Wyniki wyszukiwania - BazTech

1

Experimental study of dispersed flow in the thermopressor of the intercooling system for marine and stationary power plants compressors

Konovalov Dmytro, Kobalava Halina, Radchenko Mykola, Løvås Terese, Pavlenko Anatoliy, Radchenko Roman, Radchenko Andrii

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 1

art. no. e148439

EN

This study investigates the use of a thermopressor to achieve highly dispersed liquid atomization, with a primary focus on its application in enhancing contact cooling systems of the cyclic air for gas turbines. The use of a thermopressor results in a substantial reduction in the average droplet diameter, specifically to less than 25 μm, within the dispersed flow. Due to practically instantaneous evaporation of highly atomized liquid droplets in accelerated superheated air the pressure drop is reduced to minimum. A further increase of the air pressure takes place in diffuser. In its turn, this allows for the compensation of hydraulic pressure losses in the air path, thereby reducing compressive work. Experimental data uncover a significant decrease in the average droplet diameter, with reductions ranging from 20 to 30 µm within the thermopressor due to increased flow turbulence and intense evaporation. The minimum achievable droplet diameter is as low as 15 µm and accompanied by a notable increase in the fraction of small droplets (less than 25 µm) to 40–60%. Furthermore, the droplet distribution becomes more uniform, with the absence of large droplets exceeding 70 µm in diameter. Increasing the water flow during injection has a positive impact on the number of smaller droplets, particularly those around 25 μm, which is advantageous for contact cooling. The use of the thermopressor method for cooling cyclic air provides maximum protection to blade surfaces against drop-impact erosion, primarily due to the larger number of droplets with diameters below 25 μm. These findings underline the potential of a properly configured thermopressor to improve the efficiency of contact cooling systems in gas turbines, resulting in improved performance and reliability in power generation applications. The hydrodynamic principles explored in this study may have wide applications in marine and stationary power plants based on gas and steam turbines, gas and internal combustion engines.

2

Elements of supercritical CO2 cycle - mathematical modeling and validation on available experimental data

Milewski Jarosław, Szczęśniak Arkadiusz, Szablowski Łukasz, Futyma Kamil, Lis Piotr, Dybiński Olaf, Wołowicz Marcin

Journal of Power Technologies

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2022

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Vol. 102, nr 1

1--13

EN

This paper presents models of three elements: heat exchanger, compressor and expander dedicated to supercritical CO2 cycles (Brayton). The models are built using Ebsilon software and validated against experimental data from available literature. Radial turbomachinery and thin plate heat exchangers were used to meet the demands of the relatively compact design of the S-CO2 cycle elements. It seems that there are no general relationships for the turbomachinery and real characteristics need to be used for constructing the models.

3

Engineering design of a manipulator for mounting an air suspension compressor to a car chassis

Blatnický Miroslav, Dižo Jan, Barta Dalibor, Rybicka Iwona

Zeszyty Naukowe. Transport / Politechnika Śląska

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2020

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z. 109

5--16

EN

This article is aimed at the engineering design of a manipulator, which is pneumatically controlled. It will serve for mounting the compressor of an air suspension system to the chassis of a sport utility vehicle (SUV) produced in the Slovak Republic. The manipulator will be used on an assembly line, on which SUVs are assembled. The designed device belongs to a group of dedicated devices, which are not produced within a serial production, however, it is the only functional prototype. Together with the manipulator structure, a pneumatic part of the assembly line including individual components, schemes and the pneumatic system will be proposed. Within the project process, all necessary customer demands, technical and safety standards have to be met. Moreover, ergonomic requirements for handling the device and other acts on the workplace have to be considered.

4

Time-frequency analysis of the surge onset in the centrifugal blower

Liśkiewicz G., Horodko L.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2014

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nr 145

81--84

EN

Time frequency analysis of the surge onset was performed in centrifugal blower. Pressure signal was registered at the blower inlet, blower outlet and three locations at the impeller shroud. The time-frequency scalograms were obtained by means of the Continuous Wavelet Transform (CWT). The blower was found to successively operate in four different conditions: stable working conditions, inlet recirculation, transient phase and the deep surge. Scalograms revealed different spectral structure of aforementioned phases and suggest possible ways of detecting the surge predecessors.

