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1

Data protection in transactional and statistical applications of databases

Szafrański Boleslaw, Bałazy Rafał

Computer Science and Mathematical Modelling

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2019

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No. 10

31--39

EN

The article describes a discussion on the issue of data protection in databases. The discussion attempts to answer the question about the possibility of using a transactional database system as a system capable of data protection in a statistical database. The discussion is preceded by a reminder of the basic issues related to data protection in databases, including reminder of flow control models, access control models and the inference. The key element of the article is the analysis, based on the example of the Oracle database management system, whether data protection mechanisms in transactional databases can be effective in case of data protection in statistical databases.

PL

Artykuł prezentuje dyskusję dotyczącą problematyki ochrony danych w bazach danych zawierającą próbę odpowiedzi na pytanie o możliwości użycia transakcyjnego systemu bazodanowego jako systemu zdolnego do ochrony danych w statystycznej bazie danych. Dyskusja poprzedzona jest przypomnieniem podstawowych zagadnień związanych z ochroną danych w bazach danych, w tym modeli sterowania przepływem, sterowania dostępem oraz wnioskowaniem. Kluczowy element artykułu stanowi analiza, na przykładzie systemu zarządzania bazą danych Oracle, czy mechanizmy ochrony danych w transakcyjnych bazach danych mogą być skuteczne w przypadku ochrony danych w statystycznych bazach danych.

2

Laboratory tests of stand-alone hydraulic piezo-valve

Skorupka Z.

Journal of KONES

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2018

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Vol. 25, No. 4

385--381

EN

Flow control inside the aviation landing gear shock absorbers is nowadays performed by fixed orifices or by the half-active spring based valves located inside of the device. All of the mentioned solutions are optimized on limited, mostly to one, landing scenarios due to their non-adjustable nature (even spring based valves are treated as passive due to their lack of actual real-time controllability). The easiest way of full hydraulic fluid flow control is to mount in its way a valve, which is able to seamlessly open and close causing the flow to change in wide range. Unfortunately, most of the used solutions are too large or not fast enough to fit the shock absorber requirements. The most promising way is to design tailor-made valve based on a piezo crystal actuator, which is most suitable due to its size and speed. Such a design has been made and tested by the engineers of the Institute of Aviation in Warsaw in Landing Gear Laboratory. In this article, the author describes test campaign of the hydraulic piezo-valve. Several tests have been made in order to assess the design correctness and to determine the basic parameters of the valve. Achieved results, presented in this article, show the full functionality of the solution in laboratory tests according to the design assumptions [8].

3

Experimental observations of flow structures during DEP controlled boiling in a microchannel

Lackowski M., Kwidziński R., Karwacki J., Przybyliński T.

Archives of Thermodynamics

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2018

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Vol. 39, no 1

129--145

EN

The paper presents results of experimental investigation of microchannel boiling flow which was controlled by dielectrophoretic (DEP) restrictor. The DEP restrictor was connected to the microchannel liquid supply tube. Operation of DEP restrictor influenced the flow rate at the microchannel inlet. Resulting changes in flow structures and vapour content along the microchannel were observed and analysed with a high-speed video camera. Video recordings were synchronised with measurements of differential pressure between the channel inlet and outlet. It was found that it is possible to change average void fraction in the microchannel by switching on and off the voltage applied to the restrictor electrodes. However, to achieve significant variation of the void fraction, applied voltage should be of the order of 2000 Vpp. The voltage switching also generates oscillations of the differential pressure. The amplitude of these oscillations is proportional to the voltage magnitude, reaching 35 Pa for 2400 Vpp.

4

Linear genetic programming control for strongly nonlinear dynamics with frequency crosstalk

Li R., Noack B., Cordier L., Borée J., Kaiser E., Harambat F.

