Exemplo n.º 1
0
def test_control_valve():
    from fluids.control_valve import cavitation_index, FF_critical_pressure_ratio_l, is_choked_turbulent_l, is_choked_turbulent_g, Reynolds_valve, loss_coefficient_piping, Reynolds_factor
    CI = cavitation_index(1E6, 8E5, 2E5)
    assert_close(CI, 4.0)

    FF = FF_critical_pressure_ratio_l(70100.0, 22120000.0)
    assert_close(FF, 0.9442375225233299)

    F = is_choked_turbulent_l(460.0, 680.0, 70.1, 0.9442375225233299, 0.9)
    assert not F
    T = is_choked_turbulent_l(460.0, 680.0, 70.1, 0.9442375225233299, 0.6)
    assert T

    with pytest.raises(Exception):
        is_choked_turbulent_l(460.0, 680.0, 70.1, 0.9442375225233299)

    # Example 4, compressible flow - small flow trim sized for gas flow:
    assert False == is_choked_turbulent_g(0.536, 1.193, 0.8)
    # Custom example
    assert True == is_choked_turbulent_g(0.9, 1.193, 0.7)

    with pytest.raises(Exception):
        is_choked_turbulent_g(0.544, 0.929)

    Rev = Reynolds_valve(3.26e-07, 360, 100.0, 0.6, 0.98, 238.05817216710483)
    assert_close(Rev, 6596953.826574914)

    Rev = Reynolds_valve(3.26e-07, 360, 150.0, 0.9, 0.46, 164.9954763704956)
    assert_close(Rev, 2967024.346783506)

    K = loss_coefficient_piping(0.05, 0.08, 0.1)
    assert_close(K, 0.6580810546875)

    ### Reynolds factor (laminar)
    # In Example 4, compressible flow with small flow trim sized for gas flow
    # (Cv in the problem was converted to Kv here to make FR match with N32, N2):
    f = Reynolds_factor(FL=0.98, C=0.015483, d=15., Rev=1202., full_trim=False)
    assert_close(f, 0.7148753122302025)

    # Custom, same as above but with full trim:
    f = Reynolds_factor(FL=0.98, C=0.015483, d=15., Rev=1202., full_trim=True)
    assert_close(f, 0.9875328782172637)

    # Example 4 with Rev < 10:
    f = Reynolds_factor(FL=0.98, C=0.015483, d=15., Rev=8., full_trim=False)
    assert_close(f, 0.08339546213461975)

    # Same, with full_trim
    f = Reynolds_factor(FL=0.98, C=0.015483, d=15., Rev=8., full_trim=True)
    assert_close(f, 43.619397389803986)
Exemplo n.º 2
0
def test_control_valve():
    from fluids.control_valve import cavitation_index, FF_critical_pressure_ratio_l, is_choked_turbulent_l, is_choked_turbulent_g, Reynolds_valve, loss_coefficient_piping, Reynolds_factor
    CI = cavitation_index(1E6, 8E5, 2E5)
    assert_allclose(CI, 4.0)

    FF = FF_critical_pressure_ratio_l(70100.0, 22120000.0)
    assert_allclose(FF, 0.9442375225233299)

    F = is_choked_turbulent_l(460.0, 680.0, 70.1, 0.9442375225233299, 0.9)
    T = is_choked_turbulent_l(460.0, 680.0, 70.1, 0.9442375225233299, 0.6)
    assert_allclose([False, True], [F, T])

    with pytest.raises(Exception):
        is_choked_turbulent_l(460.0, 680.0, 70.1, 0.9442375225233299)

    # Example 4, compressible flow - small flow trim sized for gas flow:
    assert False == is_choked_turbulent_g(0.536, 1.193, 0.8)
    # Custom example
    assert True == is_choked_turbulent_g(0.9, 1.193, 0.7)

    with pytest.raises(Exception):
        is_choked_turbulent_g(0.544, 0.929)

    Rev = Reynolds_valve(3.26e-07, 360, 100.0, 0.6, 0.98, 238.05817216710483)
    assert_allclose(Rev, 6596953.826574914)

    Rev = Reynolds_valve(3.26e-07, 360, 150.0, 0.9, 0.46, 164.9954763704956)
    assert_allclose(Rev, 2967024.346783506)

    K = loss_coefficient_piping(0.05, 0.08, 0.1)
    assert_allclose(K, 0.6580810546875)

    ### Reynolds factor (laminar)
    # In Example 4, compressible flow with small flow trim sized for gas flow
    # (Cv in the problem was converted to Kv here to make FR match with N32, N2):
    f = Reynolds_factor(FL=0.98, C=0.015483, d=15., Rev=1202., full_trim=False)
    assert_allclose(f, 0.7148753122302025)

    # Custom, same as above but with full trim:
    f = Reynolds_factor(FL=0.98, C=0.015483, d=15., Rev=1202., full_trim=True)
    assert_allclose(f, 0.9875328782172637)

    # Example 4 with Rev < 10:
    f = Reynolds_factor(FL=0.98, C=0.015483, d=15., Rev=8., full_trim=False)
    assert_allclose(f, 0.08339546213461975)

    # Same, with full_trim
    f = Reynolds_factor(FL=0.98, C=0.015483, d=15., Rev=8., full_trim=True)
    assert_allclose(f, 43.619397389803986)