KIVA (software)
Encyclopedia
KIVA is a family of Fortran
-based Computational Fluid Dynamics
software developed by Los Alamos National Laboratory
(LANL). The software predicts complex fuel and air flows as well as ignition
, combustion
, and pollutant-formation processes in engines. The KIVA models have been used to understand combustion chemistry processes, such as auto-ignition of fuels, and to optimize diesel engine
s for high efficiency and low emissions. General Motors
has used KIVA in the development of direct-injection, stratified charge gasoline engines as well as the fast burn, homogeneous-charge gasoline engine. Cummins
reduced development time and cost by 10%–15% using KIVA to develop its high-efficiency 2007 ISB 6.7-L diesel engine that was able to meet 2010 emission standards in 2007. At the same time, the company realized a more robust design and improved fuel economy while meeting all environmental and customer constraints.
in the 1940s. When the nation found itself in the midst of the first energy crisis in the 1970s, this core Laboratory capability transformed into KIVA, an internal combustion engine
modeling tool designed to help make automotive engines more fuel-efficient and cleaner-burning. A "kiva
" is actually a round Pueblo
ceremonial chamber that is set underground and entered from above by means of a ladder through its roof; drawing on LANL's southwestern heritage, an analogy is made with the typical engine cylinder in which the entrance and exit of gases is achieved through valves set in the cylinder.
The first public release of KIVA was made in 1985 through the National Energy Software Center (NESC) at Argonne National Laboratory
, which served at the time as the official distribution hub for Department of Energy
-sponsored software. Distribution of KIVA continued through the Energy Science and Technology Software Center (ESTSC) in Oak Ridge
, Tennessee
until 2008, when distribution of multiple versions of KIVA returned to LANL's Technology Transfer
Division (TT). KIVA is used by hundreds of institutions worldwide
, including the Big Three U.S. auto makers , Cummins
, Caterpillar
, and various federal laboratories.
is heavily dependent upon engine efficiency
, which in turn depends to a large degree on how fuel is burned within the cylinders of the engine. Higher in-cylinder pressures and temperatures lead to increased fuel economy, but they also create more difficulty in controlling the combustion
process. Poorly controlled and incomplete combustion can cause higher levels of emissions and lower engine
efficiencies.
In order to optimize combustion processes, engine designers have traditionally undertaken manual engine modifications, conducted testing, and analyzed the results. This iterative process is painstakingly slow, costly, and does not lend itself to identifying the optimal engine design specifications. In response to these problems, Los Alamos National Laboratory scientists developed KIVA, an advanced computational fluid dynamics
(CFD) modeling code that accurately simulates the in-cylinder processes of engines.
KIVA, a transient, three-dimensional, multiphase
, multicomponent
code for the analysis of chemically reacting flows with sprays has been under development at LANL for decades. The code uses an Arbitrary Lagrangian Eulerian (ALE) methodology on a staggered grid
, and discretizes space using the finite volume method
. The code uses an implicit time-advancement with the exception of the advective terms that are cast in an explicit but second-order monotonicity
-preserving manner. Also, the convection
calculations can be subcycled in the desired regions to avoid restricting the time step due to Courant
conditions.
KIVA’s functionality extends from low speeds to supersonic
flows for both laminar
and turbulent regimes. Transport and chemical reactions for an arbitrary number of species and their chemical reactions is provided. A stochastic
particle method is used to calculate evaporating liquid sprays, including the effects of droplet collisions, agglomeration
, and aerodynamic breakups.
Although specifically designed for simulating internal combustion engines, the modularity of the code facilitates easy modifications for solving a variety of hydrodynamics problems involving chemical reactions. The versatility and range of features have made KIVA programs attractive to a variety of non-engine applications as well; these range from convection towers to modeling silicon dioxide
condensation
in high pressure oxidation chambers. Other applications have included the analysis of flows in automotive catalytic converters, power plant smokestack cleaning, pyrolytic
treatment of biomass
, design of fire suppression systems, Pulsed Detonation Engines
(PDEs), stationary burners, aerosol dispersion, and design of heating, ventilation, and air conditioning
systems. The code has found a widespread application in the automotive industry.
Excellence in Technology Transfer Award-winning KIVA3 (1993), extended to model vertical or canted valves in the cylinder head of a gasoline or diesel engine. KIVA3, in turn, was based on the earlier KIVA2 (1989) and used the same numerical solution procedure and solved the same types of equations.
