Add Multicomponent Sips isotherm.

doc/interface/binding/multi_component_sips.rst

@@ -0,0 +1,84 @@
+.. _multi_component_sips_config:
+
+Multi Component Sips
+~~~~~~~~~~~~~~~~~~~~
+
+**Group /input/model/unit_XXX/adsorption – ADSORPTION_MODEL = MULTI_COMPONENT_SIPS**
+
+
+``IS_KINETIC``
+   Selects kinetic or quasi-stationary adsorption mode: 1 = kinetic, 0 =
+   quasi-stationary. If a single value is given, the mode is set for all
+   bound states. Otherwise, the adsorption mode is set for each bound
+   state separately.
+
+===================  =========================  =========================================
+**Type:** int        **Range:** {0,1}  		    **Length:** 1/NTOTALBND
+===================  =========================  =========================================
+
+``SIPS_KA``
+   Adsorption rate constants
+
+**Unit:** :math:`s^{-1}`
+
+===================  =========================  =========================================
+**Type:** double     **Range:** :math:`\ge 0`   **Length:** NCOMP
+===================  =========================  =========================================
+
+``SIPS_KD``
+   Desorption rate constants
+
+**Unit:** :math:`mol~m_{SP}^{-3}~s^{-1}`
+
+===================  =========================  ==================================
+**Type:** double     **Range:** :math:`\ge 0`   **Length:** NCOMP
+===================  =========================  ================================== 
+
+``SIPS_QMAX``
+   Maximum adsorption capacities
+
+**Unit:** :math:`mol~m_{SP}^{-3}`
+
+===================  =========================  ==================================
+**Type:** double     **Range:** :math:`\gt 0`   **Length:** NCOMP
+===================  =========================  ================================== 
+
+``SIPS_EXP``
+   Freundlich-type exponent
+
+===================  =========================  ==================================
+**Type:** double     **Range:** :math:`\gt 0`   **Length:** NCOMP
+===================  =========================  ================================== 
+
+``SIPS_REFC0``
+   Reference liquid phase concentration (optional, defaults to
+   :math:`1.0`)
+
+
+**Unit:** :math:`mol~m_{MP}^{-3}`
+
+===================  =========================  =========================================
+**Type:** double     **Range:** :math:`\gt 0`   **Length:** 1
+===================  =========================  =========================================
+
+``SIPS_REFQ``
+   Reference solid phase concentration (optional, defaults to
+   :math:`1.0`)
+
+
+**Unit:** :math:`mol~m_{SP}^{-3}`
+
+===================  =========================  =========================================
+**Type:** double     **Range:** :math:`\gt 0`   **Length:** 1
+===================  =========================  =========================================
+
+``SIPS_LINEAR_THRESHOLD``
+   Threshold for linearization. Originally, the liquid phase concentration
+   enters the adsorption rate via a power term. Below this threshold, a
+   quadratic approximation is used instead. This ensures numerical stability.
+
+**Unit:** :math:`mol~m_{MP}^{-3}`
+
+===================  =========================  =========================================
+**Type:** double     **Range:** :math:`\gt 0`   **Length:** 1
+===================  =========================  =========================================

doc/modelling/binding/index.rst

@@ -272,6 +272,11 @@ The models also differ in whether a mobile phase modifier (e.g., salt) is suppor
      - x
      - ✓
      - x
+   * - :ref:`multi_component_sips_model`
+     - ✓
+     - ×
+     - ✓
+     - ×
 
