The work presents the investigation results of the influence on supersonic oxygen- hydrogen mixture flow by the injected flow into it generated by a detonation tube installed in the supersonic channel wall. The goal of this work is to study the processes of chemical reaction initiation and flow reconstruction under such influence. The mathematical model of the combustion initiation in the experimental setup is developed within a continuous medium on the model-based of a chemically nonequilibrium single-temperature gas. For the combustion reaction of the oxygen-hydrogen mixture, the following main reagents were selected: H2O, OH, O, H, H2, O2, HO2, H2O2 and O3. The combustion kinetic scheme involving these reagents contains 27 reactions. The numerical solution of the equation initial system was found using a third-order noncentral difference scheme. The parameters of the flow initiating combustion were determined from the system of one-dimensional conservation laws for a detonation wave in a detonation tube.