KIVA-3V uses a block-structured mesh with connectivity defined through indirect addressing. The departure from a single rectangular structure in logical space allows complex geometries to be modeled with significantly greater efficiency because large regions of deactivated cells are no longer necessary. Cell-face boundary conditions permit greater flexibility and simplification in the application of boundary conditions. KIVA-3V also contains a number of significant improvements over its predecessors. New features enhanced the robustness, efficiency, and usefulness of the overall program for engine modeling. Automatic restart of the cycle with a reduced timestep in case of iteration limit or temperature overflow effectively reduced code crashes. A new option provided automatic deactivation of a port region when it is closed from the cylinder and reactivation when it communicates with the cylinder. Extensions to the particle-based liquid wall film model made the model more complete and a split injection option was also added. A new subroutine monitors the liquid and gaseous fuel phases and energy balance data and emissions are monitored and printed. In addition, new features were added to the LANL-developed grid generator, K3PREP, and the KIVA graphics post processor, K3POST.
s, pyramids, and tetrahedra. However, the numerical accuracy diminishes when the grid is not composed of hexahedra. KIVA-4 was developed to work with the many geometries accommodated within KIVA-3V, which includes 2D axisymmetric, 2D planar, 3D axisymmetric sector geometries, and full 3D geometries. KIVA-4 also features a multicomponent fuel evaporation algorithm. Many of the numerical algorithms in KIVA-3V generalize properly to unstructured meshes; however, fundamental changes were needed in the solution of the pressure equation and the fluxing of momentum. In addition, KIVA-4 loops over cell faces to compute diffusion
terms.
(MPI). On August 9, 2011, LANL honored the authors of KIVA-4mpi with the Distinguished Copyright Award for demonstrating a breadth of commercial applications, potential to create economic value, and the highest level of technical excellence.
Fortran
Fortran is a general-purpose, procedural, imperative programming language that is especially suited to numeric computation and scientific computing...
-based Computational Fluid Dynamics
Computational fluid dynamics
Computational fluid dynamics, usually abbreviated as CFD, is a branch of fluid mechanics that uses numerical methods and algorithms to solve and analyze problems that involve fluid flows. Computers are used to perform the calculations required to simulate the interaction of liquids and gases with...
software developed by Los Alamos National Laboratory
Los Alamos National Laboratory
Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...
(LANL). The software predicts complex fuel and air flows as well as ignition
Ignition
Ignition may refer to:*Making fire*CombustionEvents* Ignition , a Burning Man regional event held in Montreal, QuebecIn Media* Ignition , a top-down racing game for PC published in 1997...
, combustion
Combustion
Combustion or burning is the sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat and conversion of chemical species. The release of heat can result in the production of light in the form of either glowing or a flame...
, and pollutant-formation processes in engines. The KIVA models have been used to understand combustion chemistry processes, such as auto-ignition of fuels, and to optimize diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
s for high efficiency and low emissions. General Motors
General Motors
General Motors Company , commonly known as GM, formerly incorporated as General Motors Corporation, is an American multinational automotive corporation headquartered in Detroit, Michigan and the world's second-largest automaker in 2010...
has used KIVA in the development of direct-injection, stratified charge gasoline engines as well as the fast burn, homogeneous-charge gasoline engine. Cummins
Cummins
Cummins Inc. is a Fortune 500 corporation that designs, manufactures, distributes and services engines and related technologies, including fuel systems, controls, air handling, filtration, emission control and electrical power generation systems...
reduced development time and cost by 10%–15% using KIVA to develop its high-efficiency 2007 ISB 6.7-L diesel engine that was able to meet 2010 emission standards in 2007. At the same time, the company realized a more robust design and improved fuel economy while meeting all environmental and customer constraints.
History
LANL's Computational Fluid Dynamics expertise hails from the very beginning of the Manhattan ProjectManhattan Project
The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...
in the 1940s. When the nation found itself in the midst of the first energy crisis in the 1970s, this core Laboratory capability transformed into KIVA, an internal combustion engine
Internal combustion engine
The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...
modeling tool designed to help make automotive engines more fuel-efficient and cleaner-burning. A "kiva
Kiva
A kiva is a room used by modern Puebloans for religious rituals, many of them associated with the kachina belief system. Among the modern Hopi and most other Pueblo peoples, kivas are square-walled and underground, and are used for spiritual ceremonies....
