Gas Turbine Units Research Articles

Investigation of Biomass Integrated Air Gasification Regenerative Gas Turbine Power Plants

The results show that Wood Chips of Acacia Nilotica trees available in Sudan lands can be successfully used in the gasification process and, on the same basis, as a bio-renewable energy resource. Simulation models were used to characterize the air gasification process integrated with a Regenerative Gas Turbine Unit. The results revealed that at a moisture content of 12%, gasification temperature of 1500 K, pressure of 20 bar, and air-like gasification medium, the biomass gasifier’s flow rate is higher at higher syngas rates. The results verified that there is an optimum ER for each syngas rate, in which the slow growth of the ER revealed the maximum gasifier biomass flow rate. For ER growth at lower levels, the specific fuel consumption (SFC) of the RGT Unit declines sharply from the maximum value reached at 0.27 kg/kW·h at an ER of 5% to the minimum value reached at 0.80 kg/kW·h at an ER of 25% for the lowest gasification temperature of 1000 K. Moreover, ER growths at low levels have a significant effect on the RGT plant’s performance, leading to increased RGT thermal efficiency. The increase in the biomass moisture content led to a sharp decrease in the RGT thermal efficiency. The RGT thermal efficiency remains high at higher gasification pressure. The results revealed that the syngas lower heating value remains high at lower produced syngas rates. At the optimum ER, the H2 mole fraction depicted a value of 1.25%, 0.85% of CO, and 10.50% of CH4 for a lower heating value of 38 MJ/kg syngas. It is shown that the gasification air entered into the gasifier decreases amid the increase in the biomass moisture content. At different syngas rates (3–10 kg/s) and optimum ER, the results predicted that the Wood Chip biomass flow rates decrease when the gasifier efficiency increases. The simulation model revealed that ER growths at lower levels have a significant effect on increasing the power of the RGT plant.

Analysis of Gas-Turbine Type GT-009 M Low-Toxic Combustion Chamber with Impact Cooling of the Burner Pipe Based on Combustion of Preliminarily Prepared Depleted Air–Fuel Mixture

This article analyzes the mechanism of formation of the main components of harmful emissions characteristic of combustion chambers operating on conventional hydrocarbon fuels. The method of combustion of a preliminarily prepared depleted air–fuel mixture was chosen as the object of the study. This method of suppressing harmful emissions was implemented in the design of a low-toxic combustion chamber developed as applied to the GT-009 M type unit with impact cooling of the burner pipe and provides for stabilization of the main kinetic flame by means of a diffusion-kinetic and a standby burner device. The results of the calculations performed with regard to the operating conditions of the low-toxic combustion chamber at the nominal load of GT-009 M allow us to conclude that the practical use of combustion of a depleted, preprepared, fuel–air mixture in combination with diffusion-kinetic stabilization of combustion is promising. The topic of this article is related to the problem of ecological improvement of gas turbine unit combustion chambers, which determines its utmost importance and relevance.

Specific features of pressure pulsation control in combustion chambers of land based gas turbine units

LLC SPC Teplofizika, developing low-emission combustion chambers with premixing of fuel for ground application gas turbine installations, investigates the problems associated with the occurrence of pressure pulsations in the combustion chambers, as well as with the methods of their registration and measurement. To date, there is no unified method for assessing and calculating the amplitude-frequency characteristics of these pulsations and their measurement in general. This article is based on many years of experience in measuring and recording pressure pulsations under the conditions of a test bench and operation. Methods for evaluating and accumulating measurement results are presented, criteria for determining the average frequency and amplitude of oscillations are developed, reproducible in the course of experiments and during full-scale measurements. To detect vibrating combustion, an additional criterion of coherence of vibrations is also used with the aid of the entropy coefficient. As a result of the computational and experimental study, we find that the pulsation pressure in the volume of the combustion chamber does not allow the use of probes for measuring pressure pulsations in the air volume of the combustion chamber to reliably prevent the occurrence of vibrating combustion during its operation.

ИСПОЛЬЗОВАНИЕ ГАЗОТУРБИННЫХ ТЕХНОЛОГИЙ ДЛЯ ЭЛЕКТРОСНАБЖЕНИЯ ПРЕДПРИЯТИЙ НЕФТЕГАЗОВОГО КОМПЛЕКСА

The features of power supply for oil and gas enterprises, the design, features of the operation of gas turbine plants, methods of organizing a power supply system with elements of its own generation are considered, an autonomous power system with the organization of a direct cur-rent link has been developed to ensure stable operation of gas turbine units operating in paral-lel.

