Combustion tube tests’simulations become an increasingly important part in the design of projects aimed at the implementation of this recovery technique.Although simulations at the laboratory scale cannot be scaled directly to the field,they provide essential knowledge on how numerical modeling of physical and chemical phenomena that occur during combustion could be dealt with.The present paper reports simulations and history matching of a dry combustion tube test for a Brazilian heavy oil.Reaction model includes a coke generation reaction and three high temperature oxidation reactions of coke,heavy and light oil components. The history matching process is conducted in three stages.The first stage considers the matching of the combustion front velocity and fuel consumption,by altering the activation energy of the heavy fraction cracking reaction and the frequency factor of coke oxidation.In the second stage,production fluid rates and pressure drops are considered with the adjustment of the relative permeability curves and heat losses. In the third stage,the peak temperatures and produced gas composition are matchedby reviewing the kinetic parameters and the reaction stoichiometry. From the analysis of the laboratory data,a significant influence of the steam plateau in the production behavior is identified.It is observed that the initial volume of water present in the system is produced almost entirely before oil production begins.The oil bank approximates to the producer well once the initial water volume of the system has been produced.To better represent such occurrence,it is necessary to consider the relative permeability variation as a function of oil temperature,besides taking into account the radial heat losses in the system.This is shown as an efficient alternative to more adequately represent the fluid distribution along the combustion tube.Finally,it should be noted that the simulated results show an overall good representation of the experimental data.
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