In this paper, a fuzzy clustering system is presented to display the flow field changes in the rotor outlet of centrifugal Turbomachinery. What is important in the research done in the field of Turbomachinery is the need for all the fields to properly understand the phenomena of flow inside the turbomachines, which has complexities. For this reason, the most advanced laboratory equipment is used in this regard, which is associated with issues such as time consuming, high costs, and a large number of required tests, and doubles the importance of simulating and observing current phenomena through artificial intelligence algorithms. The present system operates on the basis of fuzzy clustering so that the spatial data (from the PIV measurement system) by the number of specific clusters to the field display in the initial time; then, by applying changes to the cluster related to the time series (from the system measurement of LDA) that contains the recorded changes of the current during the time of the data mining, the new field data are obtained at a new time step and the clustering of the data shows the variation of the flow field in the fuzzy environment. In this paper, the flow field was investigated for 6 successive steps, and the results of the system output showed the variation of the flow field from the rotor rotation at different angles.

One of the goals of computational fluid dynamics for Turbomachinery is the prediction of their performance such as the ratio of pressure, efficiency, and the nature of the flow. In this research, which consists of two parts, in the first part were performed steady and unsteady simulation methods on stage of the axial flow Turbomachinery and results validated. In this regard, two numerical steady methods including a frozen rotor and stage, and three transitional numerical methods including standard transitions, time transformation, and profile transformation were used. Transient methods provided a more accurate prediction. In transient methods, it was observed that transient effects including wake, stator leading edge bubble and flow separation can be obtained more clearly, which were found to be weaker in other methods. In order to solve the numerical flow field used of structured grid and SST turbulence model was used for modeling turbulence. In the second part of the paper, 9 changes were investigated to the geometric changes, such as roughness in the blade surfaces, clockwise and counter-clockwise rotation of the foil sections, the creation of radius in the roots of the blades, and create of the axial distance between the blades.

Micro scale gas turbines are low cost, simplified versions of full scale jet engines. A unique feature of their design are centrifugal compressor impellers that are selected from automotive low cost, high quality turbocharger components. The present article is dedicated to the practical design of a micro scale centrifugal compressor diffuser that suits a reduced scale, turbojet engine. The idea of using a simplified method comes from the requirement from fast geometry generation for a prototype design. The chosen approach is suitable when the time is crucial and available resources are limited. The chosen simplified analytical model is based on Turbomachinery physics. The obtained results are verified by detailed data from successful designs such as KJ66, MW54 and TK50. For a prototype design, GT60 results where compared with a numeric simulation in the ANSYS CFX environment. The difference in isentropic efficiency, numerical prediction in comparison to compressor flow map was less than 3%. This is acceptable for preliminary calculations due to the difference in compressor stator design.

Variable fill fluid couplings are used in the speed control units. Also, variation in coupling oil volume is used in adapting one size of coupling to a wider range of power transmission applications. Available model for the partially filled fluid couplings, has a good performance for couplings with fixed amount of oil but their performance will be degraded if they are used for the variable fill couplings. In this paper, the current model for partially filled fluid couplings is modified to have better performance for variable fill couplings. For this purpose, the circulation loss calculation is modified and also, the effect of oil temperature variations and blade thickness are included in the model. The effect of these modification on the model performance are investigated in couple of simulations. Comparing the simulation results with the available experimental data shows that the suggested modifications can improve the model performance very well.

Most Axial compressors performance in aerodynamic applications systems are limited, due to flow instability at low mass flow rate One of these Instabilities is surge phenomena. In the present study, analysis of three-dimensional unsteady Navier-Stokes equations in multistage Turbomachinery is studied by Fluent software and (k-ε ) turbulence model and SKE The results showed that this model compared with conventional types, to Turbomachinery is more accurate and has faster convergence rate. And at investigate the compression system behavior when occurring phenomenon surge and changes of pressure and mass flow rate fluctuations over time, in different parts of the compressor performance is acceptable accuracy. So that the average mass flow rate calculated for the NASA Rotor 67 in the present study and the model SKE equal to 34/23 (kg /s) and laboratory data have shown the value of 34/61 (kg /s). It also became clear that under surge condition, by increasing the design round, vibration will have much decrease.