Archives of Mechanics

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2018

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Vol. 70, nr 6

505--534

EN

We advance Genetic Programming Control (GPC) for turbulence flow control application building on the pioneering work of [1]. GPC is a recently proposed model-free control framework which explores and exploits strongly nonlinear dynamics in an unsupervised manner. The assumed plant has multiple actuators and sensors and its performance is measured by a cost function. The control problem is to find a control logic which optimizes the given cost function. The corresponding regression problem for the control law is solved by employing linear genetic programming as an easy and simple regression solver in a high-dimensional control search space. This search space comprises open-loop actuation, sensor-based feedback and combinations thereof — thus generalizing former GPC studies [2, 3]. This new methodology is denoted as linear genetic programming control (LGPC). The focus of this study is the frequency crosstalk between unforced, unstable oscillation and the actuation at different frequencies. LGPC is first applied to the stabilization of a forced nonlinearly coupled three-oscillator model comprising open- and closed-loop frequency crosstalk mechanisms. LGPC performance is then demonstrated in a turbulence control experiment, achieving 22% drag reduction for a simplified car model. In both cases, LGPC identifies the best nonlinear control achieving the optimal performance by exploiting frequency crosstalk. Our control strategy is suited to complex control problems with multiple actuators and sensors featuring nonlinear actuation dynamics. Significant further performance enhancement is envisioned in the more general field of machine learning control [4].

5

Sterowanie przepływem jako narzędzie dla zwiększenia efektywności sorbera przepływowego

Sobczak K., Obidowski D., Kocemba I., Maćkiewicz E., Jóźwik K., Pietrasik R., Szynkowska M. I.

Przemysł Chemiczny

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2017

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T. 96, nr 7

1600--1604

PL

Zaprezentowano użyteczność metod numerycznej mechaniki płynów dla zwiększenia skuteczności sorpcji sorbera przepływowego. Przedstawione zjawisko zachodzi w układach przepływowych, dla których prędkości płynącego czynnika nie zapewniają odpowiedniego stopnia jego mieszania, a tym samym czynnik sorbowany ma utrudniony dostęp do powierzchni sorbującej. Prędkość przepływu jest zbyt mała, aby zachodził przepływ burzliwy, a zbyt duża, aby mogło zachodzić efektywne zjawisko dyfuzji.

EN

The efficiency of Hg vapor sorption from the gas stream flowing through an absorber (flow rate 0.5–167 cm³/s) was detd. exptl. on an sulfonitrided steel sheet. The increase of gas velocity resulted in a decrease in sorption efficiency. Computer simulations of the sorption process were performed. The factors causing growth of gas flow turbulence (the distances between the absorber elements and their position relative to the flowing gas) had a significant influence on the process.

6

Modelowanie komputerowe przepływów i jego wykorzystanie do poprawy pracy przykładowego wodociągu

Orłowska-Szostak M.

Proceedings of ECOpole

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2017

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Vol. 11, No. 2

561--569

PL

Zaprezentowano proces powstawania i niestandardowego wykorzystania modelu komputerowego przepływów w grupowym systemie transportu i dystrybucji wody wodociągowej (STDW) zaopatrującym cztery miejscowości gminy Wejherowo. Dane opisujące stan aktualny sieci obejmują m.in. topologię sieci, średnice, materiał oraz wiek przewodów, obiekty współpracujące z układem wodociągowym, występujące rozbiory wody i obecny charakter zapotrzebowania miasta na wodę wodociągową, a także parametry charakteryzujące jakość wody dostarczanej odbiorcom. W procesie gromadzenia tych danych, pozyskiwanych od przedsiębiorstwa wodociągowego, występowały ograniczenia odnośnie do ich asortymentu i dokładności. W tych warunkach starano się maksymalnie wykorzystać posiadane informacje z punktu widzenia niezbędnej wiarygodności powstającego modelu. Podobne podejście zaprezentowano podczas przeprowadzania kalibracji modelu, mając na uwadze, że obie czynności (gromadzenie danych i kalibracja) stanowią czynności komplementarne. Dane pomiarowe dotyczyły produkcji wody na ujęciach oraz ciśnień w wybranych węzłach sieci. W procesie kalibracji modelu wykorzystano zalety symulacji czasowo-przestrzennej, co pozwoliło na optymalne wykorzystanie posiadanych danych pomiarowych. W rezultacie osiągnięty został wysoki stopień korelacji wyników pomiarów w układzie wodociągowym z wartościami zasymulowanymi. Skalibrowany model posłużył do przeprowadzenia kompleksowej analizy pracy systemu. Analiza ta obejmowała m.in. czas przebywania wody w sieci wodociągowej, w poszczególnych jej częściach (tzw. wiek wody), mający istotny bezpośredni wpływ na jakość wody dostarczanej odbiorcom. Zaproponowano również pewne koncepcje modernizacji zmierzające do usprawnienia pracy nieoptymalnie działającego układu wodociągowego miasta. Wspomniane usprawnienie systemu obejmowało przede wszystkim korektę podziału systemu na strefy ciśnienia i sterowanie przepływami w sieci.

