Add product_yield feature for Reaction objects

[yoelcortes]

Hi @joyxyz1994, @yalinli2,

This pull request adds a new product_yield method for reaction objects to be able to get and set the net yield for a specific product by either weight or mol. The tests I added should help explain how it works:

import thermosteam as tmo
tmo.settings.set_thermo(['H2O', 'H2', 'O2'], cache=True)
single_phase_reaction = reaction = tmo.Reaction(
    '2H2O -> 2H2 + O2', reactant='H2O',
    correct_atomic_balance=True, X=0.5
)
multi_phase_reaction = reaction = tmo.Reaction(
    'H2O,l -> H2,g + O2,g', reactant='H2O',
    correct_atomic_balance=True, X=0.7
)

# Test product_yield with and without multiple phases
assert_allclose(single_phase_reaction.product_yield('O2'), 0.25)
assert_allclose(multi_phase_reaction.product_yield('O2'), 0.35)
assert_allclose(single_phase_reaction.product_yield('H2'), 0.5)
assert_allclose(multi_phase_reaction.product_yield('H2'), 0.7)
assert_allclose(single_phase_reaction.product_yield('O2', basis='wt'), 0.44405082796381734)
assert_allclose(multi_phase_reaction.product_yield('O2', basis='wt'), 0.6216711591493442)

# Test product_yield setter with and without multiple phases
single_phase_reaction.product_yield('O2', product_yield=0.1)
multi_phase_reaction.product_yield('O2', product_yield=0.1)
assert_allclose(single_phase_reaction.product_yield('O2'), 0.1)
assert_allclose(multi_phase_reaction.product_yield('O2'), 0.1)

single_phase_reaction.product_yield('H2', product_yield=0.1)
multi_phase_reaction.product_yield('H2', product_yield=0.1)
assert_allclose(single_phase_reaction.product_yield('H2'), 0.1)
assert_allclose(multi_phase_reaction.product_yield('H2'), 0.1)

single_phase_reaction.product_yield('O2', basis='wt', product_yield=0.1)
multi_phase_reaction.product_yield('O2', basis='wt', product_yield=0.1)
assert_allclose(single_phase_reaction.product_yield('O2', basis='wt'), 0.1)
assert_allclose(multi_phase_reaction.product_yield('O2', basis='wt'), 0.1)

Thanks!

[yalinli2]

thanks @yoelcortes ! I added more details to the doc - feel free to update if needed, thanks!

[yoelcortes]

Awesome, thanks a bunch!