5

Radial compressor unstable operation modelling

Polansky J., Hocko M.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2014

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nr 145

97--98

EN

Unstable operation of a compressor is a dangerous phenomenon which occurs during certain operating regimes of compressors in engine turbo-compressors and also in combustion turbines used in transport and stationary energetics equipment. It is manifested by a sudden change of pressure and speed of air flow at the output of the compressor and characteristic sounds, which result in intense vibration of the rotor blades and changes to the character of air flow in other parts of the device. Surge or stall can result in interruption of engine operation, or its destruction due to mechanical damage to the compressor blades or heat damage to the blades of the gas turbine. This is why the formation of unstable compressor modes is inadmissible and a great deal of attention is devoted to preventing it.

6

Dynamical system analysis of unstable flow phenomena in centrifugal blower

Garcia D., Stickland M., Liśkiewicz G.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2014

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nr 145

43--46

EN

Methods of dynamical system analysis were employed to analyze unsteady phenomena in the centrifugal blower. Pressure signals gathered at different control points were decomposed into their Principal Components (PCs) by means of Singular Spectrum Analysis (SSA). Certain number of PCs was considered in the analysis based on their statistical correlation. Projection of the original signal onto its PCs allowed to draw the phase trajectory that clearly separated non-stable blower working conditions from its regular operation.

7

Investigation of Design Features of Compressor Casing Treatment

Nezym V

Archive of Mechanical Engineering

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2014

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Vol. LXI, nr 1

153--161

EN

Obróbka obudowy kompresora, polegajacą na wykonaniu obwodowych rowków ponad szczytem łopaty wirnika, jest stosowana dla poprawy własciwosci roboczych kompresora. Zwykle rowki takie zwiekszaja zakres przeciagania kompresora (zakres stabilnego działania), ale pogarszaja sprawność. W artykule zaprezentowano główne wyniki badan nad rowkami, które wpływaja pozytywnie na sprawnosc kompresora. Badano zarówno tradycyjne (typowe) konfiguracje rowków, jak i konfiguracje ostatnio opracowane. Niektóre z nich zapewniają zarówno wzrost sprawności jak zakresu przeciągania.

8

The concept of type-series and design of centrifugal compressors

Grzelczak M., Walczak J., Grudziński M.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2011

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nr 140

91-96

EN

The paper presents analyses constituting a part of design works connected with development of series of types and structures of radial compressors. Radial compressors are multi-stage and multi-shaft flow machines with unshrouded radial impellers. Preliminary analyses based upon the theory of flow similarity related to a concept of series of types of compressors and were aimed at establishment of particular sizes of series of types of the machines as well as sizes of particular stages. The analyses aimed at determination of various sizes of rotor diameters and rotational speeds used in particular stages. The analysis was aimed at standardization of elements that may be used in structures of stages of machines of various sizes with maintenance of the high level of compression efficiency.

9

Application of supersonic ejectors for hydrocarbon emissions capture

Biba Y., Kidd H. A., Peifer S., Scott Ch., Sloof B., Tse A.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2011

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nr 140

39-52

EN

Supersonic ejectors capturing low-pressure leakage gas from the compressors gas seal vents and re-injecting it into the fuel gas line of the gas generator allow not only saving the gas that otherwise would be leaking to the atmosphere but also eliminate hydrocarbon emissions. There are also operational and maintenance benefits, as the supersonic ejector itself does not have moving parts and is inherently maintenance free. A prototype design was developed and tested at a pipeline compressor station. A family of three ejectors was designed to cover a range of operating conditions associated with gas turbine driven compressors in pipeline applications. These ejectors were built, installed on the specially designed panel and tested at the Dresser-Rand facility. A comparison of predicted and as-tested operating maps is discussed and conclusions are made about operating range.

