Wyniki wyszukiwania - BazTech

1

Comparing methods of calculating aircraft engine emissions of harmful exhaust components during the takeoff and landing cycle in the airspace of an airport

Głowacki Paweł, Kalina Piotr, Kawalec Michał

Transactions on Aerospace Research

|

2022

|

Nr 2 (267)

62--68

EN

An airport authority needs accurate information about the actual amount of harmful emissions being generated within its airspace, to be able to take measures leading to their reduction. This article presents two methods for estimating the amount of these emissions from aircraft engines during the take off and landing cycle (LTO) in the airspace of a medium-sized airport: one based on the total amount of the aircraft annually operated in it, and a second, more precise, one for a specific airline annually operating at this airport. The conclusions stemming from the comparison of these methods can support the introduction of operational and technical procedures reducing harmful emissions in the airport airspace during LTO cycle.

2

Determination of Ranges of Unstable Operation of Axial Compressor for Aircraft Turbine Engines

Kozakiewicz Adam, Adamczyk Maciej, Majcher Maciej

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

|

2022

|

Vol. 13, Nr 1 (47)

45--56

EN

Currently, strict requirements are set for aircraft turbine engine performance, which requires introducing larger, more complex, and more loaded compressors. In sub-assemblies designed in this manner, a vital challenge is to maintain stable compressor operation across wide range of operating conditions. This article presents the results of analysis and estimation of the range of unstable operation of an example axial compressor for a turbofan jet engine with high mass flow ratio. The analyses and numerical simulations performed made it possible to estimate the limit performance for compressor operation for two particularly important phases of flight.

PL

Współcześnie stawia się wysokie wymagania wobec parametrów osiąganych przez lotnicze silniku turbinowe, co powoduje konieczność wprowadzania do konstrukcji coraz większych, bardziej skomplikowanych i obciążonych sprężarek. W tak projektowanych podzespołach istotnym wyzwaniem jest zachowanie stabilności pracy sprężarki w szerokim zakresie warunków operacyjnych. W niniejszym artykule przedstawiono wyniki analizy i oszacowania zakresu niestatecznej pracy przykładowej sprężarki osiowej do dwuprzepływowego silnika turbinowego o dużym stopniu podziału masowego natężenia przepływu. Przeprowadzone analizy i obliczenia pozwoliły na oszacowanie granicznych parametrów pracy sprężarki dla dwóch szczególnie istotnych faz lotu samolotu.

3

Areas of Investigation into Air Intake Systems for the Impact on Compressor Performance Stability in Aircraft Turbine Engines

Kozakiewicz Adam, Adamczyk Maciej, Wróblewski Mirosław

Advances in Science and Technology. Research Journal

|

2022

|

Vol. 16, no 1

62--74

EN

The high demands placed on aircraft turbine engines necessitate the use of the latest engine compressors which must be increasingly efficient and more robust due to the increased loads. The key safety issue in this context is to ensure compressor stability over all engine speed ranges and aircraft flight regimes. This paper presents selected areas of research into surge and stall of axial compressors used in aircraft turbine engines based on scientific publications in recent years. On the basis of the analysed literature the authors defined the main research areas into compressor surge, namely: air intake research, compressor research and combined air intake and compressor system research. On the background of the conducted analysis the authors has presented their own areas of research. The aim of this work is to search for an intake-compressor design more passively resistant to stall or surge phenomena without necessity of implementation of complex control systems to prevent compressor stall.

4

The aircraft engines in the land vehicles

Walentynowicz Jerzy

Combustion Engines

|

2021

|

R. 60, nr 4

52--59

EN

The examples of the applications of the aircraft engines to propulsion of the heavy armored land vehicles are presented in this paper. They provide the power necessary for high mobility of these land vehicles, which have a weight much greater than trucks. These engines were mass produced and thus were readily available. It was easier to repair damaged engines, too. Both spark-ignition and compression-ignition piston engines as well as turbocharged engines were used to propulsion of the armored vehicles. General solutions of the dual-purpose engines for the vehicles during the First and Second World War as well as the engines used nowadays are presented. Attention is also given to the specific solutions of these engine assemblies. Their basic technical and operational parameters are described. The implications of adapting aircraft engines to land vehicles were analyzed.

