scholarly journals Працездатність підшипників ковзання як опор шестерень основного паливного насосу ГТД

2021 ◽  
pp. 52-58
Author(s):  
Олександр Віталійович Білогуб ◽  
Ігор Сергійович Романенко ◽  
Олександр Володимирович Гудошник ◽  
Сергій Олександрович Тристан
Keyword(s):  
Gas Turbine ◽  
Residual Life ◽  
Load Capacity ◽  
Limiting Factors ◽  
Working Fluid ◽  
Gear Pump ◽  
Minimum Thickness ◽  
Shaft Length ◽  
Low Viscosity ◽  
Viscous Shear

The paper is about the performance capability of the journal bearings as a support of the fuel gear pump for gas turbine engines (GTE). Supports of the external gear pump usually operate in semi-dry friction conditions, which reduces residual life and is one of the limiting factors. For this investigation, the serial gear pump was chosen with the following parameters: the number of teeth z = 14, module m = 3.8, gear-loading Р = 7800 N. The authors have studied options for a pump with an electrical and mechanical (from the rotor of the GTE) drive. The main criterion for studying the bearing capacity is the minimum thickness of the working layer of a fluid with low viscosity (kerosene). For modeling, a common theory is used based on solutions of differential equations of the viscous fluid hydrodynamics, which relate pressure, velocity, and viscous shear resistance. For technological reasons, the minimum allowable kerosene layer is limited to 5 μm. The conducted analysis considers the multi-lobe (2-, 3- and 4-lobe) bearings with different lobe orientations relative to the force vector. It was found that the 2-lobe bearing has the best load capacity (provides the largest layer of kerosene). According to the results of the previous investigation for further work, the 2-lobe bearing was chosen. The influence of load, setting gap, eccentricity, the specific radius of lobe curvature, shaft length on the bearing load capacity was analyzed. A rational type of bearing design was proposed based on the load capacity criterion (the minimum layer of working fluid). It was shown that the hydrodynamic 2-lobe bearing can be sufficiently effective for the supports of the gear fuel pumps of GTE. Based on the results of the investigation, 2 variants of the pumping unit designs were proposed. The first one for the pump driven by the gas turbine engine rotor with parameters z = 19, m = 3.3, gears width B = 34, shaft diameter DS = 48, and shaft length LS = 56 (P = 10.2kN). The second one for the electrically driven pump, z = 28, m = 1,8, B = 15, DS = 34, and LS = 41 (P = 3.8 kN). The minimum angular velocity for the pump variants is 470 and 1055 rad/s, respectively. According to the investigation results, it was proposed to conduct related studies of the working process in pumps and bearings.

A General-Purpose Test Facility for Evaluating Gas Lubricated Thrust Bearings

2020 ◽  
Author(s):  
Keith Gary ◽  
Bugra Ertas ◽  
Adolfo Delgado
Keyword(s):  
Gas Turbines ◽  
High Performance ◽  
Load Capacity ◽  
General Purpose ◽  
Test Facility ◽  
Working Fluid ◽  
Test Rig ◽  
Auxiliary Equipment ◽  
Thrust Bearings ◽  
Low Viscosity

Abstract The design, construction, operational capabilities, and proof of concept results are presented for a test rig used to evaluate gas-lubricated thrust bearings. The following work is motivated by a desire to utilize the working fluid of high-performance turbomachinery, such as gas turbines, for bearing lubricant. Auxiliary equipment required to cool, pump, and clean oil for a typical thrust bearing is eliminated by taking advantage of the turbomachinery’s working fluid as bearing lubricant. The benefit of removing such auxiliary equipment is obvious when considering cost and weight of turbomachines, yet the working fluid of gas turbines typically has very low viscosity compared to oil which introduces load capacity and stability challenges. It is therefore necessary to build a facility capable of testing gas-lubricated thrust bearings to advance the technology. The test rig design in this work allows for 7 to 15 inch (180–380 mm) diameter thrust bearings, static loads up to 30,000 lbf (135 kN), and speeds up to 20 krpm. The test facility also provides up to 500 psig (3.45 MPa) static air pressure to enable testing of hydrostatic and hybrid (hydrodynamic combined with hydrostatic) bearings. This paper describes the test rig operating principle, details experimental procedures to obtain measurements, and provides test results necessary to prove the test rig concept by means of a hybrid gas bearing.

