def test_wet_bulb_temperature(self):
"""Wet bulb temperature from dry bulb temp and relative humidity."""
from psychrochart.equations import (
wet_bulb_temperature, relative_humidity_from_temps,
PRESSURE_STD_ATM_KPA)
from psychrochart.util import f_range
precision = 0.00001
p_atm = PRESSURE_STD_ATM_KPA
for dry_temp_c in f_range(-10, 60, 2.5):
for relative_humid in f_range(0.05, 1.0001, 0.05):
wet_temp_c = wet_bulb_temperature(
dry_temp_c, relative_humid,
p_atm_kpa=p_atm, precision=precision)
rh_calc = relative_humidity_from_temps(
dry_temp_c, wet_temp_c, p_atm_kpa=p_atm)
# print('wet_temp_c(dbt, rh): {:.3f} ºC ({:.1f} ºC, {:.1f} %)'
# .format(wet_temp_c, dry_temp_c, relative_humid * 100))
self.assertAlmostEqual(relative_humid, rh_calc, delta=0.01)
precision = 0.00001
p_atm = PRESSURE_STD_ATM_KPA * .75
for dry_temp_c in f_range(-5, 50, 5):
for relative_humid in f_range(0.05, 1.0001, 0.1):
wet_temp_c = wet_bulb_temperature(
dry_temp_c, relative_humid,
p_atm_kpa=p_atm, precision=precision)
rh_calc = relative_humidity_from_temps(
dry_temp_c, wet_temp_c, p_atm_kpa=p_atm)
# print('wet_temp_c(dbt, rh): {:.3f} ºC ({:.1f} ºC, {:.1f} %)'
# .format(wet_temp_c, dry_temp_c, relative_humid * 100))
self.assertAlmostEqual(relative_humid, rh_calc, delta=0.01)
def test_relative_humidity_from_temps(self):
from psychrochart.equations import (
relative_humidity_from_temps, PRESSURE_STD_ATM_KPA)
p_atm_kpa = PRESSURE_STD_ATM_KPA
for dry_temp_c, data in REL_HUMID_WITH_TEMP_WET_DELTA_TEMPS.items():
for delta_t, obj_rel_humid in data.items():
wet_temp_c = dry_temp_c - delta_t
rel_humid_calc = relative_humidity_from_temps(
dry_temp_c, wet_temp_c, p_atm_kpa=p_atm_kpa)
self.assertAlmostEqual(
round(100 * rel_humid_calc, 1), obj_rel_humid,
delta=0.65)
def _make_chart_data(self,
styles: Union[dict, str]=None,
zones_file: Union[dict, str]=None) -> None:
"""Generate the data to plot the psychrometric chart."""
# Get styling
config = load_config(styles)
self.d_config = config
self.temp_step = config['limits']['step_temp']
self.figure_params = config['figure']
self.dbt_min, self.dbt_max = config['limits']['range_temp_c']
self.w_min, self.w_max = config['limits']['range_humidity_g_kg']
self.chart_params = config['chart_params']
# Base pressure
if config['limits'].get('pressure_kpa') is not None:
self.p_atm_kpa = config['limits']['pressure_kpa']
elif config['limits'].get('altitude_m') is not None:
self.altitude_m = config['limits']['altitude_m']
self.p_atm_kpa = pressure_by_altitude(self.altitude_m)
# Dry bulb constant lines (vertical):
if self.chart_params["with_constant_dry_temp"]:
step = self.chart_params["constant_temp_step"]
style = config['constant_dry_temp']
temps_vl = f_range(self.dbt_min, self.dbt_max, step)
heights = [1000 * humidity_ratio(
saturation_pressure_water_vapor(t),
p_atm_kpa=self.p_atm_kpa) for t in temps_vl]
self.constant_dry_temp_data = PsychroCurves(
[PsychroCurve([t, t], [self.w_min, h], style,
type_curve='constant_dry_temp_data',
label=None, logger=self._logger)
for t, h in zip(temps_vl, heights)],
family_label=self.chart_params["constant_temp_label"])
# Absolute humidity constant lines (horizontal):
if self.chart_params["with_constant_humidity"]:
step = self.chart_params["constant_humid_step"]
style = config['constant_humidity']
ws_hl = f_range(self.w_min + step, self.w_max + step / 10, step)
dew_points = solve_curves_with_iteration(
'DEW POINT', [x / 1000 for x in ws_hl],
lambda x: dew_point_temperature(
water_vapor_pressure(
x, p_atm_kpa=self.p_atm_kpa)),
lambda x: humidity_ratio(
saturation_pressure_water_vapor(x),
p_atm_kpa=self.p_atm_kpa))
self.constant_humidity_data = PsychroCurves(
[PsychroCurve([t_dp, self.dbt_max], [w, w], style,
type_curve='constant_humidity_data',
label=None, logger=self._logger)
for w, t_dp in zip(ws_hl, dew_points)],
family_label=self.chart_params["constant_humid_label"])
# Constant relative humidity curves:
if self.chart_params["with_constant_rh"]:
rh_perc_values = self.chart_params["constant_rh_curves"]
rh_label_values = self.chart_params.get("constant_rh_labels", [])
label_loc = self.chart_params.get("constant_rh_labels_loc", .85)
style = config["constant_rh"]
temps_ct_rh, curves_ct_rh = _gen_list_curves_range_temps(
curve_constant_humidity_ratio,
self.dbt_min, self.dbt_max, self.temp_step,
rh_perc_values, p_atm_kpa=self.p_atm_kpa)
self.constant_rh_data = PsychroCurves(
[PsychroCurve(
temps_ct_rh, curve_ct_rh, style,
type_curve='constant_rh_data',
label_loc=label_loc, label='RH {:g} %'.format(rh)
if round(rh, 1) in rh_label_values else None,
logger=self._logger)
for rh, curve_ct_rh in zip(rh_perc_values, curves_ct_rh)],
family_label=self.chart_params["constant_rh_label"])
# Constant enthalpy lines:
if self.chart_params["with_constant_h"]:
step = self.chart_params["constant_h_step"]
start, end = self.chart_params["range_h"]
enthalpy_values = f_range(start, end, step)
h_label_values = self.chart_params.get("constant_h_labels", [])
label_loc = self.chart_params.get("constant_h_labels_loc", 1.)