5

Simulations of hot-gas flow in internally cooled cascade of turbine vanes

Sznajder Janusz

Journal of KONES

|

2019

|

Vol. 26, No. 2

151--158

EN

An experiment in cooling of gas turbine nozzle guide vanes was modelled numerically with a conjugate viscousflow and solid-material heat conduction solver. The nozzle vanes were arranged in a cascade and operated in highpressure, hot-temperature conditions, typical for first turbine stage in a flow of controlled-intensity, artificiallygenerated turbulence. The vane cooling was internal, accomplished by 10 channels in each vane with cooling-air flow. Numerical simulations of the experiment were conducted applying two turbulence models of the k-omega family: k-omega-SST and Transition SST implemented in the ANSYS Fluent solver. Boundary conditions for the simulations were set based on conditions of experiment: total pressures and total temperature on inlet to cascade, static pressure on the outlet of the cascade and heat flux on the surface of cooling channels. The values of heat flux on the surface of cooling channels were evaluated based on Nusselt numbers obtained from experiment and varied in time until steadystate conditions were obtained. Two test cases, one with subcritical outlet flow, and another one, with supercritical outlet flow were simulated. The result of experiment – distributions of pressure, surface temperature, and heat transfer coefficients on the vane external surface were compared to results of numerical simulations. Sensitivity of the vane surface temperatures and heat transfer coefficients to turbulence models and to boundary-condition values of parameters of turbulence models: turbulence energy and specific dissipation of turbulence energy was also studied.

6

Modelling of vane and rotor blade rows in simulations of gas turbine performance

Sznajder Janusz

Journal of KONES

|

2019

|

Vol. 26, No. 1

183--190

EN

A method of modelling of nozzle and rotor blade rows of gas turbine dedicated to simulations of gas turbine performance is proposed. The method is applicable especially in early design stage when many of geometric parameters are yet subject to change. The method is based on analytical formulas derived from considerations of flow theory and from cascade experiments. It involves determination of parameters of gas flow on the mean radius of blade rows. The blade row gas exit angle, determined in turbine design point is a basis for determination of details of blade contour behind the throat position. Throat area is then fixed based on required maximum mass flow in critical conditions. Blade leading edge radius is determined based on flow inlet angle to the blade row in the design point. The accuracy of analytical formulas applied for definition of blade contour details for assumed gas exit angle was verified by comparing the results of analytical formulas with CFD simulations for an airfoil cascade. Losses of enthalpy due to non-isentropic gas flow are evaluated using the analytical model of Craig and Cox, based on cascade experiments. Effects of blade cooling flows on losses of total pressure of the gas are determined based on analytical formulas applicable to film cooling with cooling streams blowing from discrete point along blade surface, including leading and trailing edges. The losses of total pressure due to film cooling of blades are incorporated into the Craig and Cox model as additional factor modifying gas flow velocities.

7

The Impact of Damage to the Compressor on the Operating Parameters of the Pratt & Whitney 206B2 Turbine Engine

Przybyła B., Zapałowicz Z.

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

|

2018

|

Vol. 9, Nr 1 (31)

61--78

EN

The article presents the impact of damage to the centrifugal compressor of the P&W 206B2 turbine engine, built in the EC-135p2 helicopters EC-135p2. The damages are caused by sucking the foreign bodies to the inlet, what results in the changes of exploitation parameters of the engine and thermodynamic parameters of operating medium. On the basis of the parameters, measured during engine operation, such as: rotation speed of the rotor of the compressor – n₁, the rotation speed of the turbine shaft of the drive – n₂, the gas temperature at the outlet of the turbine driving of the compressor – T4.2, and the fuel flow rate - mp, distributions of these parameters in various cross- sections of the engine were determined and compared. Then, on their basis, the CFD analysis of air flows in new and damaged compressors was performed.

