fixed dry-air molar mass (number vs. mass weighting), l_tri as a computed derived value; bib-script enhancements; Trivia.K2C and C2K; introducing XFAIL for R&S example on Windows (to be addressed in subsequent PR) (#1507)

Co-authored-by: Sylwester Arabas <[email protected]>

Author: AgnieszkaZaba

.github/workflows/tests.yml

@@ -267,8 +267,12 @@ jobs:
           pvpython --version
           pvpython -c "from paraview import simple"
 
-      - env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        run: |
+      - run: |
           python -m pytest --durations=10 -v -p no:unraisableexception -We tests/examples_tests/test_tests_completeness.py
-          python -m pytest --durations=10 -v -p no:unraisableexception -We tests/examples_tests/test_run* --suite ${{ matrix.test-suite }}
+
+       # TODO #1207
+      - if: startsWith(matrix.platform, 'windows-')
+        run: python -m pytest --durations=10 -v -p no:unraisableexception -We tests/examples_tests/test_run* -k "not Rozanski_and_Sonntag_1982" --suite ${{ matrix.test-suite }}
+
+      - if: ( ! startsWith(matrix.platform, 'windows-') )
+        run: python -m pytest --durations=10 -v -p no:unraisableexception -We tests/examples_tests/test_run* --suite ${{ matrix.test-suite }}

PySDM/physics/constants_defaults.py

@@ -6,7 +6,6 @@
 """
 
 import numpy as np
-from chempy import Substance
 from scipy import constants as sci
 
 from .constants import (  # pylint: disable=unused-import
@@ -29,14 +28,11 @@
 )
 from .trivia import Trivia
 
-# https://physics.nist.gov/cgi-bin/Star/compos.pl?matno=104
-# TODO #1507
-Md = (
-    0.755267 * Substance.from_formula("N2").mass * si.gram / si.mole
-    + 0.231781 * Substance.from_formula("O2").mass * si.gram / si.mole
-    + 0.012827 * Substance.from_formula("Ar").mass * si.gram / si.mole
-    + 0.000124 * Substance.from_formula("C").mass * si.gram / si.mole
-)
+Md = 28.966 * si.g / si.mole
+"""
+A "twenty-first century" value of dry-air molar mass recommended in
+[Gatley et al. 2008](https://doi.org/10.1080/10789669.2008.10391032)
+"""
 
 VSMOW_R_2H = 155.76 * PPM
 """
@@ -194,8 +190,8 @@
 [Murphy & Koop 2005](https://doi.org/10.1256/qj.04.94) """
 T_tri = 273.16 * si.kelvin
 """ 〃 """
-
-l_tri = 2.5e6 * si.joule / si.kilogram
+L_tri = 45051.0 * si.joule / si.mol
+""" 〃 """
 
 l_l19_a = 0.167 * si.dimensionless
 """ [Seinfeld and Pandis](https://archive.org/details/0237-pdf-atmospheric-chemistry-and-physics-2nd-ed-j.-seinfeld-s.-pandis-wiley-2006-ww)
@@ -687,3 +683,5 @@ def compute_derived_values(c: dict):
     c["water_molar_volume"] = c["Mv"] / c["rho_w"]
     c["rho_STP"] = c["p_STP"] / c["Rd"] / c["T_STP"]
     c["H_u"] = c["M"] / c["p_STP"]
+
+    c["l_tri"] = c["L_tri"] / c["Mv"]

PySDM/physics/trivia.py

@@ -138,6 +138,14 @@ def air_schmidt_number(dynamic_viscosity, diffusivity, density):
     def sqrt_re_times_cbrt_sc(const, Re, Sc):
         return np.power(Re, const.ONE_HALF) * np.power(Sc, const.ONE_THIRD)
 
+    @staticmethod
+    def K2C(const, TK):
+        return TK - const.T0
+
+    @staticmethod
+    def C2K(const, TC):
+        return TC + const.T0
+
     @staticmethod
     def poissonian_avoidance_function(r, dt):
         """cumulative probability of zero events occurring within time `dt`

docs/bibliography.json

@@ -719,6 +719,11 @@
     "title": "Vapor Pressure Formulation for Water in Range 0 to 100 °C. A Revision",
     "label": "Wexler 1976 (J. Res. NBS A Phys. Ch. 80A)"
   },
+  "https://doi.org/10.1080/10789669.2008.10391032": {
+    "usages": ["PySDM/physics/constants_defaults.py"],
+    "title": "A Twenty-First Century Molar Mass for Dry Air",
+    "label": "Gatley et al. 2008 (HVAC&R Res. 14)"
+  },
   "https://archive.org/details/shortcourseinclo0000roge_m3k2": {
     "usages": ["PySDM/physics/constants_defaults.py", "PySDM/physics/terminal_velocity/rogers_yau.py"],
     "title": "A short course in clouds physics",

