Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for fluid blob tracking. One of the methods includes identifying, by a computer system, a connected fluid phase region in a flow simulation. The method includes tracking, by the computer system, the connected fluid phase region over a first timeframe and a second timeframe. The method also includes determining, by the computer system, movement of the connected fluid phase region from the first timeframe to the second timeframe based on the tracking.

Abstract: A computer-implemented method for simulating flow and acoustic interaction of a fluid with a porous medium includes simulating activity of a fluid in a first volume adjoining a second volume, the activity of the fluid in the first volume being simulated so as to model movement of elements within the first volume and using a first model having a first set of parameters, simulating activity of the fluid in the second volume occupied by the porous medium, the activity in the second volume being simulated so as to model movement of elements within the second volume and using a second model having a second set of parameters, and simulating movement of elements between the first volume and the second volume at an interface between the first volume and the second volume.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for processing data in a data processing system to identify candidate modifications to physical features of a mechanical device. One of the methods includes converting a representation of the mechanical device into a representation of surface elements. The method includes that based on the representation of the surface elements, computing an effect to evaluation criteria of each of a design variable. The method includes converting the design variables and the computed effect into component vectors. The method includes computing a composite design vector for the evaluation criteria using the component vectors, with the composite design vector comprising a combination of design variable settings to improve the evaluation criteria, and specifying a vector in a design variable space. The method also includes generating a physical modification specification for the mechanical device based on the composite design vector.

Abstract: A method comprising: simulating, in a lattice velocity set, movement of particles in a volume of fluid, with the movement causing collision among the particles; based on the simulated movement, determining relative particle velocity of a particle at a particular location within the volume, with the relative particle velocity being a difference between (i) an absolute velocity of the particle at the particular location within the volume and measured under zero flow of the volume, and (ii) a mean velocity of one or more of the particles at the particular location within the volume; and determining, based on the relative particle velocity, a non-equilibrium post-collide distribution function of a specified order that is representative of the collision.

Abstract: A method for simulating a fluid flow that includes a laminar to turbulent boundary layer transition on a computer, the method comprising: for one or more locations on or near a boundary surface: performing a first calculation where a local boundary layer is taken to be a laminar boundary layer; performing a second calculation where the local boundary layer is taken to be a turbulent boundary layer; comparing a result from the first calculation to a result from the second calculation; and based on the comparing, selecting the result of the first calculation or the result of the second calculation; and inputting the selected result for the one or more locations into a simulation of activity of a fluid in a volume comprising the boundary surface.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for fluid blob tracking. One of the methods includes identifying, by a computer system, a connected fluid phase region in a flow simulation. The method includes tracking, by the computer system, the connected fluid phase region over a first timeframe and a second timeframe. The method also includes determining, by the computer system, movement of the connected fluid phase region from the first timeframe to the second timeframe based on the tracking.

Abstract: A fluid flow is simulated by causing a computer to perform operations on data stored in the memory to compute at least one eddy of a fluid flow at a first scale and perform operations to compute at least one eddy of the fluid flow at both the first scale and a second scale. The second scale is a finer scale than the first scale, and the computation of the at least one eddy of the fluid flow at the second scale is constrained by results of the computation of the at least one eddy of the fluid flow at the first scale.

Abstract: A computer-implemented method for simulating flow and acoustic interaction of a fluid with a porous medium includes simulating activity of a fluid in a first volume adjoining a second occupied by a porous medium, the activity of the fluid in the first volume being simulated so as to model movement of elements within the first volume and using a first model having a first set of parameters, simulating activity of the fluid in the second volume occupied by the porous medium, the activity in the second volume being simulated so as to model movement of elements within the second volume and using a second model having a second set of parameters and differing from the first model in a way that accounts for flow and acoustic properties of the porous medium, and simulating movement of elements between the first volume and the second volume at an interface between the first volume and the second volume.

Abstract: A fluid flow is simulated by causing a computer to perform operations on data stored in the memory to compute at least one eddy of a fluid flow at a first scale and perform operations to compute at least one eddy of the fluid flow at both the first scale and a second scale. The second scale is a finer scale than the first scale, and the computation of the at least one eddy of the fluid flow at the second scale is constrained by results of the computation of the at least one eddy of the fluid flow at the first scale.