PL

W artykule przedstawiono wpływ uszkodzeń sprężarki promieniowej turbinowego silnika śmigłowcowego P&W 206B2, zabudowanego na śmigłowcach EC-135p2, spowodowanych zasysaniem ciał obcych do wlotu, na zmianę parametrów eksploatacyjnych silnika oraz termodynamicznych czynnika roboczego. Na podstawie parametrów zmierzonych podczas eksploatacji silnika, takich jak: prędkość obrotowa wirnika turbiny wytwornicowej – n₁, prędkość obrotowa wirnika turbiny napędowej – n₂, temperatura gazów na wylocie z turbiny wytwornicowej – T3.1 oraz masowe natężenie przepływu paliwa – mp, wyznaczono i porównano rozkłady tych parametrów w poszczególnych przekrojach silnika. Następnie na ich podstawie wykonano analizę CFD przepływu powietrza przez nową oraz uszkodzoną sprężarkę.

8

Impact of work of turbine adaptive engines for the natural environment

Ćwik D., Kowalski M., Steżycki P.

Journal of KONES

|

2018

|

Vol. 25, No. 4

509--516

EN

The article describes the problem of the operation of turbine jet, adaptive engine work on the natural environment. In particular, the analysis of noise generated by turbine jet engines has been made. It points out possible directions of noise decrease with particular emphasis upon structural changes within the engines, the task of which is to reduce the noise mission. The example of the modernization is based upon the “bypass” type of one-flow turbine jet engine. The essay contains theoretical basis of calculation of the noise emission level and the results, which graphically indicate a relative level of noise of this type of engine depending upon the amount of discharged air and the diameter of the discharge nozzle and the radius, upon the basis of which the noise level is determined. This work also includes a comparison of the relative noise level of this type of engine with regard to one-flow turbine engine equipped with the function of air discharge to the environment and with regard to two-flow turbine jet engine equipped with air stream flow mixing device. The use of low-emission combustion chambers in the "bypass" turbine engine was indicated. This allowed addressing the problem of emissions of toxic exhaust components by this type of aircraft engines. At the same time, the dependence of this emission related to the mass of fuel used on the engine's thrust range was indicated. The article was concluded with a short summary.

9

Electrochemical machining - special equipment and applications in aircraft industry

Ruszaj A., Gawlik J., Skoczypiec S.

Management and Production Engineering Review

|

2016

|

Vol. 7, No. 2

34--41

EN

Electrochemical machining is an unique method of shaping in which, for optimal parameters tool has no wear, surface layer properties after machining are similar to the core material and surface quality and accuracy increase together with material removal rate increase. Such advantages of electrochemical machining, besides of some ecological problems, create industry interest in the range of manufacturing elements made of materials with special properties (i.e. turbine blades of flow aircrafts engines). In the paper the nowadays possibilities and recent practical application of electrochemical machining in aircraft have been presented.

10

Przegląd metod uszczelniania wirników turbin lotniczych

Przybyła B., Zapałowicz Z.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

|

2015

|

z. 87 [291], nr 3

235--243

PL

W artykule przedstawiono najczęściej stosowane w praktyce sposoby przeciwdziałania przeciekom strumieni powietrza lub spalin pomiędzy wirnikiem a korpusem lotniczej turbiny gazowej, materiały stosowane do budowy uszczelnień oraz wady i zalety poszczególnych rozwiazań konstrukcyjnych. Szczegółowo opisano następujące rozwiązania konstrukcyjne: uszczelnienie przez wykonanie wgłębienia w materiale końcówki łopatki wirnikowej, uszczelnienie labiryntowe, wykorzystanie do uszczelniania materiałów odpornych na ścieranie (np. węglikowe płytki zabezpieczające) oraz materiałów tworzących tzw. „plaster miodu”.