EN

In the paper a process of coming into existence and a nonstandard use of the computer model of water transport and distribution system (STDW) for middle size (of about 50,000 inhabitants) city located in Pomorskie region was presented. Collecting the data describing current state of the system the authors concentrated their attention on the network of pipes (the network topology, diameters, material and the age of pipes), objects cooperating with the waterworks system, network fittings, appearing consumptions of water and current character of the water demand in the city and also some parameters being characteristic of a quality of water delivered to the consumers. All these data constituting the base for creating the model STDW were collected in the essential scope and with the essential accuracy. There appeared here some restrictions in the form of the assortment and accuracies of the data which the water authority had at their disposal. In these conditions the authors were trying to exploit to the maximum the gathered data from a point of view of the essential credibility of the model coming into existence. The similar approach was presented while making the calibration of the model bearing in mind that both activities (the completing of the data and the calibration) constitute activities of complementary character. The measuring data concerned water production at the water intakes and pressures occurring in chosen nodes of the water supply network. In the process of the calibration of the model advantages of the extended period simulation were exploited what allowed for the optimal use of the measuring data being for the author disposal. As a result a satisfactory correlation of results of measurements and simulated values has been achieved. The calibrated model was used for conducting the comprehensive work analysis of the system. This analysis included the residence time of water in the water supply network (so-called "age of water") having essential direct impact on the quality of water delivered to consumers. Also some concepts of modernization of the system were offered. They are aiming at streamlining the work of the non-optimal waterworks in the city. The mentioned streamlining the system included correction of the division of the system into zones of pressure and the control of flows.

7

Experimental study on suppression of vortex street behind perforated square cylinder

Teimourian A., Hacışevki H., Bahrami A.

Journal of Theoretical and Applied Mechanics

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2017

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Vol. 55 nr 4

1397--1408

EN

In this study, the effects of entrainment of a fluid through a perforated surface on suppression of the vortex street behind a perforated square cylinder have been studied experimentally. The wake region has been investigated in terms of coherent flow structure, time averaged properties and effectiveness of different perforations. The quantitative measurements revealed that the perforated surfaces are only effective within a width interval of y/D = ±1.0. It has been observed that in the near wake region up to approximately 1.5D downstream the wake, the shedding phenomenon has been suppressed significantly. It has been also demonstrated that velocity profiles and flow structure have been affected by different perforated surfaces and, as a result, coherent structures have been diminished considerably.

8

Optimal Spectrum Utilization and Flow Controlling In Heterogeneous Network with Reconfigurable Devices

Hashmi S. S., Sattar S. A., Soundararajan K.

International Journal of Electronics and Telecommunications

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2017

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Vol. 63, No. 3

269--277

EN

Fairness provisioning in heterogeneous networks is a prime issue for high-rate data flow, wherein the inter-connectivity property among different communication devices provides higher throughput. In Hetnet, optimal resource utilization is required for efficient resource usage. Proper resource allocation in such a network led to higher data flow performance for real-time applications. In view of optimal resource allocation, a resource utilization approach for a reconfigurable cognitive device with spectrum sensing capability is proposed in this paper. The allocation of the data flow rate at device level is proposed for optimization of network fairness in a heterogeneous network. A dynamic approach of rate-inference optimization is proposed to provide fairness in dynamic data traffic conditions. The simulation results validate the improvement in offered quality in comparison to multi-attribute optimization.

9

Monitoring i regulacja ciśnienia w sieci wodociągowej gwarantem obniżenia awaryjności i strat wody

Piechurski F. G.

Gaz, Woda i Technika Sanitarna

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2017

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Nr 4

167--170

PL

Mieszkańcy miasta A zaopatrywani są w wodę, która w całości zakupywana jest od dostawcy hurtowego. W punktach zakupu dokonywany jest pomiar przepływu i ciśnienia wody, która następnie jest dostarczana odbiorcom za pomocą sieci wodociągowej należącej do PWiK. Obecnie sieć wodociągowa budowana jest przede wszystkim z rur i kształtek PEHD. Materiał ten lepiej znosi skutki eksploatacji górniczej niż stal, z której wykonano ok. 30% długości sieci. Dodatkowo inwestycje w sprzęt do systemu monitoringu przepływu i ciśnienia w sieci, wprowadzenie regulacji ciśnienia oraz użytkowanie sprzętu do lokalizacji awarii pozwoliły łącznie na obniżenie strat wody do poziomu 10%.