Causes of gear pump fails and methods for their elimination

2020 ◽  
pp. 98-107
Author(s):  
Vitaliy A. Zuyevskiy ◽  
Daniil O. Klimyuk ◽  
Ivan A. Shemberev
Keyword(s):  
Adhesion Strength ◽  
Production Systems ◽  
Low Cost ◽  
High Strength ◽  
Strength Properties ◽  
Research Purpose ◽  
Working Fluid ◽  
Gear Pump ◽  
Repair Service ◽  
Recovery Method

Gear pumps are an important element of many production systems and their replacement in case of failure can be quite expensive, so it is important to have a modern and well-tuned technology for their recovery. There are many methods for restoring the pump's performance, depending on the reason that led to its failure. (Research purpose) The research purpose is in determining what causes most often lead to loss of pump performance, and developing a recovery method that provides the greatest post-repair service life of the pump and low cost of repair. (Materials and methods) Authors took into account that the applied coatings must have sufficient adhesion strength and resistance to mechanical, thermal and corrosion loads during operation. It was found that most often significant leaks of the working fluid, leading to failure, occur due to an increase in the gap between the inner surface of the housing and the gears due to active wear of the housing wells. Authors determined that the method of electric spark treatment of worn-out housing wells is best suited to perform the task (a large post-repair resource and low costs). (Results and discussion) It was found by laboratory studies of the adhesion strength of electric spark coatings with various electrodes that the best transfer of the material to the substrate is provided by bronze electrodes BrMKts3-1. It was noted that the coatings applied using the BrMKts3-1 electrode have high strength properties. (Conclusions) Research conducted in the center for collective use "Nano-Center" VIM confirmed the possibility of effective recovery of the gear pump by electric spark treatment.

Experimental Study of a 200 kW Partial Oxidation Gas Turbine (POGT) for Co-Production of Power and Hydrogen-Enriched Fuel Gas

2009 ◽  
Author(s):  
Joseph Rabovitser ◽  
Stan Wohadlo ◽  
John M. Pratapas ◽  
Serguei Nester ◽  
Mehmet Tartan ◽  
...  
Keyword(s):  
Experimental Study ◽  
Gas Turbine ◽  
Partial Oxidation ◽  
Synthesis Gas ◽  
Combustion Products ◽  
Working Fluid ◽  
Fuel Gas ◽  
Lean Combustion ◽  
Start Up ◽  
Oxidation Reactor

Paper presents the results from development and successful testing of a 200 kW POGT prototype. There are two major design features that distinguish POGT from a conventional gas turbine: a POGT utilizes a partial oxidation reactor (POR) in place of a conventional combustor which leads to a much smaller compressor requirement versus comparably rated conventional gas turbine. From a thermodynamic perspective, the working fluid provided by the POR has higher specific heat than lean combustion products enabling the POGT expander to extract more energy per unit mass of fluid. The POGT exhaust is actually a secondary fuel gas that can be combusted in different bottoming cycles or used as synthesis gas for hydrogen or other chemicals production. Conversion steps for modifying a 200 kW radial turbine to POGT duty are described including: utilization of the existing (unmodified) expander; replacement of the combustor with a POR unit; introduction of steam for cooling of the internal turbine structure; and installation of a bypass air port for bleeding excess air from the compressor discharge because of 45% reduction in combustion air requirements. The engine controls that were re-configured for start-up and operation are reviewed including automation of POGT start-up and loading during light-off at lean condition, transition from lean to rich combustion during acceleration, speed control and stabilization under rich operation. Changes were implemented in microprocessor-based controllers. The fully-integrated POGT unit was installed and operated in a dedicated test cell at GTI equipped with extensive process instrumentation and data acquisition systems. Results from a parametric experimental study of POGT operation for co-production of power and H2-enriched synthesis gas are provided.

Multi-Fluid Gas Turbine Components Scaling for a Generation IV Nuclear Power Plant Performance Simulation

2018 ◽  
Author(s):  
Emmanuel O. Osigwe ◽  
Arnold Gad-Briggs ◽  
Theoklis Nikolaidis ◽  
Pericles Pilidis ◽  
Suresh Sampath
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Gas Turbine ◽  
Nuclear Power ◽  
Working Fluid ◽  
Simulation Tool ◽  
Closed Cycle ◽  
Performance Simulation ◽  
Working Fluids ◽  
Component Map

One major challenge to the accurate development of performance simulation tool for component-based nuclear power plant engine models is the difficulty in accessing component performance maps; hence, researchers or engineers often rely on estimation approach using various scaling techniques. This paper describes a multi-fluid scaling approach used to determine the component characteristics of a closed-cycle gas turbine plant from an existing component map with their design data, which can be applied for different working fluids as may be required in closed-cycle gas turbine operations to adapt data from one component map into a new component map. Each component operation is defined by an appropriate change of state equations which describes its thermodynamic behavior, thus, a consideration of the working fluid properties is of high relevance to the scaling approach. The multi-fluid scaling technique described in this paper was used to develop a computer simulation tool called GT-ACYSS, which can be valuable for analyzing the performance of closed-cycle gas turbine operations with different working fluids. This approach makes it easy to theoretically scale existing map using similar or different working fluids without carrying out a full experimental test or repeating the whole design and development process. The results of selected case studies show a reasonable agreement with available data.