EN

In this paper, the most frequently used in practice, the prevention of leakage of exhaust gas stream between the rotor and the housing aviation gas turbine, the materials used in the construction seals and the pros and cons of each design solutions have been presented. The following design solutions: the seal by making a recess in the material of the rotor blade tip, a labyrinth seal for sealing, the use of wear-resistant materials (e.g. Carbide protective plate) and the materials making up the so-called „Honeycomb” have been described in detail.

11

Numerical simulation of thermally loaded aircraft engine turbine blade covered with thermal barrier coating - TBC

Łazarczyk M., Domański R.

Journal of KONES

|

2012

|

Vol. 19, No. 3

271-277

EN

The objective of this thesis is to present the impact of the turbine blade cooling on blade material temperature as well as to assess advantages and disadvantages of applied cooling method (TBC coating combined with internal cooling). To calculate the conjugated heat transfer analysis generating 3d model and mesh of the blade and its cooling was required. Model mesh was covered with boundary layer in order to properly simulate conditions near the blade walls and obtain accurate results. Calculated blade was put in the canal simulating hot combustion gasses flow. Geometry of model described above was created using Unigraphics NX5 program based on drawings obtained from available literature, and data acquired from the Internet. The discretization was done in commercial pre--processor GAMBITŽ. Conjugated heat transfer analysis was conducted in program FLUENTŽ for two different cases, where the TBC material properties were changed. The goal of this thesis was to obtain temperature fields and distribution in the turbine blade airfoil and to evaluate if applied cooling is sufficient to cool down this thermally loaded part of the engine. Calculated results show that proposed blade heat protection with TBC and internal cooling canal is insufficient during steady state condition, especially on the blade leading and trailing edge. In these two locations, the TBC coating is overheated, and the high temperature level of blade material is unacceptable for materials used in jet engine turbine industry.

12

Reduction emission level of harmful components exhaust gases by means of control of parameters influencing on spraying process of biofuel components for aircraft engines

Jankowski A.

Journal of KONES

|

2011

|

Vol. 18, No. 3

129-134

EN

The aim of the research is to test the fuel additives which decrease dimensions of atomised fuel drops, by applying changes to the specific parameters which impact the atomisation process. Those parameters include density, surface tension, viscosity and the viscosity index. Dimensions of drops of biofuels are much bigger compared to hydrocarbon fuels. By modifying the physical and chemical parameters of biofuels, dimensions of drops in an atomised fuel stream should become smaller. Those dimensions play a major role for the level of emissions of hydrocarbon and carbon monoxide, as well as mainly nitrogen oxides and particulates. The research on emissions of toxic components of fuel is relatively advanced today in the field of piston combustion engines, especially for use in car vehicles. However, the dynamic development of the air transport brings more pressure on the issue of toxic emissions in the case of aircraft engines. The level of toxic emissions from aircraft engines may be from ten up to even several thousand times greater than the level of emissions from piston engines. The issue of how biofuel additives can affect the process of fuel atomisation and thus enable the control over the atomisation to obtain the smallest possible drops leading to reduced nitrogen oxides emissions is a new and original issue. The reduced nitrogen oxides emissions in the case of biofuels is of utmost significance because, according to latest knowledge, those levels are increasing.

13

Geometrical Features Analysis of Guide Apparatus of Aircraft Engine

Kołodziej A., Gapiński B.

Machine Dynamics Research

|

2010

|

Vol. 34, No. 3

106-114

EN

Analysis of record of geometrical features in engineering drawing of axial-symmetrical elements applied in aircraft technique was presented. For guide apparatus of aircraft engines it was shown that measurement and verification of quality of geometry according to criteria of diameter and form deviation (roundness deviation) are not defined and documented. It was pointed out that during conducting measurements one takes subjective criteria for measurement and evaluation of results. On the basis of selected measurements of diameters and roundness deviations the reasons of results discrepancy were presented. This discrepancy was caused by a model of roundness error, improper selection of number of measuring points and application of improper datum feature.