Multi-objective optimization of an integrated energy system against energy, supply-demand matching and exergo-environmental cost over the whole life-cycle

An integrated energy system (IES) can yield several benefits in energy, environmental impacts, cost, and flexibility over a separate system, although the initial cost may be higher. An IES using gas turbine, solar photovoltaics (PV), heat pumps, electrical cooling, and energy storage units is proposed here to satisfy the electricity, cooling, and heating demands of a residential building. A multi-objective optimization approach is used to find the best solutions considering energy, supply-demand matching and exergo-environmental economic indices with life cycle assessment (LCA) in following electric mode. The maximum benefit from the IES studied is reached with a system yielding 53.08% for energy savings, 99.88% matching, and 43.50% cost savings. The ideal scheme selected by the TOPSIS method has a higher annual total cost than the cost with conventional method, but has a better cost saving ratio, 41.81%. A sensitivity analysis shows that a higher PV use would decrease the fuel consumption, but it would reduce the matching and economic performance. Similar to the effect of natural gas price, the off-grid electricity price has higher impact on the cost saving ratio, but lower influence on the specific exergo-environmental cost.

Problems of acoustic safety in power engineering

Environmental safety issues are becoming increasingly important in the life of society. Among environmental safety issues in power engineering, acoustic safety occupies a special place. The problem of acoustic safety is associated with the fact that the regular operation of power equipment leads to an increased noise level, and power facilities are located in close proximity to residential areas. In this work, acoustic calculations were performed to determine the sanitary protection zone for gas turbines units (GTU) and combined cycle gas turbine units (CCGT) of various capacities. A formula was obtained for calculating the width of the sanitary protection zone depending on the capacity of gas turbine units and combined cycle plants and their number. It is shown that the sanitary protection zone (SPZ) of a power unit of high capacity is smaller than the sanitary protection zone of several power units of the same capacity. It is found that the noise levels from individual groups of equipment can determine the noise level at the entire border of the sanitary protection zone or in its individual sections. At the same time, noise suppression measures should be taken for all sources that generate noise levels in excess of standards. It is necessary to start noise suppression measures from those sources that generate excess noise in a larger section of the sanitary protection zone.

ИССЛЕДОВАНИЕ ВЛИЯНИЯ ВОДОРОДНОГО ТОПЛИВА НА ТЕРМОДИНАМИЧЕСКИЕ ПАРАМЕТРЫ АЛ-31СТ

The paper considers the possibility of switching the existing AL-31ST gas turbine unit from methane to hydrogen fuel. The calculation and comparison of the main thermodynamic parameters of a gas turbine installation on various types of fuel is carried out. The thermodynamic characteristics of the hydrogen plant are calculated while maintaining the gas temperature at the inlet to the high-pressure turbine. The use of hydrogen in the form of fuel will increase the efficiency of the installation, as well as reduce fuel consumption. Replacing methane with hydrogen allows you to get zero emissions of carbon-containing substances.

CHARACTERISTICS OF DIESEL AND GAS TURBINE POWER PLANTS FOR VEHICLES

Modern mobile vehicles, cars and tractors, include a diesel or gasoline piston engine, a manual or automatic gearbox, driving and driven axles with a differential mechanism. This kinematic scheme is time-tested and proved itself well. Diesel engines and low-speed generators working together represent a single power plant, a large-mass unit with low specific mass-to-power ratio. (Research purpose) The research purpose is developing a new kinematic scheme of a mobile vehicle with an electric drive for agricultural purposes with higher reliability, long service life and reduced weight and size characteristics of the power plant. (Materials and methods) Gas turbine agricultural machinery has never been produced in Russia, and the individual experimental studies conducted were not systemic. (Results and discussion) The mass-energy characteristics of gas turbine units are better than diesel ones, the vibration level is lower, the torque of the power plant is higher at low speeds, simpler tractor control, which opens up a wide prospect for their use on mobile agricultural vehicles. In the course of experimental studies on the processing of one hectare, they showed the advantage of a laboratory tractor with a gas turbine engine, relative to a tractor with a diesel engine, expressed, despite greater fuel consumption, in the use of cheap kerosene. (Conclusions) The developed kinematic scheme of the power unit and transmission allows to reduce the weight and size parameters, use cheaper fuel, improve the working conditions of the operator and increase the efficiency of technological operations.

