,c}}{\\dot{m}} \\\\\n",
"h_3 = h_2 + \\frac{\\dot{W}_c}{\\dot{m}}\n",
"\\end{align}"
]
},
{
"cell_type": "code",
"execution_count": 6,
"metadata": {},
"outputs": [],
"source": [
"states.loc[3, 'P'] = states.loc[4, 'P']\n",
"states.loc[3, 'h_s'] = CP.PropsSI('H', 'P', states.loc[3, 'P'], 'S', states.loc[2, 's'], WF)\n",
"W_dot_s_c_m_dot = states.loc[3, 'h_s'] - states.loc[2, 'h']\n",
"W_dot_c_m_dot = W_dot_s_c_m_dot/ETA_c\n",
"states.loc[3, 'h'] = states.loc[2, 'h'] + W_dot_c_m_dot\n",
"states.loc[3, 's'] = CP.PropsSI('S', 'P', states.loc[3, 'P'], 'H', states.loc[3, 'h'], WF)\n",
"states.loc[3, 'T'] = CP.PropsSI('T', 'P', states.loc[3, 'P'], 'H', states.loc[3, 'h'], WF)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## State 1\n",
"\n",
"\\begin{align}\n",
"P_1 = P_2 \\\\\n",
"h_1 = h_4\n",
"\\end{align}"
]
},
{
"cell_type": "code",
"execution_count": 7,
"metadata": {},
"outputs": [],
"source": [
"states.loc[1, 'P'] = states.loc[2, 'P']\n",
"states.loc[1, 'h'] = states.loc[4, 'h']\n",
"states.loc[1, 's'] = CP.PropsSI('S', 'P', states.loc[1, 'P'], 'H', states.loc[1, 'h'], WF)\n",
"states.loc[1, 'T'] = CP.PropsSI('T', 'P', states.loc[1, 'P'], 'H', states.loc[1, 'h'], WF)"
]
},
{
"cell_type": "code",
"execution_count": 8,
"metadata": {},
"outputs": [
{
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