EN

The citizens in the city A are supplied with water which is being bought in total from one general supplier. Supply points measure amount of purchased water, then water is distributed through water distribution network that belongs to PWiK (water and waste water company). Nowadays water distribution network is built of PEHD pipes and fittings. PEHD has better resistance than steel to deal with mining area challenges. At this moment only 30% of pipelines are made of steel. Additional investment in water monitoring system (flow and pressure monitoring), pressure regulation and modem failure detection system allowed to reduce water loses to 10%.

10

Source term model for streamwise Rod Vortex Generator modelling

Kwiatkowski T., Flaszyński P.

Journal of KONES

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2016

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Vol. 23, No. 4

261--268

EN

In the article, the new method of modelling of Rod Vortex Generators (RVGs) was proposed. RVGs are inclined rods, mounted in boundary layer used to flow control. RVGs were intensively investigated in Institute of Fluid-Flow Machinery in Gdansk, Poland. The research results indicate high potential of RVGs to flow control in wide range of Mach numbers (Mach 0.3-1.45) in the main flow. Due to the flow structure details generated by RVG, it is required to create fine grids in the vicinity of RVGs, which increase the computational cost. In order to overcome this difficulty and reduce computational cost the new numerical models of RVGs are proposed, which use the modification of BAY model. Using BAY model it is not needed to resolve the shape of RVG in detail and it is possible to use orthogonal meshes. The BAY model was originally proposed to predict flows behind thin-plate vortex generators. This model works by adding momentum source term to Reynolds-Averaged Navier-Stokes equations in ANSYS Fluent. The BAY model spatial vectors orientation was modified and some simplifications were performed. The model was calibrated and simulations were carried out for the single rod. The results and effectiveness of modified BAY model were compared with wind-tunnel experiment results and grid-resolved model.

11

Dynamic control for gas pipeline systems

Osiadacz A., Chaczykowski M.

Archives of Mining Sciences

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2016

|

Vol. 61, no. 1

69--82

EN

An algorithm for optimal control of a gas network with any configuration based upon hierarchical control and decomposition of the network is described. Local problems are solved using a gradient technique. The subsystems are coordinated using „good coordination” method to find the overall optimum. Discrete state equation for the case in which output pressures are treated as elements of the control vector has been formulated. Results of investigations are included.

PL

W artykule omówiono algorytm optymalnego sterowania siecią gazową o dowolnej konfiguracji wykorzystujący teorię systemów hierarchicznych oraz zasady dekompozycji systemu na podsystemy. Lokalne problemy optymalizacji są rozwiązywane stosując metodę gradientową. Koordynacja rozwiązań lokalnych pozwala na znalezienie rozwiązania optymalnego dla całego systemu. Optymalizowany system opisano za pomocą dyskretnego równania stanu przyjmując, że elementami wektora sterowania są wartości ciśnienia wyjściowego elementów nierurowych. W artykule przedstawiono rezultaty badań algorytmu.

12

Shock wave induced flow separation control by Air-Jet and Rod Vortex Generators

Tejero F., Doerffer P., Szulc O.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2015

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Vol. 19, No 2

167--180

EN

Flow separation control by Vortex Generators (VGs) has been analyzed over the last decades. The majority of the research concerning this technology has been focused on subsonic flows where its effectiveness for separation reduction has been proven. Less complex configurations should be analyzed as a first step to apply VGs in transonic conditions, commonly present in many aviation applications. Therefore, the numerical investigation was carried out for a Shock Wave-Boundary-Layer Interaction (SWBLI) phenomenon inducing strong flow separation at the suction side of the NACA 0012 profile. For this purpose, two kinds of VGs were analyzed: well documented Air-Jet Vortex Generators (AJVGs) and our own invention of Rod Vortex Generators (RVGs). The results of the numerical simulations based on the RANS approach reveal a large potential of this passive flow control system in delaying stall and limiting separation induced by a strong, normal shock wave terminating a local supersonic area.

13

Numerical simulations of gap flow above rotating disk

Wasilczuk F., Flaszyński P., Doerffer P.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2015

|

Vol. 19, No 2

89--100

EN

A rotating disk can be considered a basic configuration for the investigations of the impact of various conditions on the flow through the clearance between the shrouded turbine blade and the casing. Numerical calculations using Fine/Turbo Numeca were conducted to examine the influence of the rotational velocity and the pressure difference across the disk on the flow conditions, especially the mass flow through the clearance. The results were validated using the experimental data. Moreover, the flow field was investigated to reveal the vortices induced in the flow. The calculations showed a significant drop of the mass flow with a rise of the rotation velocity. Additionally, the vortex created upstream of the disk at higher rotation velocities was observed. The phenomenon of separation at the edge of the disk was investigated.

