Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: turbine nozzle

Sortuj według:

Ogranicz wyniki do:

Theoretical studies of variable geometry : hot section of the miniature jet engine

Chmielewski M., Fulara S., Gieras M.

Journal of KONES

2016

Vol. 23, No. 2

69--80

The aim of this article is to present the results of theoretical studies regarding the use of variable geometry hot section of a miniature gas turbine. The variable geometry combustor and variable area nozzle concepts for GTM-120 miniature jet engine are presented in particular. Recent trends of propulsion system size reduction, low-emission combustion and improved fuel efficiency have been considered. A system of variable geometry combustor and variable area nozzle has been proposed as solution. The basic zero-dimensional analytical models for variable geometry combustor and variable area nozzle are developed. Chemkin based model shows significant NOX/CO emissions reduction and combustor outlet enthalpy increases with the use of variable geometry combustor chamber. The analytical model of the variable area nozzle has been proposed. It shows turbine effectiveness increase across its operating range by raising the compressor working line. As a result, noticeable turbine stage efficiency increase has been obtained. Finally, physical implications and future work plans regarding variable geometry hot section of miniature gas turbines are discussed.

Qualitative comparison of 2D and 3D computation of flow field in the cone shaped turbine nozzle

Puzyrewski R., Flaszyński P.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

2000

Vol. 4, No 2

179-192

The paper presents a qualitative comparison of 2D and 3D computation of the flow field in a cone shaped turbine nozzle. The calculation yields a surface, S/sub 2/, for a given conical stream surface S/sub 1/. The S/sub 2/ stream surface represents the curvature of blading passages. This formulation is typical for the inverse problem. Based on a surface it is possible to design the shape of the blade. Results of 3D computation by means of FLUENT have been presented and compared with assumptions in the 2D model.

Methods of design modifications of turboprop and turboshaft engines

Antas S.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

1999

nr 115

9--20

This paper presents shortly reasons of improving designs and de scribes general methods of making moditications of turboprop and turboshaft engines. The theoretical analysis of methods of modifying, concerning general changes of efficiency, flow, and rating. So, the influence of the following factors on engine performance was presented: change of quality unit functioning factors, increase of compression and flow rate by using a compressor zero-stage; changes of gas temperature keeping the gasgenerator rotational speed by adjusting the minimal throat area of turbine nozzle guide vanes; modelling; and changes of rotational speeds of operational ratings.