1 Abstract This work illustrates the possibility of applying the numerical calculation to illustrate physical phenomena and to calculate the values of airflow characteristics in the axial compressor of the GTD-350 engine. For the purpose of the study two types of simulation software were used: Solid Works Flow Simulation [3] and Ansys Fluent [4]. A 3D model of the compressor was prepared based on the measurements in SolidWorks. This model was then tested in simulations in SolidWorks and Ansys followed by an analysis of the simulation results. 1 Introduction Progress in the numerical and computational methods allowed to precisely model flow inside turbomachines. Thus, incorporation of the numerical simulations at the initial stage of the design process enabled to reduce the number of manufactured prototypes and shorten the design time. Nowadays, the Computational Fluid Dynamics (CFD) is used also for optimisation of the performance of turbomachinery parts like jet engine compressors and turbines [5-12]. The main goal of the article is to examine the feasibility of methodology based on Computer Aided Engineering and reverse engineering for investigation of flow inside of compressor of popular turboshaft engine GTD-350. The analysis with use of two commercial CFD solvers was performed in order to provide comparative analysis. The results of the simulations are in good agreement with characteristic provided by the engine manufacturer. The outcome of the work proved that methodology combining reverse engineering and CFD simulations can be used for investigations of flow inside turboshaft engines modules. 2 GTD-350 Engine Engine GTD-350 is a low-power turboprop engine (Fig 1) and constitutes a part of the twin- engine drive unit of the helicopter Mi-2. It was designed at the beginning of the 60s of the XX century by an engineer, Siergiej Piotrowicz Izotow of Klimov designing office. Starting from 1966 it was manufactured in the Mechanical Plant, WSK Rzeszów, by the agreement between Poland and Russia. Fig. 1. GTD-350 engine This engine is characterised by a special construction with reversed airflow. The compressor consist of axial and centrifugal compressor. The axial compressor consists of seven compression stages with stationary flow ducts. It is driven by a single-stage free turbine. The turbine consisting of two stages with stationary flow ducts drives necessary aggregates and the helicopter rotor [2]. A model of the axial compressor GTD-350 was created in SolidWorks using technical drawings, cross-sections of the blade profiles and basic measurement devices. This model consists of COMPARATIVE ANALYSIS OF AIR FLOW IN THE COMPRESSOR OF THE GTD-350 ENGINE Robert SZCZEPANIAK*, Robert BĄBEL*, Wit STRYCZNIEWICZ** *Air Force Academy Poland, **Institute of Aviation Poland 1 Corresponding Author E-mail: robert.szczepaniak@o2.pl Keywords: GTD-350 Engine, CFD, Internal flow, Ansys, SolidWorks