" is actually a round Pueblo
Pueblo
Pueblo is a term used to describe modern communities of Native Americans in the Southwestern United States of America. The first Spanish explorers of the Southwest used this term to describe the communities housed in apartment-like structures built of stone, adobe mud, and other local material...
ceremonial chamber that is set underground and entered from above by means of a ladder through its roof; drawing on LANL's southwestern heritage, an analogy is made with the typical engine cylinder in which the entrance and exit of gases is achieved through valves set in the cylinder.
The first public release of KIVA was made in 1985 through the National Energy Software Center (NESC) at Argonne National Laboratory
Argonne National Laboratory
Argonne National Laboratory is the first science and engineering research national laboratory in the United States, receiving this designation on July 1, 1946. It is the largest national laboratory by size and scope in the Midwest...
, which served at the time as the official distribution hub for Department of Energy
United States Department of Energy
The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...
-sponsored software. Distribution of KIVA continued through the Energy Science and Technology Software Center (ESTSC) in Oak Ridge
Oak Ridge, Tennessee
Oak Ridge is a city in Anderson and Roane counties in the eastern part of the U.S. state of Tennessee, about west of Knoxville. Oak Ridge's population was 27,387 at the 2000 census...
, Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...
until 2008, when distribution of multiple versions of KIVA returned to LANL's Technology Transfer
Technology transfer
Technology Transfer, also called Transfer of Technology and Technology Commercialisation, is the process of skill transferring, knowledge, technologies, methods of manufacturing, samples of manufacturing and facilities among governments or universities and other institutions to ensure that...
Division (TT). KIVA is used by hundreds of institutions worldwide
World
World is a common name for the whole of human civilization, specifically human experience, history, or the human condition in general, worldwide, i.e. anywhere on Earth....
, including the Big Three U.S. auto makers , Cummins
Cummins
Cummins Inc. is a Fortune 500 corporation that designs, manufactures, distributes and services engines and related technologies, including fuel systems, controls, air handling, filtration, emission control and electrical power generation systems...
, Caterpillar
Caterpillar
Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...
, and various federal laboratories.
Overview
Fuel economyFuel economy in automobiles
Fuel usage in automobiles refers to the fuel efficiency relationship between distance traveled by an automobile and the amount of fuel consumed....
is heavily dependent upon engine efficiency
Engine efficiency
Engine efficiency of thermal engines is the relationship between the total energy contained in the fuel, and the amount of energy used to perform useful work...
, which in turn depends to a large degree on how fuel is burned within the cylinders of the engine. Higher in-cylinder pressures and temperatures lead to increased fuel economy, but they also create more difficulty in controlling the combustion
Combustion
Combustion or burning is the sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat and conversion of chemical species. The release of heat can result in the production of light in the form of either glowing or a flame...
process. Poorly controlled and incomplete combustion can cause higher levels of emissions and lower engine
Engine
An engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines burn a fuel to create heat which is then used to create motion...
efficiencies.
In order to optimize combustion processes, engine designers have traditionally undertaken manual engine modifications, conducted testing, and analyzed the results. This iterative process is painstakingly slow, costly, and does not lend itself to identifying the optimal engine design specifications. In response to these problems, Los Alamos National Laboratory scientists developed KIVA, an advanced computational fluid dynamics
Computational fluid dynamics
Computational fluid dynamics, usually abbreviated as CFD, is a branch of fluid mechanics that uses numerical methods and algorithms to solve and analyze problems that involve fluid flows. Computers are used to perform the calculations required to simulate the interaction of liquids and gases with...
(CFD) modeling code that accurately simulates the in-cylinder processes of engines.
KIVA, a transient, three-dimensional, multiphase
Multiphase flow
In fluid mechanics, multiphase flow is a generalisation of the modelling used in two-phase flow to cases where the two phases are not chemically related or where more than two phases are present In fluid mechanics, multiphase flow is a generalisation of the modelling used in two-phase flow to...
, multicomponent
Multi-component reaction
In chemistry, a multi-component reaction , sometimes referred to as a "Multi-component Assembly Process" , is a chemical reaction where three or more compounds react to form a single product...
code for the analysis of chemically reacting flows with sprays has been under development at LANL for decades. The code uses an Arbitrary Lagrangian Eulerian (ALE) methodology on a staggered grid
Lattice graph
The terms lattice graph, mesh graph, or grid graph refer to a number of categories of graphs whose drawing corresponds to some grid/mesh/lattice, i.e., its vertices correspond to the nodes of the mesh and its edges correspond to the ties between the nodes.-Square grid graph:A common type of a...