14

Influence of geometry and type of cooling holes on thermal load of combustion chamber

Swiatek M., Domański R.

Journal of KONES

|

2010

|

Vol. 17, No. 4

485-494

EN

The objective of this thesis is to compare various methods of combustor wall cooling and their effectiveness by numerical simulations. It was determined that the first task was to verify how much air is coming through single axial hole with 3.5% pressure drop between hot and cold part of combustion chamber. The results from this flow check serve as a base template for generating more accurate and precise models of single axial hole cooling as well as calculation of hole diameter for multihole cooling. Second task was to generate more sophisticated single hole model with boundary layer in order to better simulate the conditions in areas near the combustion chamber walls and get more accurate results. The same method was used to create multihole model. In order to compare efficiency, all created domains in every model have the same volume, model settings, operating and boundary conditions. Geometry of all models described above is created using SIMENS NX4 and SIMENS NX5 program based on drawings obtained from available literature, and data acquired from the Internet. The discretization into a structural finite volume grid took place in commercial pre-processor GAMBITŽ (GAMBIT and FLUENT - commercial CFD codes from Ansy s Inc). The airflow andheat exchange will be calculated using program FLUENTŽ. The results were shown in the thesis in terms of several comparative pictures of the temperature fields in the combustion chamber domain, and graphs representing difference in temperature fields on cooling wall of the combustion chamber.

15

Combustor liner cooling methods - numerical simulation

Lazarczyk M., Domański R.

Journal of KONES

|

2010

|

Vol. 17, No. 4

277-286

EN

The objective of this thesis is to compare various methods of combustor wall cooling and to evaluate advantages and disadvantages of each applied cooling methods. It was determined that the flrst task was to verify how much air is coming through singe radial hole with 2.5% pressure drop between hot and cold part ofcombustion chamber. Flowcheck was calculated also to see how geometry of cooling hole affects hole effective area. Second task was to generale 3d model and mesh of both calculated types of cooling. Each model mesh was covered with boundary layer in order to better simulate conditions near the combustion chamber walls and obtain accurate results. In order to run back-to-back analysis, all created models have the same number of mesh elements, same materials used, samefluent settings, same operating and boundary conditions. Geometry of all models described above was created using Unigraphics NX4 program based on drawings obtained from available literature, and data acquired from the Internet. The discretization was done in commercial pre-processor GAMBITŽ. The airflow and conjugated heat transfer analysis was calculated in program FLUENTŽ. The goal of this thesis was to obtain temperature fields and distribution in the combustion chamber domain (lip and panel wall) and to evaluate if applied cooling is sufficient to cool down heat loaded part of the combustor chamber.

16

The analysis of chosen methods of rapid prototyping of casting models for blades of aircraft engines

Budzik G., Matysiak H., Pacana J., Cygnar M.

Silniki Spalinowe

|

2009

|

R. 48, SC1

283--288

EN

The article presents the analysis of chosen methods of rapid prototyping (RP) having application in process of manufacturing of casting models of blades of aircraft engines. The additive methods and also the diminished methods have been analysed. The numeric controlled milling machine (CNC) MDX-40 production of Roland Company has been used to the creation of models by means of diminished methods. Two additive methods have been chosen: method of stereolithography (SLA) and also method of three-dimensional print (3DP). Research prototypes were manufactured by means of stereolitographic SLA-250 appliance production of 3D Systems Company and also three-dimensional print Z510 Spectrum printer production of Z Corporation. Manufactured casting models were researched under the angle of application to manufacturing ceramic casting forms. Analysis of described methods concerned determining of possibilities of application of presented methods for manufacturing of models of aircraft engines’ blades. There was determined also a range of application of presented methods on respective stages of technological process of manufacturing of models and casting forms for manufacturing of blades of aircraft engines’ turbine in process of mono- crystallization and also directional crystallization.