Heat exchange crisis in mesh structures of power plant equipment

Thermal devices with porous structures, intended for the combustion chambers of gas turbine units, as well as for cutting and boring of the turbine housings of electric power plants have been developed and studied. Photographs of combustion chambers and nozzles, studied in terms of their geometry and thickening of the nozzle walls, excess oxidant (0.3-0.8) and the operating conditions until the limit state of the metal is reached (1 ? 106 W/m?) have been presented. The optimal geometry of the chambers and nozzles, as well as the type of porous structure have been determined. Coolant consumption has been reduced dozens of times, which has environmental significance. The appraisal of the structures studied showed the advantages to the flow cooling system. An analytical model of the heat exchange crisis is proposed. The system of differential equations for 1-D flow of one-phase liquid is solved. A physical picture of the heat exchange process is presented. In the equation of motion, the coefficient which determines the viscosity in the general pressure gradient is introduced. The actual velocity of the fluid is accounted for by the coefficient of moisture content in the porous structure.

Study heat exchange in porous structures

This paper shows the problem with heat exchange depending on units of thermal power plant equipment. The type of structures is determined and the heat flow for different pressures is proposed. Studies are developed for the condition of the heat exchange surface. Devices with porous coatings eliminate the development of cracks in the components and units of TPP equipment have been suggested. The research is applicable to gas turbine units of TPP. Comparable capillary-porous and flow systems have high reliability, but the former allowed the reduction of coolant consumption dozens up to 80 times. The results show that at higher heat loads it is suitable to use in porous surfaces to control the cooling surface. Evaluation of capillary-porous structures has shown their advantages over traditional cooling systems.

Selection of the Design of a Contact Condenser of a Gas-Steam Plant with Steam Injection into the Combustion Chamber

Due to the importance of the problems of implementing energy-saving technologies in modern conditions, one of the promising areas is the use of gas turbines for combined heat and power generation. One of the areas of effective development and technical re-equipment is the widespread use of highly economical combined steam and gas plants and gas turbines. The operation of the gas turbine unit “Aquarius” SE NPCG “Zorya-Mashproekt” with the injection of steam into the combustion chamber, which operates on the advanced cycle A-STIG and has in its circuit equipment for water regeneration, condensed from a vapor-gas mixture is considered. For condensation of steam from the vapor-gas mixture, a contact condenser-gas cooler is used, which is a mixing heat exchanger of complex design. The efficiency of heat transfer is determined by the design of the nozzle, namely, the developed heat transfer surface, small hydraulic supports, high heat transfer coefficients. An important aspect is the overall dimensions, which must be within certain limits. In the work it is offered to execute a design of the condenser in the form of a packed column. Different types of nozzles are considered to choose the best option. As a result of thermal design calculation of the contact capacitor, it is proposed to use Rashiga rings (15152) as a nozzle, which provide the lowest height of the nozzle at the required diameter of the device.

Investigation of the Influence of Gas Turbine Power Stations on the Quality of Electric Energy in the Associated Petroleum Gas Utilization

The problem of the quality of electric energy in the utilization of petroleum gas is considered. The article presents the results of the development of a mathematical description of power supply systems with gas turbine power stations based on two-shaft gas turbine units. The typical power distribution scheme of a gas turbine power station is given. The joint analysis of the generation modes of the gas turbine power station and the detected deviations of the power quality indicators values was carried out. The influence of the used mode on the power quality indicators is determined. As a result, the factors of operation of a gas turbine power station that affects power quality are identified, and recommendations for their elimination are given.

Development path of China's gas power industry under the background of low-carbon transformation