 
 .. toctree::

doc/modelling/binding/multi_component_sips.rst

@@ -0,0 +1,15 @@
+.. _multi_component_sips_model:
+
+Multi Component Sips
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+The Sips binding model is a combination of the :ref:`Freundlich<freundlich_ldf_model>` and the :ref:`Langmuir adsorption model<multi_component_langmuir_model>`.
+
+.. math::
+
+    \begin{aligned}
+        \frac{\mathrm{d} q_i}{\mathrm{d} t} = k_{a,i}\: \left( \frac{c_{p,i}}{ c_{\text{ref}} }\right)^{n_i}\: q_{\text{max},i} \left( 1 - \sum_{j=0}^{N_{\text{comp}} - 1} \frac{q_j}{q_{\text{max},j}} \right) - k_{d,i} \left( \frac{q_i}{q_{\text{ref}}} \right) && i = 0, \dots, N_{\text{comp}} - 1.
+    \end{aligned}
+
+
+For more information on model parameters required to define in CADET file format, see :ref:`multi_component_sips_config`.

src/libcadet/BindingModelFactory.cpp

@@ -45,6 +45,7 @@ namespace cadet
 			void registerBiLangmuirLDFModel(std::unordered_map<std::string, std::function<model::IBindingModel* ()>>& bindings);
 			void registerHICWaterOnHydrophobicSurfacesModel(std::unordered_map<std::string, std::function<model::IBindingModel*()>>& bindings);
 			void registerHICConstantWaterActivityModel(std::unordered_map<std::string, std::function<model::IBindingModel*()>>& bindings);
+			void registerSipsModel(std::unordered_map<std::string, std::function<model::IBindingModel*()>>& bindings);
 		}
 	}
 
@@ -75,6 +76,7 @@ namespace cadet
 		model::binding::registerBiLangmuirLDFModel(_bindingModels);
 		model::binding::registerHICWaterOnHydrophobicSurfacesModel(_bindingModels);
 		model::binding::registerHICConstantWaterActivityModel(_bindingModels);
+		model::binding::registerSipsModel(_bindingModels);
 		registerModel<model::SimplifiedMultiStateStericMassActionBinding>();
 	}
 

src/libcadet/CMakeLists.txt

@@ -100,6 +100,7 @@ set(LIBCADET_BINDINGMODEL_SOURCES
 	${CMAKE_SOURCE_DIR}/src/libcadet/model/binding/BiLangmuirLDFBinding.cpp
 	${CMAKE_SOURCE_DIR}/src/libcadet/model/binding/HICWaterOnHydrophobicSurfacesBinding.cpp
 	${CMAKE_SOURCE_DIR}/src/libcadet/model/binding/HICConstantWaterActivityBinding.cpp
+	${CMAKE_SOURCE_DIR}/src/libcadet/model/binding/SipsBinding.cpp
 )
 
 # LIBCADET_REACTIONMODEL_SOURCES holds all source files of reaction models
@@ -273,15 +274,15 @@ if (LAPACK_FOUND)
 	add_library(libcadet_static STATIC $<TARGET_OBJECTS:libcadet_object>)
 	set_target_properties(libcadet_static PROPERTIES OUTPUT_NAME cadet_static)
 	target_link_libraries(libcadet_static PUBLIC CADET::CompileOptions CADET::LibOptions PRIVATE CADET::AD libcadet_nonlinalg_static SUNDIALS::sundials_idas ${SUNDIALS_NVEC_TARGET} ${TBB_TARGET} ${EIGEN_TARGET})
-	
+
 	# ---------------------------------------------------
 	#   Build the shared library
 	# ---------------------------------------------------
 
 	add_library(libcadet_shared SHARED $<TARGET_OBJECTS:libcadet_object>)
 	set_target_properties(libcadet_shared PROPERTIES OUTPUT_NAME cadet)
 	target_link_libraries (libcadet_shared PUBLIC CADET::CompileOptions CADET::LibOptions PRIVATE CADET::AD libcadet_nonlinalg_static SUNDIALS::sundials_idas ${SUNDIALS_NVEC_TARGET} ${TBB_TARGET} ${EIGEN_TARGET})
-	
+
 	list(APPEND LIBCADET_TARGETS libcadet_nonlinalg_static libcadet_object libcadet_static libcadet_shared)
 
 	unset(LIB_LAPACK_DEFINE)