Optimization of Advanced Liquid Natural Gas-Fuelled Combined Cycle Machinery Systems for a High-Speed Ferry

2012 ◽  
Author(s):  
Kari Anne Tveitaskog ◽  
Fredrik Haglind
Keyword(s):  
Gas Turbine ◽  
High Speed ◽  
Dynamic Network ◽  
Combined Cycle ◽  
Working Fluid ◽  
Power Requirement ◽  
Pressure Steam ◽  
Combined Cycles ◽  
Liquid Natural Gas ◽  
Steam Cycle

This paper is aimed at designing and optimizing combined cycles for marine applications. For this purpose, an in-house numerical simulation tool called DNA (Dynamic Network Analysis) and a genetic algorithm-based optimization routine are used. The top cycle is modeled as the aero-derivative gas turbine LM2500, while four options for bottoming cycles are modeled. Firstly, a single pressure steam cycle, secondly a dual-pressure steam cycle, thirdly an ORC using toluene as the working fluid and an intermediate oil loop as the heat carrier, and lastly an ABC with inter-cooling are modeled. Furthermore, practical and operational aspects of using these three machinery systems for a high-speed ferry are discussed. Two scenarios are evaluated. The first scenario evaluates the combined cycles with a given power requirement, optimizing the combined cycle while operating the gas turbine at part load. The second scenario evaluates the combined cycle with the gas turbine operated at full load. For the first scenario, the results suggest that the thermal efficiencies of the combined gas and steam cycles are 46.3% and 48.2% for the single pressure and dual pressure steam cycles, respectively. The gas ORC and gas ABC combined cycles obtained thermal efficiencies of 45.6% and 41.9%, respectively. For the second scenario, the results suggest that the thermal efficiencies of the combined gas and steam cycles are 53.5% and 55.3% for the single pressure and dual pressure steam cycles, respectively. The gas ORC and gas ABC combined cycles obtained thermal efficiencies of 51.0% and 47.8%, respectively.

Modeling and Analysis of Power Conversion System for High Temperature Gas Cooled Reactor With Cogeneration

2008 ◽  
Author(s):  
Ali Afrazeh ◽  
Hiwa Khaledi ◽  
Mohammad Bagher Ghofrani
Keyword(s):  
High Temperature ◽  
Heat Source ◽  
Gas Turbine ◽  
Power Conversion ◽  
Hot Water ◽  
Working Fluid ◽  
Closed Cycle ◽  
Nuclear Heat ◽  
Conversion System ◽  
High Temperature Gas

A gas turbine in combination with a nuclear heat source has been subject of study for some years. This paper describes the advantages of a gas turbine combined with an inherently safe and well-proven nuclear heat source. The design of the power conversion system is based on a regenerative, non-intercooled, closed, direct Brayton cycle with high temperature gas-cooled reactor (HTGR), as heat source and helium gas as the working fluid. The plant produces electricity and hot water for district heating (DH). Variation of specific heat, enthalpy and entropy of working fluid with pressure and temperature are included in this model. Advanced blade cooling technology is used in order to allow for a high turbine inlet temperature. The paper starts with an overview of the main characteristics of the nuclear heat source, Then presents a study to determine the specifications of a closed-cycle gas turbine for the HTGR installation. Attention is given to the way such a closed-cycle gas turbine can be modeled. Subsequently the sensitivity of the efficiency to several design choices is investigated. This model is developed in Fortran.

Modelling and Simulation of Transient Performance of the Semi-Closed O2/CO2 Gas Turbine Cycle for CO2-Capture

2003 ◽  
Author(s):  
Ragnhild E. Ulfsnes ◽  
Olav Bolland ◽  
Kristin Jordal
Keyword(s):  
Water Vapor ◽  
Specific Heat ◽  
Gas Turbine ◽  
Transient Behavior ◽  
Cycle Performance ◽  
Working Fluid ◽  
Transient Event ◽  
Co2 Gas ◽  
Specific Heat Ratio ◽  
Gas Turbine Cycle

One of the concepts proposed for capture of CO2 in power production from gaseous fossil fuels is the semi-closed O2/CO2 gas turbine cycle. The semi-closed O2/CO2 gas turbine cycle has a near to stoichiometric combustion with oxygen, producing CO2 and water vapor as the combustion products. The water vapor is condensed and removed from the process, the remaining gas, primarily CO2, is mainly recycled to keep turbine inlet temperature at a permissible level. A model for predicting transient behavior of the semi-closed O2/CO2 gas turbine cycle is presented. The model is implemented in the simulation tool gPROMS (Process System Enterprise Ltd.), and simulations are performed to investigate two different issues. The first issue is to see how different cycle performance variables interact during transient behavior; the second is to investigate how cycle calculations are affected when including the gas constant and the specific heat ratio in compressor characteristics. The simulations show that the near to stoichiometric combustion and the working fluid recycle introduce a high interaction between the different cycle components and variables. This makes it very difficult to analytically predict the cycle performance during a transient event, i.e. simulations are necessary. It is also found that, except for the shaft speed calculation, the introduction of gas constant and specific heat ratio dependence on the compressor performance map will have only a minor influence on the process performance.