14

Podstawy budowy, regulacji rozpływu i monitoringu sieci odmetanowania

Dziurzyński W., Krach A., Pałka T., Krawczyk J., Wasilewski St.

Przegląd Górniczy

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2015

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T. 71, nr 7

34--42

PL

W artykule przedstawiono podstawy funkcjonowania monitoringu sieci odmetanowania. Ocenia się, że wprowadzenie do praktyki monitoringu i regulacji pozwoli na poprawę efektywności ujęcia metanu. Omówiono podstawy teoretyczne regulacji przepływu mieszaniny metanu i powietrza w rurociągu odmetanowania oraz przedstawiono koncepcję automatycznej regulacji przepływu w sieci rurociągu odmetanowania. Przyjęto, że zastosowanie metod numerycznych i programu komputerowego VentOdmet do wyznaczania stanu sieci odmetanowania w połączeniu z obliczeniami programem VentGraph modelującym rozpływ powietrza w sieci wentylacyjnej rejonu umożliwia badanie wzajemnego wpływu tych dwóch sieci, w tym obliczanie rozpływu gazu w rurociągu odmetanowania i regulacji rozpływu. Przedstawiono przykład obliczeń na opracowanym modelu numerycznym wykonanej regulacji rozpływu metanu w sieci rurociągu odmetanowania kopalni „Z”. Wyniki obliczeń przedstawiono w postaci graficznej, korzystając ze schematu połączeń rurociągu odmetanowania.

EN

This paper briefly outlines the operating principles of monitoring of the methane drainage network. The introduction of methane flow control and monitoring to the mining practice is expected to help improve the efficiency of methane recovery. Theoretical background of the regulation of the flow in the methane drainage network and a concept of automatic flow control of the drainage system are presented. It is assumed that the application of specific numerical procedures and co-operation of the computer program VentOdmet, which is modelling operation of the methane drainage network, with the VentGraph program for modelling the airflow in ventilation network in the area, should allow for the interactions between those two networks to be reliably tested, including calculation and control of the methane drainage flows. Regulation of the drainage system at the colliery Zofiówka is presented as an example. Calculation data have been displayed graphically by use of the schematic diagram of methane control pipeline connections.

15

Eksperymentalne badania wpływu spoilera na aerodynamiczne obciążenie skrzydła samolotu

Krzysiak A.

Modelowanie Inżynierskie

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2015

|

T. 25, nr 56

71--76

PL

W obecnie użytkowanych samolotach do sterowania obciążeniem skrzydła, w fazie lądowania lub w trakcie gwałtownego podmuchu powietrza, stosowane są spoilery. W niniejszej pracy przedstawiono wyniki eksperymentalnych badań, wpływu wychylenia spoilera na zmianę rozkładu aerodynamicznego obciążenia skrzydła. Do badań wykorzystano model półskrzydła samolotu. Obciążenie aerodynamiczne modelu mierzone było przez dwie wagi aerodynamiczne, umieszczone u jego podstawy, oraz osiem mostków tensometrycznych, naklejonych wzdłuż rozpiętości półskrzydła. Ponadto, w dwóch wybranych przekrojach, dokonywano pomiaru rozkładu ciśnienia na powierzchni zewnętrznej modelu wzdłuż cięciw skrzydła. Badania zrealizowano w ramach projektu europejskiego STARLET.

EN

In contemporary aircrafts to wing load control, during its landing phase or sudden gusts the spoilers are used. This paper presents, the results of experimental studies of the effect of spoiler deflection, on the wing load distribution along its span. The study was carried out on the semi-half aircraft wing model. The aerodynamics loads were measured by two aerodynamic balances placed at the model base, and by eight strain gauge bridges, distributed along its span. Moreover, in the two selected wing cross sections, the pressure distributions on the outer wing surface, along the wing chords, were measured. Presented research work was carried out within the framework of the European project STARLET.

16

Model of Pressure Distribution in Vortex Flow Controls

Mielczarek S., Sawicki J. M.

