Detailed combustion analysis

Dacolt combustion tools can be used to investigate elementary combustion processes in detail. The ability to determine basic reacting characteristics for a given chemical composition is of great importance in practical engineering that deals with improving system performance, optimising fuel economy and reducing pollutant emissions.

The image on the right illustrates a two-stage ignition process for n-heptane fuel, with the normalised profiles of temperature and fuel and oxygen mole fractions.

Parametric studies

Dacolt combustion tools can also be used to do parametric investigations, by varying one parameter at the time. For example, the effect of initial temperature on auto-ignition take can be investigated, or the equilibrium composition for various levels of equivalence ratio of a given fuel and oxidiser.

The image on the right illustrates the equilibrium temperature as function of mixture fraction, for methane fuel and an oxidiser consisting in standard air with various levels of oxygen addition.

CFD look-up tables

Complex chemistry effects play a predominant role in practical turbulent combustion applications. The most commonly used manner to include such effects in CFD modelling is to pre-compute the chemistry and to store the relevant data in a multi-dimensional database or look-up table. This look-up table is read by the CFD code at the start of a simulation and the data is interpolated during the simulation, as illustrated by the image on the right.

To create a look-up table, hundreds to tens of thousands individual chemistry simulations must be performed. Setting-up such a simulation is greatly simplified with the expert input module of Dacolt tools. The execution time is kept to a minimum as Dacolt combustion tools make full use of the power of Cloud Computing, by distributing the simulations across a large number of CPUs. 

Contact us for more information on the usage of Dacolt combustion tools.