PL

Artykuł przedstawia analizę wybranych metod szybkiego prototypowania mających zastosowanie w procesie wytwarzania modeli odlewniczych łopatek silników lotniczych. Analizie zostały poddane metody przyrostowe oraz metoda ubytkowa. Do wykonania modeli metodą ubytkową została wykorzystana sterowana numerycznie (CNC) frezarka MDX-40 produkcji firmy Roland. Jako metody przyrostowe zostały wybrane: metoda stereolitografii (SLA) oraz metoda druku trójwymiarowego (3DP). Prototypy badawcze zostały wykonane za pomocą urządzenia stereolitograficznego SLA 250 produkcji 3D Systems oraz trójwymiarowej drukarki Z510 Spectrum produkcji Z Corporation. Wytworzone modele odlewnicze były przebadane pod kątem zastosowania do wykonywania ceramicznych form odlewniczych. Analiza opisanych metod polegała na określeniu możliwości zastosowania przedstawionych metod do wykonania modeli łopatek silników lotniczych. Określony został również zakres zastosowania przedstawionych metod na poszczególnych etapach procesu technologicznego wytwarzania modeli i form odlewniczych dla wytwarzania łopatek turbin silników lotniczych w procesie monokrystalizacji oraz krystalizacji kierunkowej.

17

Analysis of thermodynamic cycle influence of turbofan mixer engine on its performance

Jakubowski R.

Journal of KONES

|

2009

|

Vol. 16, No. 4

171-178

EN

The turbofan engines are widely used as propulsion of the contemporary airplanes. In the military application the turbofan mixer engines are used. Although the turbofan mixer engines are applied for a long time, the information about exact analysis of their thermodynamic cycle and performance are still in complete. The thermodynamic cycle of the turbofan mixer engine is presented and discussed in this paper. Based on it the cycle parameters selection is discussed. Then the optimization of turbofan mixer engine cycle is presented. Final results present the influence of chosen engine cycle parameters on the engine performance. The results are analyzed and discussed. On the basis of them the conclusions are formulated. It is not such an easy process to choose for the turbofan mixer engine thermodynamic parameters. It is connected with the fulfilment of two important rules. The equalization of total pressure of mixer inflow streamfor mixer efficient work is the first of it. The other rule is connected with engine cycle optimization. As it is shown it is not possible to choose engine parameters to reconcile the demands of specific thrust maximization and specific fuel consumption minimization. The engine thermodynamics parameters selection process is the search of the compromise between these two demand fulfilments, very often including engine mass analysis.

18

Comparison of internal processes effectiveness change influence the turbofan with and without mixer model sensitivity

Jakubowski R.

Journal of KONES

|

2008

|

Vol. 15, No. 3

201-207

EN

At the present time one of the way of the aircraft engines improvement is the fuel consumption reduction but the thrust should stay on the same level. One of the ways to realize this is the engine internal processes improvement. Nowadays technology and the commuter design methods allows us produce more efficient compressors, fans, turbines etc. To manage the proper process of engine improvement, it is demand to know how the chosen elements improvement influences the engine work parameters. This knowledge allows us to calculate the cost, and evaluate the effects of the improvements. In the paper, the analyzes of chosen internal engine process improvement influence on the specific thrust and the specific fuel consumption is done for turbofan engine. The processes effectives are characterized by flow losses coefficients and the processes efficiencies. In the beginning the two types of turbofan engine wit and without mixer is described. The main differences in the engines model are presented. Then the process effectiveness coefficients are defined and research method is presented. The analysis, based on the small deviation methods is use to calculate the results of the work. Then the results are presented as comparison graphs for the engine with the mixer and without the mixer. The results are analyzed and discussed. In the last parts of the paper the conclusion are presented.