The natural gas power generation (hereinafter referred to as gas power) industry is an important force in the development process of clean energy in China, and it not only plays an important role, but also faces many challenges in the process of transformation to low-carbon energy. In order to explore the sustainable development path of China's gas power industry in the process of low-carbon transformation, this paper studies the carbon emission intensity of gas power unit in different scenarios by taking GE's three mainstream types of gas turbine units (6F.03, 9F.03 and 9HA.01) as examples, and then compares it with that of coal power unit in the same scenario based on industrial status and development trend. On this basis, the development path of gas power industry in the period of low-carbon transformation is proposed. And the following research results are obtained. First, the proposal of the time limit of carbon peak and carbon neutrality points out the goal and path of future low-carbon transformation in China. As a kind of low-carbon clean energy, natural gas will play a more important role in the process of energy transformation in China. Second, compared with coal-fired power generation, gas power is much more advantageous in emission reduction, so the orderly development of gas-based cogeneration has good direct emission reduction effects. Third, as a kind of flexible power source, gas power provides good guarantee and promotion for the development of renewable energy sources and the active development of gas-powered peak-shaving power stations has a good effect of collaborative emission reduction. Fourth, moderately increasing the proportion of natural gas and gas power in energy consumption before carbon neutrality can effectively exert their collaborative emission reduction effects and generate collaborative emission reduction benefits, so as to optimize energy resource allocation and maximize social welfare. In conclusion, gas power is one of the important ways to utilize natural gas.

Assessment of Organic Rankine Cycle Part-Load Performance as Gas Turbine Bottoming Cycle with Variable Area Nozzle Turbine Technology

Power cycles on offshore oil and gas installations are expected to operate more at varied load conditions, especially when rapid growth in renewable energies puts them in a load-following operation. Part-load efficiency enhancement is advantageous since heat to power cycles suffer poor efficiency at part loads. The overall purpose of this article is to improve part-load efficiency in offshore combined cycles. Here, the organic Rankine bottoming cycle with a control strategy based on variable geometry turbine technology is studied to boost part-load efficiency. The Variable Area Nozzle turbine is selected to control cycle mass flow rate and pressure ratio independently. The design and performance of the proposed working strategy are assessed by an in-house developed tool. With the suggested solution, the part-load organic Rankine cycle efficiency is kept close to design value outperforming the other control strategies with sliding pressure, partial admission turbine, and throttling valve control operation. The combined cycle efficiency showed a clear improvement compared to the other strategies, resulting in 2.5 kilotons of annual carbon dioxide emission reduction per gas turbine unit. Compactness, autonomous operation, and acceptable technology readiness level for variable area nozzle turbines facilitate their application in offshore oil and gas installations.

Refinement of arrangement of purifying elements of integrated air treatment device for gas transmission systems and power generation based on computational fluid dynamics

Gas pumping units with gas turbine units (GTU) are widely used in gas transmission systems. In recent decades, GTUs are increasingly used in power generation at thermal power plants. The efficiency and reliability of a gas turbine plant largely depend on the quality of air preparation. Integrated air cleaning devices (KVOU) as part of the air intake duct of the GTU have stages of coarse and fine air purification and rather large dimensions. The possibility of using a battery cyclonefilter with cleaning elements, in which both stages of cleaning are combined, in the design of the KVOU is considered. Numerical studies of the movement of a two-phase flow in a multicyclone, which is a model of the first 2 rows of a serial multicyclone, have been carried out. The first two rows of the serial multicyclone TsB-16 of the Biysk boiler plant, consisting of 16 cyclone elements 245 mm in diameter with a semi-coil gas supply, were taken as the initial geometric model. The geometric model was built using the Gambit preprocessor: a two-dimensional 2D model and a finite element mesh based on square elements were built. The finite element mesh of the numerical model generated in the Gambit program was exported to the solver of the ANSYS Fluent software package. Using the methods of computational hydrodynamics, the nature of the movement of a dusty flow in a battery cyclone with a corridor arrangement of cyclone elements has been investigated, their most effective placement has been determined, which provides the maximum inertial capture of suspended particles, in accordance with which a localization scheme for semi-coil entrances to treatment elements has been determined. In numerical studies, the aerodynamic characteristics of the dispersed flow in the multicyclone body are obtained. In accordance with the results of numerical studies, the efficiency of inertial sedimentation of suspended particles from the flow in the first row of elements was 36%, in the second row — 99%.

Analysis of Efficiency upon Enhancing the Fuel Combustion Completeness in the GTU Burners Using Fuel Gas Heating up

One main characteristic of the gas turbine unit (GTU) burner is its fuel combustion completeness, which affects directly the efficiency of the power plant along with CO and unburnt hydrocarbons CnHm emissions. The aim of this work was the research on the application of the fuel heating-up as an alternative method for increasing the fuel combustion completeness and controlling the emission of harmful agents. This goal is achieved by obtaining experimental data on the emissions of CO and NOx at different temperatures of the fuel gas supply to the combustion chamber. The most significant result of the work is the experimentally confirmed possibility of increasing the combustion efficiency (decreasing CO) by heating the fuel gas while maintaining constant gas-dynamic characteristics of the chamber. The significance of the results obtained consists in the experimental confirmation of the combustion quality control only by heating the fuel gas without changing the operating and design characteristics of the combustion chamber. The fuel combustion low completeness can cause the burner unstable operation in the form of the unsteady pre-blowout burning combined with the pressure oscillations in the burner. At present, methods for ensuring the increase in stability and completeness of the fuel combustion are related to the air rate and temperature changes at the inlet. However, the use of these methods can be unwanted because of their causing the decrease in the coefficient of efficiency and in the resource of the ‘hot part’ of the gas-turbine facility.

