OpenQBMM implements a set of quadrature-based moment methods to solve kinetic and generalized population balance equations. Specifically, the following capabilities are available:

**Solution of kinetic equations**`vdfTransportFoam`

solves for the moments of the velocity-based number density function for a pure particulate flow, not coupled to any other phase. The multi-variate velocity number density function is reconstructed using the hyperbolic quadrature method of moments. Collision effects are described by a run-time selectable collision model.`oneWayCoupledHyperbolicFoam`

solves for a one-way coupled particulate flow, in which the particulate flow is described using the hyperbolic quadrature method of moments, to incorporate non-equilibrium effects. Fluid and particles are coupled through the drag force.`diluteVdfTransportFoam`

solves for a two-way coupled particulate flow, where the particulate flow is described using the hyperbolic quadrature method of moments. Drag, lift and virtual mass are incorporated and their sub-model is selected at runtime.- The following collision models are available:
- BGK
- esBGK
- Boltzmann
- noCollisions (empty model to disable collisions)

**Solution of generalized population balance equation for multiphase flow applications**- The solvers listed above also support the solution of a generalized population balance equation, where the velocity of the particulate phase is described by the hyperbolic conditional quadrature method of moments and the size of the particle phase can evolve according to a population balance equation.
`polydisperseBubblyFoam`

is a solver which implements a specialized algorithm to model polydisperse gas-liquid systems, incorporating both the effect of polydispersity (the bubble size can evolve due to coalescence, breakup and other phenomena), and polycelerity (each bubble size has its own local velocity). This solver is suitable for applications to bubble columns, gas-liquid chemical reactors, and other flows where a disperse bubble phase interacting with a fluid.- The following coalescence frequency models are available:
- The following models are available for coalescence efficiency:
- Chester for bubbles with equal size
- CoulaloglouAndTavlarides based on film drainage and rupture times
- Lehr
- Luo
- PrinceAndBlanch

- The following breakup models are available:

`denseAGFoam`

is able of describing dense gas-particle flows, where the velocity distribution is modeled as anisotropic Gaussian. This solver is suitable for dense and moderately dense gas-particle flows in systems like fluidized beds and risers.