examples/PySDM_examples/Rozanski_and_Sonntag_1982/multibox.py

@@ -46,6 +46,7 @@ def __init__(
 
     def advance_parcel_vars(self):
         """explicit Euler integration of isotope-ratio time derivative"""
+        assert self.delta_liquid_water_mixing_ratio >= 0
         self._recalculate_temperature_pressure_relative_humidity(self._tmp)
 
         alpha_old = {}
@@ -67,7 +68,6 @@ def advance_parcel_vars(self):
                 d_n_vapour=-self.delta_liquid_water_mixing_ratio / self.dt,
                 n_liquid=self.autoconversion_mixrat_threshold,  # TODO #1207
             )
-            assert dRv__dt[isotope] <= 0
 
         super().advance_parcel_vars()
 

tests/smoke_tests/parcel_d/rozanski_and_sonntag_1982/test_figs_4_5_6.py

@@ -1,6 +1,7 @@
 """tests ensuring values on plots match those in the paper"""
 
 from pathlib import Path
+import platform
 
 import numpy as np
 import pytest
@@ -20,6 +21,7 @@ def variables_fixture():
     )
 
 
+@pytest.mark.xfail(platform.system() == "Windows", strict=True, reason="TODO #1207")
 class TestFigs456:
     @staticmethod
     def test_fig_5_vapour_asymptote(variables):

tests/unit_tests/backends/test_physics_methods.py

@@ -35,7 +35,7 @@ def test_temperature_pressure_rh(backend_instance):
         # Assert
         assert 282 * si.K < T.amin() < 283 * si.K
         assert 810 * si.hPa < p.amin() < 830 * si.hPa
-        assert 1.12 < RH.amin() < 1.13
+        assert 1.10 < RH.amin() < 1.11
 
     @staticmethod
     @pytest.mark.parametrize("variant", ("LiquidSpheres", "MixedPhaseSpheres"))

tests/unit_tests/physics/test_drop_growth.py

@@ -5,7 +5,8 @@
 import numpy as np
 
 from PySDM.formulae import _choices, Formulae
-from PySDM.physics import drop_growth, constants_defaults, si, in_unit
+from PySDM.physics import drop_growth
+from PySDM.physics.constants import PER_CENT, si, in_unit
 from PySDM.physics.dimensional_analysis import DimensionalAnalysis
 
 
@@ -39,7 +40,7 @@ def test_mason_1971_vs_1951_difference_vs_temperature(plot=False):
         """checks the relative difference between Mason's 1951 and 1971 formulae
         for a range of temperatures"""
         # arrange
-        temperatures = constants_defaults.T0 + np.linspace(-10, 40) * si.K
+        temperatures = Formulae().trivia.C2K(np.linspace(-10, 40) * si.K)
         papers = ("Mason1951", "Mason1971")
 
         # act
@@ -60,7 +61,7 @@ def test_mason_1971_vs_1951_difference_vs_temperature(plot=False):
         relative_error = r_dr_dt["Mason1971"] / r_dr_dt["Mason1951"] - 1
 
         # plot
-        pyplot.plot(temperatures, in_unit(relative_error, constants_defaults.PER_CENT))
+        pyplot.plot(temperatures, in_unit(relative_error, PER_CENT))
         pyplot.title("")
         pyplot.xlabel("temperature [K]")
         pyplot.ylabel("r dr/dt relative difference (1971 vs. 1951) [%]")

tests/unit_tests/physics/test_latent_heat.py

@@ -12,7 +12,6 @@ def test_latent_heats(plot=False):
     formulae = {k: Formulae(latent_heat=k) for k in ("Kirchhoff", "Lowe2019")}
     const = Formulae().constants
     temperature = np.linspace(-20, 20) + const.T_tri
-
     # Plot
     pyplot.axhline(const.l_tri, label="triple point", color="red")
     pyplot.axvline(const.T_tri, color="red")

tests/unit_tests/physics/test_trivia.py

@@ -89,3 +89,27 @@ def test_poissonian_avoidance_function():
 
             # Assert
             assert prob.check(si.dimensionless)
+
+    @staticmethod
+    def test_kelvin_to_celsius():
+        # arrange
+        formulae = Formulae()
+        temperature_in_kelvin = 44
+
+        # act
+        temperature_in_celsius = formulae.trivia.K2C(temperature_in_kelvin)
+
+        # assert
+        assert temperature_in_celsius == temperature_in_kelvin - 273.15
+
+    @staticmethod
+    def test_celsius_to_kelvin():
+        # arrange
+        formulae = Formulae()
+        temperature_in_celsius = 666
+
+        # act
+        temperature_in_kelvin = formulae.trivia.C2K(temperature_in_celsius)
+
+        # assert
+        assert temperature_in_kelvin == temperature_in_celsius + 273.15