Second Law Efficiency of an Intercooled-Reheated-Regenerative-Brayton Cycle With Variable Temperature Heat Reservoirs

2012 ◽  
Author(s):  
Vishal Anand ◽  
Krishna Nelanti ◽  
Kamlesh G. Gujar
Keyword(s):  
Gas Turbine ◽  
Variable Temperature ◽  
Pressure Ratio ◽  
Working Fluid ◽  
Thermodynamic Efficiency ◽  
Second Law ◽  
Brayton Cycle ◽  
Cooling Fluid ◽  
Turbine Engine ◽  
Temperature Heat

The gas turbine engine works on the principle of the Brayton Cycle. One of the ways to improve the efficiency of the gas turbine is to make changes in the Brayton Cycle. In the present study, Brayton Cycle with intercooling, reheating and regeneration with variable temperature heat reservoirs is considered. Instead of the usual thermodynamic efficiency, the Second law efficiency, defined on the basis of lost work, has been taken as a parameter to study the deviation of the irreversible Brayton Cycle from the ideal cycle. The Second law efficiency of the Brayton Cycle has been found as a function of reheat and intercooling pressure ratios, total pressure ratio, intercooler, regenerator and reheater effectiveness, hot and cold side heat exchanger effectiveness, turbine and compressor efficiency and heating capacities of the heating fluid, the cooling fluid and the working fluid (air). The variation of the Second law efficiency with all these parameters has been presented. From the results, it can be seen that the Second law efficiency first increases and then decreases with increase in intercooling pressure ratio and increases with increase in reheating pressure ratio. The results show that the Second law efficiency is a very good indicator of the amount of irreversibility of the cycle.

Description of an Operating Closed Cycle: Helium Gas Turbine

1963 ◽  
Author(s):  
James K. La Fleur
Keyword(s):  
Gas Turbine ◽  
Working Fluid ◽  
Refrigeration Cycle ◽  
Preliminary Design ◽  
Closed Cycle ◽  
Helium Gas ◽  
Compressor Inlet ◽  
Last Stage ◽  
Low Temperature Refrigeration ◽  
Made In

In May of 1960 La Fleur Enterprises, later to become The La Fleur Corporation, undertook the design of a closed-cycle gas turbine utilizing helium as a working fluid. The useful output of this machine was to be in the form of a stream of helium bled from the last stage of the compressor. This stream was to be used in a low-temperature refrigeration cycle (not described in this paper) and would be returned to the compressor inlet at approximately ambient temperature and at compressor-inlet pressure. The design of this machine was completed by the end of 1960 and construction was initiated immediately. The unit was completed and initial tests were made in the Spring of 1962. This paper covers the design philosophy as it affected the conceptual and preliminary design phases of the project and describes briefly the design of the various components. Photographs of these components and a flow schematic are included.

scholarly journals The Design of Turbomachinery for the Gas Turbine (Direct Cycle) High Temperature Gas Cooled Reactor Power Plant

1977 ◽  
Author(s):  
R. G. Adams ◽  
F. H. Boenig
Keyword(s):  
High Temperature ◽  
Power Plant ◽  
Gas Turbine ◽  
Power Conversion ◽  
Reactor Power ◽  
Working Fluid ◽  
Primary Coolant ◽  
Reactor Power Plant ◽  
Direct Cycle ◽  
High Temperature Gas

The Gas Turbine HTGR, or “Direct Cycle” High-Temperature Gas-Cooled, Reactor power plant, uses a closed-cycle gas turbine directly in the primary coolant circuit of a helium-cooled high-temperature nuclear reactor. Previous papers have described configuration studies leading to the selection of reactor and power conversion loop layout, and the considerations affecting the design of the components of the power conversion loop. This paper discusses briefly the effects of the helium working fluid and the reactor cooling loop environment on the design requirements of the direct-cycle turbomachinery and describes the mechanical arrangement of a typical turbomachine for this application. The aerodynamic design is outlined, and the mechanical design is described in some detail, with particular emphasis on the bearings and seals for the turbomachine.

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