PL

Współcześnie jedną z metod poprawy efektywności pracy silników lotniczych jest obniżanie jednostkowego zużycia paliwa, przy jednoczesnym niezmienianiu jego ciągu. Umożliwia to m.in. doskonalenie procesów wewnętrznych w silniku. Obecna technologia wytwarzania oraz komputerowe wsparcie procesów projektowania pozwala produkować zespoły silnika o coraz wyższej efektywności procesów wewnętrznych. Żeby optymalnie organizować proces podnoszenia efektywności pracy silnika wymagana jest znajomość wpływu modyfikacji efektywności poszczególnych zespołów na parametry użytkowe silnika. Umożliwia to oszacowanie kosztów i ocenę efektywności proponowanych modyfikacji silnika. W pracy przeprowadzono analizę wrażliwości modelu silnika dwuprzepływowego na zmianę efektywności procesów przepływowo-cieplnych w zespołach silnika. Efektywność procesów w zespołach silnika opisano poprzez wskaźniki strat ciśnienia oraz sprawności, zaś badanymi parametrami pracy silnika były ciąg jednostkowy i jednostkowe zużycie paliwa. Na początek scharakteryzowano dwa zasadnicze typy silników dwuprzepływowych - z mieszalnikiem i bez. Następnie przedstawiono przyjęty model silnika oraz wskaźniki oceny procesów wewnętrznych w zespołach i metodykę badań. W kolejnym kroku przeprowadzono badania z wykorzystaniem metod bazujących na metodzie małych odchyleń. Wyniki badań przedstawiono w postaci graficznej i omówiono porównując obydwie analizowane konstrukcje. Na koniec zaprezentowano wnioski do pracy.

19

Control law algorithms for aircraft engines and thrust management systems

Wiklik K.

Prace Instytutu Lotnictwa

|

2007

|

Nr 3 (190)

1-58

EN

The paper shows the control law algorithms for turbojet engines and thrust management systems and presents the simulation design method to find its settings, in order to fulfil the required performance criteria. The obtained results confirm that the simulation design approach has much to offer in the design of controls for next-generation engines and aircraft.

PL

W pracy podano algorytmy praw sterowania do turbinowych silników odrzutowych i układów zarządzania ciągiem. Przedstawiono metody symulacyjne umożliwiające określenie nastaw, które zapewniają spełnienie wymaganych kryteriów jakości sterowania. Otrzymane wyniki potwierdzają skuteczność metod symulacyjnych przy projektowaniu układów sterowania do silników i samolotów przyszłych generacji.

20

Investigation of the turbofan with mixer engine model sensitivity of thermal-flow process modification in the engine's components

Jakubowski R.

Journal of KONES

|

2007

|

Vol. 14, No. 4

119-126

EN

The turbofan with mixer engine model sensitivity of the thermal-flow processes effectiveness in the engine components changes was analyzed. The model of turbofan engine with the mixed exhaust stream is so complicated to use the small deviation methods to solve this problem. On that reason the own author methods to analyze this problem was proposed. During investigation it was revealed that the changes of some processes effectiveness leads to change of pressure inflow to the mixer and this cause to change of mixer process effectiveness. The mixer pressure drop coefficient decries so slightly but it should be taking into consideration during exact calculations. In the main parts of paper the results of simulation of engine work parameters sensitivity of the thermal-flow processes effectiveness changes is presented and discussed. The specific thrust and specific fuel consumption were chosen as the engine work parameters. The model responds for change of internal process effectiveness in all range and for small step was analyzed. The conclusions are presented in final parts of the paper. The essential influence on relations between the change of the efficiency of rotor sets and with specific parameters has compression rate of compressor. Generally the improvement performers of the excellence processes give better effects at the lower temperature value in front of the turbine.