Evaluating Small vs. Large Power Blocks for Pipeline Compression Stations

This paper discusses how the application of large, gas turbine-based power blocks (>50,000-hp) in pipeline compression stations can contribute to lower capital costs, improved lifecycle performance, and reduced carbon emissions. For illustrative purposes, two compression facility power block configurations (nine 30,0000-hp trains vs. five 55,000-hp trains) are compared on the basis of capital expenditures (CapEx), operating expenditures (OpEx), availability, efficiency, and operating flexibility. A summary of the study's results are as follows: – Net present value (NPV) analyses show that 5x55,000-hp ISO trains can result in up to $50 million reduction in CAPEX vs 9x30,000-hp ISO trains – By having fewer trains, operations & maintenance (O&M) costs can be reduced by as much as 20% – Lifetime fuel savings with a 5x55,000-hp train configuration vs. 9x30,000-hp trains are estimated at $40 million, owing to the increased operating flexibility of modern gas turbines, even at partial loads. The paper will also present considerations for digitalization, modular construction, and package integration – with a particular focus on how these measures can be leveraged to lower execution risk and enhance the lifecycle performance of gas turbine-driven compression trains.

OPERATION OF ELECTRIC HEAT-GENERATION GAS TURBINE PLANTS OF COMPLEX CYCLES ON NOMINAL AND VARIABLE MODES

The results of research and development of cogeneration gas turbine engines (GTE) of complex cycles are presented. It is shown that the use of an overexpansion turbine (OT) in a gas turbine engine makes it possible to increase the efficiency of the engine on a par with the use of heat regeneration (R). The combination of these two methods in a GTE with OT and R provides a further increase in the engine's efficiency. It has been established that at partial loads, each design scheme has its own patterns of change in engine characteristics, which determine the field of application of cogeneration gas turbine engines. Examples of the possibilities of changing the working process in the engine are given, which allow to control the energy flows in the cogeneration power plant.

Assessment of downward draught in high-glazing facades in cold climates – experimental and CFD study into draught control with a 21-type radiator

This paper investigates the interaction of a radiator’s thermal plume and downdraught of cold glazed surfaces. Draughts in working areas are one of the most common thermal comfort complaints in modern buildings. A typical solution for dealing with these draughts is positioning the heat emitters such as radiators or convectors under the windows. However, with thermally efficient envelopes, the internal loads compromise a relatively high fraction of the heating demand and the emitters are working under partial loads in modern buildings. This study comprises two parts: an experimental phase in the EN442 standardized test chamber with a 21-type radiator, and a CFD simulation phase, where the model is validated and applied under an expanded set of boundary conditions. The expanded simulation set results provide preliminary insight into sizing and design. More specifically, the thermal plume can be parametrised with a velocity and temperature value along with the room air and glazing temperatures for a broader analysis and assessment of the risk of draught.

Determination of the Idle Mode of the Stage of Axial Turbine during Operation at Partial Loads

On the basis of the one-dimensional theory of calculating the operation of steam turbine stages the method for determining the idle mode, the initial data for which are the geometric characteristics of the blade rows is proposed. Formulas have been obtained that make it possible to calculate the efficiency in the proximity of Rotor Blades (RB) at operating modes from nominal to the idle mode, depending on the flow rate of the stage and taking into account the use of kinetic energy with the runaway velocity and losses arising at off-design angles of flow on the Rotor Blade (RB). The results of possible computational studies and their comparison for an incompressible working fluid with the results of experimental studies showed the good possibilities of the proposed method for determining the idle mode in a wide range of the characteristics of stages.

