The field model JASMINE has been adapted to simulate the environmental conditions resulting from a vehicle fire that may occur in a channel tunnel shuttle wagon in transit. The calibration and verification of the model against a full scale car fire test initiated with seat ignition are then presented. An interesting feature of the modeling study was to simulate the interaction of the flows generated due to the fire with those due to the complex ventilation system of the shuttle wagon. It has been demonstrated that the model can reproduce satisfactorily both the thermal and chemical characteristics as observed in the test. The correspondence depends on selection of a realistic prescription for the fire growth curve and the ventilation system and by assuming that heat losses to the wagon walls and ceiling are properly accounted for.