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Numerical simulation of a two-stage turbine for turbopumps of liquid propellant rocket engine.Fernando Cesar Ventura Pereira 00 December 1999 (has links)
The main aim is to understand the gas dynamic process, which occurs inside a two-stage turbine and to propose an algorithm for the simulation of a two-stage turbine at design and off-design points. The explanation of each chapter is constructed to make further works easy, which should be the main of any research work that needs to be continued. Moreover, the structure of the chapters is organized in order to expose the theory in a progressive order, avoiding confusing references to preceding topics. According to this method, the content of each chapter is showed in following topics. The Introduction explains the main goals of the Brazilian Space Agency (AEB), focusing the launching vehicle. Chapter II describes a two-stage impulse turbine designed for a liquid rocket engine and some trubopump basic design criteria. A detailed description of the main losses in two-stage axial turbines of liquid propellant rocket engine is depicted in Chapter III. The explanation are always associated with Russian experimental results showed in graphics or equations relating physical variables neasurable in experiments, and dimensionless factors of losses and efficiency. Experimental evidences have been used to produce experimental equations for the determination of the magnitude of the losses and flow angles in blade rows. Several design solution proposed in Chapter IV for improving the efficiency are based on empirical data. Then, some concepts are introduced in designing gas turbines as: power Nu' specific work Lu'load coefficient Lu.ratio and efficiency hu as function of the ratio of the tangential speed u to the adiabatic speed cad for single-stage an two-stage turbines and turbine specific work LT, turbine load coefficient LT.ratio' overall turbine efficiency hT and turbine power NT as function of the ratio of the tangential speed u to the adiabatic speed cad for two-stage turbines. The flow through nozzles and blade rows is examined in detail in Chapter V, where the process of gas expansion in cascades and features of the flow over blade surfaces are described for subsonic, transonic and supersonic conditions. In Chapter V, it is also discussed the structure of the boundary layer in order to reveal the general laws governing the flow around of blades and the methods used for designing blade profiles to lower shock waves. In the first topic of Chapter VI, the initial parameters of turbine calculations are slected and its values are defined according to initial data analysis. In the second topic, the dimensionless criteria for similarity of gas turbine are described. The basic parameters and the dimensionless criteria for similarity of gas turbine allow the definition of the mass flow and energy charactiristics of the turbines. Special attention is devoted to particular characteristics of high and low-pressure turbines. The relations explained in the preceding chapters are used for implementation of a computer program, using software "Mathcad" for simulation of the turbine working at design and off-design conditions. The algoritms for one and two axial impulse turbines are saved in the files I.mcd and II.mcd respectively in the CD-ROM. The appendix only shows the output data for two-stage axial impulse turbines. In Chapter 7, the validation of the methodology and the computer program is done using test data from Russian bipropellant (kerosene and liquid oxygen) engine RD - 0109 for the design point and using general empirical relations, obtained from linear regression of test data of actual one and two-stage axial impulse turbines for off-design points.
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Genomgång av Turbomin 100 : Förstudie och föreslagna förbättringar av undervisningsjetmotor Turbomin 100Lilliesköld, Anders January 2010 (has links)
ABSTRACT This project thesis has been written at the request of Mälardalens University, Västerås. The aeronautical engineering students at Mälardalens University and the pupils of Hässlö upper secondary school, all gets the opportunity to perform a computation lab with a real turbojet engine during their study. The goal of the lab from the University is that it should give the students applied experience from the theory part of which has been tought in the course “Aircraft Engine Technology”. The pupils of the Hässlö upper secondary school are performing simpler calculations from the measured values of the equipment. This turbojet engine is located at Hässlö airport in the premises of Hässlö upper seconday school. Since the installation 1989, the engine has lost both thrust and reliability. This makes the theoretical computations made by the students inaccurate. Computations don’t match up with measured values. Also if the engine is inoperational, that would affect the education adversely. The purpose of this project thesis is to find a suitable upgrade solution both economically and practically. The thesis was divided into three different bullet points: Find the costings to renovate the existing Turbomin 100 turbojet engine. Also to find a suitable upgrade of the presentation of the measuring instruments to better clarify the lab. Motivate the disadvantages and the benefints respectively. Find the costings to source new lab equipment matching the Turbomin 100 equipment and motivate why this would improve the lab. This purchase doesn’t need to be a purchase of an off-the-shelf solution, but can also imply the development of an inhouse solution. Motivate the disadvantages and the benefints respectively. Develop a new lab instruction which matching one of the choosen alternatives above. This study results in several solutions: Proposal 1: The existing Turbomin 100 has such a solid construction that only a few spare parts needs to be replaced to get its original characteristics back. The use of measure equipment from Campbell Scientific consisting of a datalogger and associated software makes the presentation possible on a computer, from which printing easily can be done. This type of presentation would improve the understanding amongst the students for where and why the measurements are being made in certain areas of the engine. Estimated price for this solution is: 46.060 kr Proposal 2: New lab equipment could consist of two different solutions. The first solution is to invest in two turbojet engines from JetCat with a thrust of 80N each. Having two engines would ensure the operations by having one operational and the other one as a spare when its time for the compulsory service after 50 hours of run time. This solution together with the above mentioned solution for measure equipment including pressure and temperature probes would cost around 104.300 kr.Another solution would be to invest in a complete engine and measure equipment from Turbine Technologies. Their turbojet engine comes in a test cabinet with all probes and instrument installed. Even a computer can be connected to get readings digitally. This makes it possible to print or even save the measured values. Quoted price for this solution is between 412.700 and 766.700 kr depending on solution. Recommended solution from above is Proposal 1 will the new lab instructions look like attachment H.
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Převodovka mobilní elektrocentrály / Gearbox for portable power generatorKolka, Roman January 2008 (has links)
The submitted project deals with a complete design of a gearbox of a portable ground power generator designed for preflight preparation of helicopters. The gearbox has been designed to meet given specifications, which are based on required electrical parameters of the entire power unit and with regards to parameters of driving turbine engine. The introductory section deals with a kinematical design of transmission gears with regards to required parameters and design constraints. The kinematical design determines whole concept and resulting form of the gearbox. Next part deals with optimization of gearing, the design of wheel bearing, and design of oil system. The implementation part of the project consists in the engineering design of the gearbox, which was made in 3D environment Pro/Engineer. The design is reviewed and first operational results of manufactured and tested gearbox are discussed in the concluding section of this work.
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