Improvement of turbine blades is currently the prime area of research dedicated to the development of more efficient gas turbines. This study examines the structural performance of the gas turbine rotor and stator blades with the implementation of Kagome truss-core structure as inner topology. The truss-core structure was hypothesised to improve the stress behaviour of the blade by reducing the mass and, hence, the centrifugal force induced by rotation, while remaining robust enough to withstand bending stress induced by the flow. In order to analyse the stress state of the truss-core model, fluid flow analysis of transonic Turbomachinery was performed via the Frozen Rotor technique in ANSYS CFX and then coupled with ANSYS Mechanical. As a result, the combined surface load of the rotor was obtained and used to estimate the structural performance. By examining the obtained complex stress state of the rotor blades, the truss-core density-dependent structural performance was derived for the given initial and boundary conditions.

Turbodrill (turbine down hole motor) has been recently proposed by the authors as the preferred drive mechanism with high rotation speed for hard rocks drilling for deep mineral exploration applications. Turbodrill is a type of hydraulic axial Turbomachinery in which turbine motor section has multistage of rotors and stators that convert the hydraulic power provided by the drilling fluid to mechanical power with diverting the fluid flow through the stator vanes to rotor vanes. This paper presents a methodology for designing multistage turbodrills with asymmetric rotor and stator blades configurations. The numerical simulation approach and the simulations results carried out using computational fluid dynamics (CFD) code for the proposed small size model of turbodrill stage with different drilling fluid (mud) types and various mass flow rates are presented. As a result optimum operational parameters are proposed for gaining the required rotation speed and torque for hard rocks drilling.

The flow behavior inside the shrouded disk system is of importance in appropriate design of Turbomachinery cavities and turbine test cell hydraulics dynamometer. The turbulent incompressible flow is analyzed for the shrouded disk system with axial clearance. The flow core behaves as a Batchelor type structure when a weak inflow is imposed on the disk cavity. By increasing the inflow, the central core disappears and the tangential velocity distribution is changed to Stewartson type structure. The central core again reappears by increasing the Reynolds number. The moment coefficient of rotary disk depends on superimposed flow rate coefficient and dimensionless geometrical parameters. Moment coefficient increases with increasing inflow rate while the other parameters remain constant. The coefficient is reduced by increasing the Reynolds number. Moreover, it increases with both increasing rotary and stationary disks axial distance, and decreasing clearance ratio. The experimental results of a cavity with radial clearance are used to validate the accuracy of the simulation. The results of this analysis and its development can be used in the design of turbine test cell hydraulics dynamometers.

A correlation-based transition model has been developed by Langtry and Menter for modern computational fluid dynamics codes, which is widely used for transition prediction in the field of Turbomachinery and aircraft. Langtry’s transition model could simulate bypass, laminar separation and streamwsie Tollmien–Schlichting wave transition. Even so, this model has no ability to predict the transition due to crossflow instabilities in three dimensional boundary layer. In this paper, a new correlation-based transport equation for the transition due to crossflow instabilities has been established based on the experiment data and self-similar equations. The new transport equation is introduced to describe the crosswise displacement thickness Reynolds number growth in boundary layer. This new equation is added to Langtry’s intermittency factor equation to improve the ability of predicting transition. Finally, coupling of these transport equations and Shear Stress Transport (SST) turbulence model completes the new improved transition turbulence model.Comparisons of predictions using the new model with wind tunnel experiments of NLF (2) -0415 infinite swept wing and 6: 1 inclined prolate spheroid validate the predictive qualities of the new correlation based transport equation.