Archives of Hydro-Engineering and Environmental Mechanics

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2015

|

Vol. 62, nr 1-2

41--52

EN

Vortex valves belong to the category of hydrodynamic flow controls. They are important and theoretically interesting devices, so complex from hydraulic point of view, that probably for this reason none rational concept of their operation has been proposed so far. In consequence, functioning of vortex valves is described by CFD-methods (computer-aided simulation of technical objects) or by means of simple empirical relations (using discharge coefficient or hydraulic loss coefficient). Such rational model of the considered device is proposed in the paper. It has a simple algebraic form, but is well grounded physically. The basic quantitative relationship, which describes the valve operation, i.e. dependence between the flow discharge and the circumferential pressure head, caused by the rotation, has been verified empirically. Conformity between calculated and measured parameters of the device allows for acceptation of the proposed concept.

17

Stanowisko do badań proporcjonalnych regulatorów przepływu

Lisowski E., Krawczyk M.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

|

2014

|

z. 103

127--128

EN

This paper presents a research position into study proportional flow controls with the results of research. The study used two-way proportional flow control UDRDE6 of Ponar-Wad¬owice

PL

W pracy przedstawiono budowę stanowiska do badań dwudrogowego proporcjonalnego regulatora przepływu, który znajduje zastosowanie wszędzie tam, gdzie zależy nam na stabilnym i precyzyjnym zasilaniu odbiorników. Jak wykazały wstępne badania, charakterystyka pracy zaworu jest daleka od zakładanej.

18

Novel method of physical modes generation for reduced order flow control-oriented models

Morzyński M., Nowak M., Stankiewicz W.

Vibrations in Physical Systems

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2014

|

Vol. 26

189--194

EN

Physical flow modes are of particular interest for Reduced Order Flow Control-Oriented Models. Computation of physical modes as the eigensolution of linearized Navier-Stokes equations is a cumbersome and difficult task, especially for large, 3D problems. Instead we propose the solution of Navier-Stokes equation in the frequency domain and investigation of the system response to local or global perturbation. The flow variables are perturbed around steady basic state and the system response is used to construct mode basis suitable for ROMs.

19

Metoda TPM jako element poprawy ciągłości przepływu

Michlowicz E., Smolińska K.

Logistyka

|

2014

|

nr 3

4330--4337

PL

Potrzebną do prawidłowego funkcjonowania systemów produkcyjnych ciągłość przepływu materiałów można uzyskać różnymi sposobami i metodami sterowania. Od strony infrastruktury technicznej ważnym zadaniem jest zapewnienie dużej bezawaryjności maszyn, urządzeń i całych linii produkcyjnych. Cele te można zrealizować poprzez stosowanie Total Productive Maintenace TPM. W opracowaniu przedstawiono analizę TPM dla procesów wytrawiania i walcowania w Walcowni Zimnej Blach jednej z hut stali.

EN

The continuity of the flow of materials needed for correct operation of manufacturing systems can be achieved using different means and control methods. As far as the technical infrastructure is concerned, ensuring high reliability of machines, devices and whole manufacturing lines is an important task. These objectives can be achieved through the use of Total Productive Maintenance (TPM). Article present TPM analysis for pickling and rolling processes in tins Cold Rolling Mill in one of steelworks.

20

The effects of trailing edge blowing on aerodynamic characteristics of the NACA 0012 airfoil and optimization of the blowing slot geometry

Yousefi K., Saleh R.

Journal of Theoretical and Applied Mechanics

|

2014

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Vol. 52 nr 1

165--179

EN

The effects of blowing and its parameters including the jet amplitude, blowing coefficient and jet width in order to flow control was evaluated for a NACA 0012 airfoil. The flow was considered as fully turbulent with the Reynolds number of 5 · 105, and the Menter shear stress turbulent model was employed. Tangential and perpendicular blowing at the trailing edge were applied on the airfoil upper surface, and the jet widths were varied from 1.5 to 4 percent of the chord length, and the jet amplitude was also selected 0.1, 0.3 and 0.5. In the tangential blowing, the results showed that when the blowing amplitude increases, the lift- to-drag ratio rises by 15 percent, however, the smaller amounts of the blowing amplitude are more effective in the perpendicular blowing. Furthermore, when the blowing jet width rises, the lift-to-drag ratio increases continuously in the tangential blowing and decreases quasi- linear in the perpendicular blowing. In this study, the blowing jet width 3.5 and 4 percent of the chord length for the tangential blowing was selected as optimal values as well as smaller amounts of blowing jet width are more suitable for the perpendicular blowing. Finally, the lift-to-drag ratio was increased by 17 percent for the tangential blowing in the angle of attack of 18 degrees.