Variable operating modes of the closed gas turbine plants for propulsive complexes in the underwater technics

Выполнение в условиях Арктики транспортных операций с преодолением ледовых полей, а также разведки, обустройства и эксплуатации подводных добывающих комплексов существенную роль будут играть суда и аппараты, оснащенные замкнутыми газотурбинными установками (ЗГТУ) различных схем в составе пропульсивных комплексов. В работе проведен анализ ЗГТУ, часто работающих на частичных нагрузках в составе пропульсивных комплексов подводной техники. В качестве исходных данных представлены характеристики на номинальных режимах работы ЗГТУ с регенерацией теплоты (Р) и ЗГТУ с турбокомпрессорным утилизатором (ТКУ) и Р как наиболее перспективных для подводной техники. Одноконтурные ЗГТУ, работающие на углеводородном топливе с окислителем воздухом, в качестве рабочего тела используют смесь азота и продуктов сгорания топлива. Установлено, что как на номинальных, так и на частичных нагрузках экономичность ЗГТУ с ТКУ и Р выше, чем ЗГТУ с Р. ЗГТУ на частичных винтовых нагрузках более экономичны, чем на генераторных. ЗГТУ могут одновременно производить тепловую и электрическую энергию, обеспечивая высокую энергоэффективность установки в условиях эксплуатации. Performance in the conditions of the Arctic of transport operations with overcoming ice fields, and also investigations, arrangement and operation of the underwater extracting complexes an essential role will be played by the vessels and apparatus equipped with the closed gas turbine plants (CGTP) of different schemes as a part of propulsive complexes. In work the analysis of CGTP which are often working at partial loads as a part of propulsive complexes of the underwater technics is carried out. As basic data characteristics are presented on rated operating modes of CGTP with regeneration of warmth (R) and CGTP with the turbocompressor utilizer (TCU) and R as the most perspective for the underwater technics. Single-circuit CGTP, using hydrocarbon fuel with an oxidizer air, as a working body – the mix of nitrogen and products of fuel combustion. It is established that both on rated, and on partial loads profitability of CGTP with TCU and R is higher, than CGTP with R. CGTP on partial screw loads, are more economic than on generating. CGTP can product at the same time heat and electrical energy, providing high energy efficiency of plant under operating conditions.

АНАЛІЗ ЕФЕКТИВНОСТІ ОХОЛОДЖЕННЯ ПОВІТРЯ НА ВХОДІ КОГЕНЕРАЦІЙНОГО ГАЗОПОРШНЕВОГО МОДУЛЯ НА ЧАСТКОВИХ НАВАНТАЖЕННЯХ

The fuel efficiency of the reciprocating gas engine deteriorates with the increase of ambient air temperatures at the inlet to the radiator of the recirculating cooling water system for cooling the scavenge gas/air mixture at the inlet of the working cylinders and the air at the inlet of the scavenge air turbocharger. The peculiarity of cogeneration reciprocating gas modules of plants for combined production of electricity, heat, and cold is the operation mainly at partial loads according to the schedules of consumption of electricity, heat, and cold. The efficiency of cooling air of cogeneration gas module on the partial loads was analyzed on the example of an integrated power supply installation, which includes two cogeneration reciprocating gas engines JMS 420 GS-N.LC GE Jenbacher, manufactured as the cogeneration modules with exchangers using the heat of exhaust gases, scavenge gas-air mixture, cooling water of the engine shirt and lubricating oil for heating water. Hot water heat is transformed by the AR-D500L2 Century absorption lithium-bromide chiller into a cold that is spent on technological needs and for the operation of a central air conditioner that cools the engine room income air from where it is sucked by a scavenge air turbocharger. Because of significant heat influx from working engines and other equipment, as well as through the enclosures of the engine room from the outside to the air-cooled in the central air conditioner in the engine room, from where it is sucked by a turbocharger, the air temperature at the inlet of the turbocharger is quite high: 25...30 °C. At elevated temperatures of the ambient air at the inlet of the radiator for cooling scavenge gas-air mixture and the air at the turbocharger inlet the fuel economy of engine is falling, which indicates the need for efficient cooling of air. The efficiency of cooling the air of the reciprocating gas module was estimated by a reduction in the consumption of gas fuel and an increase in electric power of the engine. For this purpose, the data of monitoring on the fuel efficiency of the reciprocating gas engine with the combined influence of the ambient air temperature at the inlet of the radiator and the air at the turbocharger inlet were processed to obtain data on their separate effects and to determine the ways to further improve the air cooling system of the reciprocating gas module.