Dynamic performance simulation analysis method of split shaft gas turbine based on RBF neural network

In the operation of gas turbine unit, it often come across condition changes such as acceleration, deceleration and external drag effects. This will cause transient process of gas turbine system, which is of great significance to the dynamic performance simulation. This paper established dynamic simulation model of different components in gas turbine unit, introduced several process methods of compressor characteristic curves, and finally the RBF neural network method is used. Through simulation test, the variation rule of each parameter can be obtained so as to improve the operation efficiency of the whole unit, which lay a foundation for further optimization study.

Determination of the Design Characteristics of Heat Exchange Equipment for Heating Network Water of a Cogeneration Gas Turbine Unit with a Change in the Heat Load of Consumers in Regions with Different Climatic Conditions

Optimization studies of the dependence of fuel consumption on changes in the heat load of consumers in regions with different climatic conditions and taking into account the determination of the design characteristics of the equipment for heating network water of a cogeneration GTU were carried out. The GTU has two fuel combustion chambers, a waste-heat boiler and a contact heat exchanger for heating of feeding network water. Schematic-parametric optimization studies were carried out on the design mathematical model of the GTU. The analysis of the data of the circuit-parametric optimization made it possible to conclude that for the operating modes of the gas turbine plant with a higher thermal load, it is advantageous to slightly increase the heating surface area of the heater of feeding network water, the cost of materials for the manufacture of which is lower than for the waste heat boiler. This technical solution provided a relatively low increase in specific capital investments with full provision of consumers with electric and thermal energy. The data obtained in this work can be used to select the optimal technical solutions that ensure competitiveness in the operation of a cogeneration gas turbine unit in regions with different climatic characteristics.

Variable Modes of Operation of Combined-Cycle Gas-Turbine Units

Variable Modes of Operation of Combined-Cycle Gas-Turbine Units

Определение экономических показателей автономного энергокомплекса на базе ГТУ, ВЭУ и электрических аккумуляторов

In order to ensure high efficiency of natural gas use, increase the reliability and quality of energy supply, it is necessary to introduce alternative energy sources and electric accumulators into the classic GTU energy generation schemes. In this regard, the object of research is a combined autonomous source based on a gas turbine unit (GTU), a wind-driven power plant (WDPP) and energy storage. Energy production at wind turbines is conventionally divided into two stages (day and night), during the day energy is supply into the grid, and at night it is stored in energy storage. The purpose of the article is to determine the economic indicators of this variant of the scheme for combining sources of different types of generation. To determine the effectiveness of the source, a mathematical model was developed with the help of which quantitative and economic indicators are calculated. Initial data: daily schedule of electric loads, average monthly temperature and wind speed, dependence of changes in the electric power of WDPP on wind speed in relative units. According to the presented method, quantitative and economic indicators were calculated, which investigated the impact of changes in the installed capacity of WDPP (200 kW – 1400 kW) on changes in economic indicators: discounted costs, net present value, discounted profitability index (DPI), internal rate of return (IRR) and payback period. The annual output of electricity and heat is stable and amounts to 20409 MWh/year and 239970 GJ/year, respectively. In the publication, a comparative analysis of the obtained economic indicators was made. Discounted costs, despite the decrease in the installed capacity of the GTU, increase as the installed capacity of the wind turbine and energy storage increases. Economic efficiency is reduced, which is reflected in an increase in the payback period and a decrease in the NPV. The reason for this low efficiency is the high unit cost of wind turbines and energy storage. From the results obtained, it can be concluded that the lower the installed capacity of the wind turbine and, accordingly, the energy storage, the higher the economic indicators. At this time, the use of such combinations (GTU, WDPP and energy storage) is beneficial only if the share of the installed capacity of the wind turbine does not exceed 45% of the gas turbine capacity.