10

Analysis of the flow gas in a compressor impeller on the basis of velocity measurements with the use of LDA laser anemometer

Grzelczak M.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2011

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nr 140

73-82

EN

This study presents results of tests on the structure of gas flow through a compressing stage of a radial blower. The tests conducted used LDA laser anemometer enabling measurement of velocities in diversified geometries such as, among others, geometries of the compressor rotors. The presented measurement results relate to a half-open axial and radial rotor, for which velocity field s were obtained in two control cross-sections, i.e. in the inlet cross-section and outlet cross-section. The obtained results enabled an evaluation of the effectiveness of the adopted design solutions.

11

Modernization of a nitrous gas turbine-driven turbocompressor

Kryłłowicz W., Kozanecki Z., Świder P.

Mechanics and Mechanical Engineering

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2011

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Vol. 15, nr 3

289-296

EN

The modernization of a nitrous gas four-stage centrifugal compressor is presented. The assumptions for modernization, its methodology and the results of thermodynamical, flow and dynamical calculations have been discussed. The technological aspects of the rotor modernization have been given.

12

Modernizacia sistemy uplotnitel'nogo masla kompressorov sintez-gaza poz. 103J

Loza A.

Zeszyty Naukowe Politechniki Świętokrzyskiej. Nauki Techniczne

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2008

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Z. 10, Vol. 2

255-257

EN

This article describes the necessity of sealing oil system of synthesis - gas compressors - pos. 103J of ammonia production modernization, by replacement of actual plunger pumps on a screw pumps. This article specifies the advantages of such replacement.

13

Stator clocking in SO3 compressor first stage rotor blades

Rządkowski R, Gnesin V, Kolodyazhnaya L, Szczepanik R

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2008

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nr 133

299--308

EN

Numerical calculations of the 3D transonic flow of an ideal gas through three-row compressor stage including the clocking effects are presented. The approach is based on the solution of the coupled aerodynamic-structure problem for the 3D flow through the turbine stage in which fluid and dynamic equations are integrated simultaneously in time. There has been performed the calculation for the stage of the compressor with rotor blades of 0.163 m. The aeroelastic characteristics are obtained for different position of the stator rows. The clocking effect influence the stability region of the rotor blades.

14

Tłocznia gazu ziemnego w Systemie Gazociągów Tranzytowych Jamał - Europa

Gerwatowski D.

Nowoczesne Gazownictwo

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2006

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nr 1

27-32

15

Nie zawsze CAD-CAM. Program "FREZ"

Zniszczyński A.

Mechanik

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2004

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R. 77, nr 5-6

414-416

EN

Presented there is description of production of a quadruple rotary piston air compressor prototype for which a unique FREZ software had been developed for opertion of a five spindle milling machine.

16

Rekonfigurowalny koprocesor systemowy: uniwersalna platforma obliczeniowa

Jasiński K., Zbysiński P.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2000

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R. 73, nr 10

760-766

PL

Przedstawiono zwięzły przegląd architektur rekonfigurowalnych systemów obliczeniowych i na tym tle zaprezentowano własne rozwiązanie prototypowej platformy rekonfigurowalnego akceleratora obliczeń. Opis konstrukcji sprzętowo-programowej platformy zilustrowano przykładami aplikacji z dziedziny kryptografii i naszkicowano plan dalszej rozbudowy platformy przy użyciu modułów rozszerzających typu piggy-back.

EN

The architectures of reconfigurable computational systems are concisely reviewed and own prototype of reconfigurable computation accelerator platform is presented. The presentation of the hardware-software platform is illustrated with applications to cryptography. The perspective of further development of the platform using piggy-back extension modules is also given.

17

3-D characteristics of turbulent wakes behind rotor of axial flow low speed compressor stage

Witkowski A., Chmielniak T., Strozik M., Majkut M., Żukowski J.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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1999

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nr 115

457--468

EN

The threedimensional unsteady flow field downstream of the rotor in a single-stage low speed axial flow compressor at four operating conditions has been investigated experimentally using both straight and 900 triple split fiber probes with an emphasis on the influence of the compressor load on the rotor wake characteristics. The velocity measurements are decomposed into a time average velocity, a periodic velocity component, and an unresolved velocity component. Results are discussed to understand the flow effect depending on the operation point and particularly near the stability line of a compressor.