style = config["constant_h"]
temps_max_constant_h = [
dry_temperature_for_enthalpy_of_moist_air(
self.w_min / 1000, h)
for h in enthalpy_values]
sat_points = solve_curves_with_iteration(
'ENTHALPHY', enthalpy_values,
lambda x: dry_temperature_for_enthalpy_of_moist_air(
self.w_min / 1000 + 0.1, x),
lambda x: enthalpy_moist_air(
x, saturation_pressure_water_vapor(x),
p_atm_kpa=self.p_atm_kpa))
self.constant_h_data = PsychroCurves(
[PsychroCurve(
[t_sat, t_max], [1000 * humidity_ratio(
saturation_pressure_water_vapor(t_sat),
self.p_atm_kpa), self.w_min], style,
type_curve='constant_h_data',
label_loc=label_loc, label='{:g} kJ/kg_da'.format(h)
if round(h, 3) in h_label_values else None,
logger=self._logger)
for t_sat, t_max, h in zip(
sat_points, temps_max_constant_h, enthalpy_values)],
family_label=self.chart_params["constant_h_label"])
# Constant specific volume lines:
if self.chart_params["with_constant_v"]:
step = self.chart_params["constant_v_step"]
start, end = self.chart_params["range_vol_m3_kg"]
vol_values = f_range(start, end, step)
vol_label_values = self.chart_params.get("constant_v_labels", [])
label_loc = self.chart_params.get("constant_v_labels_loc", 1.)
style = config["constant_v"]
temps_max_constant_v = [
dry_temperature_for_specific_volume_of_moist_air(
0, specific_vol, p_atm_kpa=self.p_atm_kpa)
for specific_vol in vol_values]
sat_points = solve_curves_with_iteration(
'CONSTANT VOLUME', vol_values,
lambda x: dry_temperature_for_specific_volume_of_moist_air(
0, x, p_atm_kpa=self.p_atm_kpa),
lambda x: specific_volume(
x, saturation_pressure_water_vapor(x),
p_atm_kpa=self.p_atm_kpa))
self.constant_v_data = PsychroCurves(
[PsychroCurve(
[t_sat, t_max], [1000 * humidity_ratio(
saturation_pressure_water_vapor(t_sat),
self.p_atm_kpa), 0],
style, type_curve='constant_v_data',
label_loc=label_loc, label='{:g} m3/kg_da'.format(vol)
if round(vol, 3) in vol_label_values else None,
logger=self._logger)
for t_sat, t_max, vol in zip(
sat_points, temps_max_constant_v, vol_values)],
family_label=self.chart_params["constant_v_label"])
# Constant wet bulb temperature lines:
if self.chart_params["with_constant_wet_temp"]:
step = self.chart_params["constant_wet_temp_step"]
start, end = self.chart_params["range_wet_temp"]
wbt_values = f_range(start, end, step)
wbt_label_values = self.chart_params.get(
"constant_wet_temp_labels", [])
label_loc = self.chart_params.get(
"constant_wet_temp_labels_loc", .05)
style = config["constant_wet_temp"]
w_max_constant_wbt = [humidity_ratio(
saturation_pressure_water_vapor(wbt), self.p_atm_kpa)
for wbt in wbt_values]
self.constant_wbt_data = PsychroCurves(
[PsychroCurve(
[wbt, self.dbt_max],
[1000 * w_max,
1000 * humidity_ratio(
saturation_pressure_water_vapor(self.dbt_max)
* relative_humidity_from_temps(
self.dbt_max, wbt, p_atm_kpa=self.p_atm_kpa),
p_atm_kpa=self.p_atm_kpa)], style,
type_curve='constant_wbt_data',
label_loc=label_loc, label='{:g} °C'.format(wbt)
if wbt in wbt_label_values else None, logger=self._logger)
for wbt, w_max in zip(wbt_values, w_max_constant_wbt)],
family_label=self.chart_params["constant_wet_temp_label"])
# Saturation line:
if True:
sat_style = config["saturation"]
temps_sat_line, w_sat_line = _gen_list_curves_range_temps(
curve_constant_humidity_ratio,
self.dbt_min, self.dbt_max, self.temp_step, [100],
p_atm_kpa=self.p_atm_kpa)
self.saturation = PsychroCurves(
[PsychroCurve(
temps_sat_line, w_sat_line[0], sat_style,
type_curve='saturation', logger=self._logger)])
# Zones
if self.chart_params["with_zones"] or zones_file is not None:
self.append_zones(zones_file)
