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1

Modified virtual blade method for propeller modelling

Stajuda M., Obidowski D., Karczewski M., Jóźwik K.

Mechanics and Mechanical Engineering

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2018

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Vol. 22, nr 2

603--617

EN

The emergence of large, propeller-based aircraft has revived interest in propeller design and optimization with the use of numerical methods. The flow complexity and computational time necessary to solve complicated flow patterns trailing behind rotating blades, created a need for faster than fully resolved 3D CFD, yet comparably accurate methods for validating multiple design points in shorter time. Improved Virtual Blade Method (VBM) for 2-bladed propeller, including method implementation, analysis and validation against 3D numerical and experimental data is presented. The study introduces adjustments to the original method, accounting for differences between VBM and fully resolved numerical models. These modifications prove to increase the model accuracy for the propeller under consideration and could potentially be applied for different blade configurations as well. The modified Virtual Blade Method allows one to compute the propeller performance with comparable accuracy to 3D CFD computation using only 10% of time needed for one computational point.

2

Symulacja numeryczna przepływu chłodziwa w procesie szlifowania

Stajuda M., Sobczak K., Wójcik R.

Mechanik

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2016

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R. 89, nr 10

1318--1319

PL

Celem badań jest opracowanie zaawansowanego modelu numerycznego przepływu płynu chłodząco-smarującego w procesie szlifowania. W zrealizowanej części projektu przeprowadzono symulacje przepływu powietrza jako medium chłodzącego. W artykule przedstawiono wpływ różnych ustawień kątowych i prędkości wypływu z dyszy na przepływ płynu przez strefę szlifowania.

EN

The objective of the project is to develop an advanced numerical model of a coolant flow in grinding. The accomplished part presented in this article allowed to simulate the flow of air as a cooling medium. The article presents an influence of different angular positions of the nozzle and outflow velocities on the useful flow rate.

3

Investigation on Aerodynamics of Super–Effective Car for Drag Reduction

Cieśliński A., Prym W., Stajuda M., Witkowski D.

Mechanics and Mechanical Engineering

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2016

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Vol. 20, nr 3

295--308

EN

This paper focuses on shape optimization of a car body to be used in Shell Eco Marathon race. The work consists of the review of aerodynamic performance for currently used shapes, definition of the design constraints for the vehicle and recommendations for the final shape to be used in the oncoming Shell Eco Marathon editions. The designs are inspired by winning models, but adjusted to Iron Warriors technology and scaled accordingly to the driver’s space requirements. A range of velocities from 20 km/h to 45 km/h with 5 km/h interval is tested, giving idea about the full model performance. Results are then compared and the best solutions, concerning the coefficient and parameter taking into account the frontal area influence are recommended.

4

Development of a CFD model for propeller simulation

Stajuda M., Karczewski M., Obidowski D., Jóźwik K.

Mechanics and Mechanical Engineering

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2016

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Vol. 20, nr 4

579--593

EN

The article presents a development of numerical model for a single propeller simulation and comparison of obtained results with experimental data available from a test campaign in scale 1:1. Described simulation is a steady state computation taking advantage of Multiple Reference Frame model implemented in Ansys CFX. The paper includes an analysis of rotating domain thickness influence on numerical values of thrust and power. The results indicate that this type of simulation may be sensitive to the sizing of rotating domain especially when disc solidity is low, or when the number of blades is 2, a frequent situation in all electric flight vehicles. The analysis shows that performing simulations, using one domain sizing, for a number of flight scenarios requiring analysis of a few rotational speeds can produce unintuitive results. Therefore, it is suggested to calibrate the model, preferably by experimental results.