, and discretizes space using the finite volume method
Finite volume method
The finite volume method is a method for representing and evaluating partial differential equations in the form of algebraic equations [LeVeque, 2002; Toro, 1999]....
. The code uses an implicit time-advancement with the exception of the advective terms that are cast in an explicit but second-order monotonicity
Monotonic function
In mathematics, a monotonic function is a function that preserves the given order. This concept first arose in calculus, and was later generalized to the more abstract setting of order theory....
-preserving manner. Also, the convection
Convection
Convection is the movement of molecules within fluids and rheids. It cannot take place in solids, since neither bulk current flows nor significant diffusion can take place in solids....
calculations can be subcycled in the desired regions to avoid restricting the time step due to Courant
Courant–Friedrichs–Lewy condition
In mathematics, the Courant–Friedrichs–Lewy condition is a necessary condition for convergence while solving certain partial differential equations numerically by the method of finite differences. It arises when explicit time-marching schemes are used for the numerical solution...
conditions.
KIVA’s functionality extends from low speeds to supersonic
Supersonic
Supersonic speed is a rate of travel of an object that exceeds the speed of sound . For objects traveling in dry air of a temperature of 20 °C this speed is approximately 343 m/s, 1,125 ft/s, 768 mph or 1,235 km/h. Speeds greater than five times the speed of sound are often...
flows for both laminar
Laminar flow
Laminar flow, sometimes known as streamline flow, occurs when a fluid flows in parallel layers, with no disruption between the layers. At low velocities the fluid tends to flow without lateral mixing, and adjacent layers slide past one another like playing cards. There are no cross currents...
and turbulent regimes. Transport and chemical reactions for an arbitrary number of species and their chemical reactions is provided. A stochastic
Stochastic
Stochastic refers to systems whose behaviour is intrinsically non-deterministic. A stochastic process is one whose behavior is non-deterministic, in that a system's subsequent state is determined both by the process's predictable actions and by a random element. However, according to M. Kac and E...
particle method is used to calculate evaporating liquid sprays, including the effects of droplet collisions, agglomeration
Agglomeration
In the study of human settlements, an urban agglomeration is an extended city or town area comprising the built-up area of a central place and any suburbs linked by continuous urban area. In France, INSEE the French Statistical Institute, translate it as "Unité urbaine" which means continuous...
, and aerodynamic breakups.
Although specifically designed for simulating internal combustion engines, the modularity of the code facilitates easy modifications for solving a variety of hydrodynamics problems involving chemical reactions. The versatility and range of features have made KIVA programs attractive to a variety of non-engine applications as well; these range from convection towers to modeling silicon dioxide
Silicon dioxide
The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with the chemical formula '. It has been known for its hardness since antiquity...
condensation
Condensation
Condensation is the change of the physical state of matter from gaseous phase into liquid phase, and is the reverse of vaporization. When the transition happens from the gaseous phase into the solid phase directly, the change is called deposition....
in high pressure oxidation chambers. Other applications have included the analysis of flows in automotive catalytic converters, power plant smokestack cleaning, pyrolytic
Pyrolysis
Pyrolysis is a thermochemical decomposition of organic material at elevated temperatures without the participation of oxygen. It involves the simultaneous change of chemical composition and physical phase, and is irreversible...
treatment of biomass
Biomass
Biomass, as a renewable energy source, is biological material from living, or recently living organisms. As an energy source, biomass can either be used directly, or converted into other energy products such as biofuel....
, design of fire suppression systems, Pulsed Detonation Engines
Pulse detonation engine
A pulse detonation engine, or "PDE", is a type of propulsion system that uses detonation waves to combust the fuel and oxidizer mixture. The engine is pulsed because the mixture must be renewed in the combustion chamber between each detonation wave initiated by an ignition source. Theoretically, a...
(PDEs), stationary burners, aerosol dispersion, and design of heating, ventilation, and air conditioning
Air conditioning
An air conditioner is a home appliance, system, or mechanism designed to dehumidify and extract heat from an area. The cooling is done using a simple refrigeration cycle...
systems. The code has found a widespread application in the automotive industry.