Abstract: This description relates to computer simulation of physical processes, such as computer simulation of multi-species flow through porous media including the determination/estimation of relative permeabilities for the multi-species flow through the porous media.

Abstract: A computer-implemented method for simulating fluid flow using a lattice Boltzmann (LB) approach that includes assigning values for the wall shear stress on a per-facet (e.g., per-surfel) basis based on whether the fluid flow is laminar or turbulent is described herein.

Abstract: A fluid flow is simulated by causing a computer to perform operations on data stored in the memory to compute at least one eddy of a fluid flow at a first scale and perform operations to compute at least one eddy of the fluid flow at both the first scale and a second scale. The second scale is a finer scale than the first scale, and the computation of the at least one eddy of the fluid flow at the second scale is constrained by results of the computation of the at least one eddy of the fluid flow at the first scale.

Abstract: A computer-implemented method for simulating fluid flow using a lattice Boltzmann (LB) approach and for solving scalar transport equations is described herein. In addition to the lattice Boltzmann functions for fluid flow, a second set of distribution functions is introduced for transport scalars.

Abstract: Simulating a physical process includes storing, in a computer-accessible memory, state vectors for voxels, where the state vectors correspond to a model and include entries that correspond to particular momentum states of possible momentum states at a voxel. Interaction operations are performed on the state vectors. The interaction operations model interactions between elements of different momentum states according to the model. Move operations performed on the state vectors reflect movement of elements to new voxels according to the model. The model is adapted to simulate a high-Knudsen number flow that has a Knudsen number greater than 0.1.

Abstract: Simulating a physical process includes storing, in a computer-accessible memory, state vectors for voxels, where the state vectors correspond to a model and include entries that correspond to particular momentum states of possible momentum states at a voxel. Interaction operations are performed on the state vectors. The interaction operations model interactions between elements of different momentum states according to the model. Move operations performed on the state vectors reflect movement of elements to new voxels according to the model. The model is adapted to simulate a high-Knudsen number flow that has a Knudsen number greater than 0.1.

Abstract: Simulating a physical process includes storing, in a computer-accessible memory, state vectors for voxels, where the state vectors correspond to a model and include entries that correspond to particular momentum states of possible momentum states at a voxel. Interaction operations are performed on the state vectors. The interaction operations model interactions between elements of different momentum states according to the model. Move operations performed on the state vectors reflect movement of elements to new voxels according to the model. The model is adapted to simulate a high-Knudsen number flow that has a Knudsen number greater than 0.1.

Abstract: Simulating a physical process includes storing, in a computer-accessible memory, state vectors for voxels, where the state vectors correspond to a model and include entries that correspond to particular momentum states of possible momentum states at a voxel. Interaction operations are performed on the state vectors. The interaction operations model interactions between elements of different momentum states according to the model. Move operations performed on the state vectors reflect movement of elements to new voxels according to the model. The model is adapted to simulate a high-Knudsen number flow that has a Knudsen number greater than 0.1.

Abstract: Simulating a physical process includes storing, in a computer-accessible memory, state vectors for voxels, where the state vectors correspond to a model and include entries that correspond to particular momentum states of possible momentum states at a voxel. Interaction operations are performed on the state vectors. The interaction operations model interactions between elements of different momentum states according to the model. Move operations performed on the state vectors reflect movement of elements to new voxels according to the model. The model is adapted to simulate a high-Knudsen number flow that has a Knudsen number greater than 0.1.

Abstract: Simulating a physical process includes storing, in a computer-accessible memory, state vectors for voxels, where the state vectors correspond to a model and include entries that correspond to particular momentum states of possible momentum states at a voxel. Interaction operations are performed on the state vectors. The interaction operations model interactions between elements of different momentum states according to the model. Move operations performed on the state vectors reflect movement of elements to new voxels according to the model. The model is adapted to simulate a high-Knudsen number flow that has a Knudsen number greater than 0.1.

Abstract: A fluid flow is simulated by causing a computer to perform operations on data stored in the memory to compute at least one eddy of a fluid flow at a first scale and perform operations to compute at least one eddy of the fluid flow at both the first scale and a second scale. The second scale is a finer scale than the first scale, and the computation of the at least one eddy of the fluid flow at the second scale is constrained by results of the computation of the at least one eddy of the fluid flow at the first scale.