KIVA-3V
KIVA-3V is the most mature version of KIVA still maintained and distributed through LANL; it is an improved version of the earlier Federal Laboratory ConsortiumFederal Laboratory Consortium
The Federal Laboratory Consortium for Technology Transfer is a U.S.-based nationwide network of federal laboratories that provides the forum to develop strategies and opportunities to help transfer laboratory mission technologies into commercial products for the global marketplace.The FLC was...
Excellence in Technology Transfer Award-winning KIVA3 (1993), extended to model vertical or canted valves in the cylinder head of a gasoline or diesel engine. KIVA3, in turn, was based on the earlier KIVA2 (1989) and used the same numerical solution procedure and solved the same types of equations.
KIVA-3V uses a block-structured mesh with connectivity defined through indirect addressing. The departure from a single rectangular structure in logical space allows complex geometries to be modeled with significantly greater efficiency because large regions of deactivated cells are no longer necessary. Cell-face boundary conditions permit greater flexibility and simplification in the application of boundary conditions. KIVA-3V also contains a number of significant improvements over its predecessors. New features enhanced the robustness, efficiency, and usefulness of the overall program for engine modeling. Automatic restart of the cycle with a reduced timestep in case of iteration limit or temperature overflow effectively reduced code crashes. A new option provided automatic deactivation of a port region when it is closed from the cylinder and reactivation when it communicates with the cylinder. Extensions to the particle-based liquid wall film model made the model more complete and a split injection option was also added. A new subroutine monitors the liquid and gaseous fuel phases and energy balance data and emissions are monitored and printed. In addition, new features were added to the LANL-developed grid generator, K3PREP, and the KIVA graphics post processor, K3POST.
KIVA-4
KIVA-4 is maintained and distributed through LANL. While KIVA-4 maintains the full generality of KIVA-3V, it adds the capability of computing with unstructured grids. Unstructured grids can be generated more easily than structured grids for complex geometries. The unstructured grids may be composed of a variety of elements including hexahedra, prismPrism (geometry)
In geometry, a prism is a polyhedron with an n-sided polygonal base, a translated copy , and n other faces joining corresponding sides of the two bases. All cross-sections parallel to the base faces are the same. Prisms are named for their base, so a prism with a pentagonal base is called a...
s, pyramids, and tetrahedra. However, the numerical accuracy diminishes when the grid is not composed of hexahedra. KIVA-4 was developed to work with the many geometries accommodated within KIVA-3V, which includes 2D axisymmetric, 2D planar, 3D axisymmetric sector geometries, and full 3D geometries. KIVA-4 also features a multicomponent fuel evaporation algorithm. Many of the numerical algorithms in KIVA-3V generalize properly to unstructured meshes; however, fundamental changes were needed in the solution of the pressure equation and the fluxing of momentum. In addition, KIVA-4 loops over cell faces to compute diffusion
Diffusion
Molecular diffusion, often called simply diffusion, is the thermal motion of all particles at temperatures above absolute zero. The rate of this movement is a function of temperature, viscosity of the fluid and the size of the particles...
terms.
KIVA-4mpi
Recently, LANL researchers developed KIVA-4mpi, a parallel version of KIVA-4, and the most advanced version of KIVA maintained and distributed by LANL. KIVA-4mpi also solves chemically reacting, turbulent, multi-phase viscous flows, but does this on multiple computer processors with a distributed computational domain (grid). KIVA-4mpi internal combustion engine modeling capabilities are the same as that of KIVA-4, and are based on the KIVA-4 unstructured grid code. The software is well suited for modeling internal combustion engines on multiple processors using the message passing interfaceMessage Passing Interface
Message Passing Interface is a standardized and portable message-passing system designed by a group of researchers from academia and industry to function on a wide variety of parallel computers...
(MPI). On August 9, 2011, LANL honored the authors of KIVA-4mpi with the Distinguished Copyright Award for demonstrating a breadth of commercial applications, potential to create economic value, and the highest level of technical excellence.
KIVA Videos
External links
- KIVA-4 User’s Manual
- KIVA-3V manual (0.4MB, searchable within READER.)
- KIVA-3V manual (1.5MB, searchable within READER.)
- KIVA-3 manual (2.2 MB, searchable within READER.)
- KIVA-II manual (9.0MB, scanned document, not searchable.)
- Los Alamos National Laboratory’s T-3 Group
- Los Alamos National Laboratory Technology Transfer Division