scholarly journals Application of a Two-Stage Steam Jet Injector Unit for Latent Heat Recovery of a Marine Steam Turbine Propulsion Plant

2021 ◽  
Vol 11 (12) ◽  
pp. 5511
Author(s):  
Szymon Grzesiak ◽  
Andrzej Adamkiewicz
Keyword(s):  
Steam Turbine ◽  
Steam Pressure ◽  
Relative Increase ◽  
Parameters Optimization ◽  
Feed Water ◽  
Water Heating ◽  
Two Stage ◽  
Heating Systems ◽  
Heating Steam ◽  
Numerical Research

The paper presents the results of the numerical research of the steam jet injector applications for the regenerative feed water heating systems of marine steam turbine propulsion plants. The analysis shows that the use of a single injector for a single heat exchanger results in a relative increase in the thermal efficiency of the plant by 0.6–0.9%. The analysis also indicates the legitimacy of the usage of multistage feed water heating systems, which would enable the operating parameters optimization of the injectors. The obtained steam pressure up to the value of 1.8 barA allows for the heating of the feed water up to 110 °C. For higher degrees of feed water heating in the heat exchangers, it is necessary to supply heating steam of higher pressure. Therefore, the usage of two-stage steam jet injector units was considered advisable for the analyses.

Aerodynamic Analysis of Steam Turbine Feed-Heating Steam Extractions

2014 ◽  
Vol 136 (11) ◽  
Author(s):  
Budimir Rosic ◽  
Cosimo Maria Mazzoni ◽  
Zoe Bignell
Keyword(s):  
Steam Turbine ◽  
Rotor Blade ◽  
Feed Water ◽  
Steam Turbines ◽  
Flow Angle ◽  
Steam Extraction ◽  
Heating Steam ◽  
Blade Row ◽  
Circumferential Distribution ◽  
Stator Blade

Feed-heating in steam turbines, the use of steam extracted from the turbine to heat the feed-water, is known to raise the plant efficiency and so is included in most steam turbine power plant designs. The steam is extracted through an extraction slot that runs around the casing downstream of a rotor blade row. The slot is connected to a plenum, which runs around the outside of the turbine annulus. Steam flows to the feed-heaters through a pipe connected usually to the bottom of the plenum. The steam extraction is driven by a circumferentially nonuniform pressure gradient in the plenum. This causes the mass flow rate of steam extracted to vary circumferentially, which affects the main passage flow downstream of the extraction point. The flow in the extraction plenum and the influence of the steam extraction on the mainstream aerodynamics is analyzed numerically in this paper. A complete annulus with the extraction slot and plenum together with the downstream stator and rotor blade rows is modeled in this study. The results reveal a highly nonuniform steam extraction around the annulus with the highest extraction rates from the bottom nearest the extraction pipe and the lowest at the top of the annulus. This difference in extraction rates modifies the flow angle and loss circumferential distribution downstream of the stator blade row. This study finds out that the distribution of steam extraction around the annulus and its influence on the main passage flow could be greatly improved by changing the shape and increasing the volume of the extraction slot and plenum.

A Parametric Study Method of Enhancing the Efficiency of Gas Turbine Combined Cycle Power Plant

2013 ◽  
Author(s):  
Jingjin Ji ◽  
Bo Sun ◽  
Dequan Zuo ◽  
Lei He
Keyword(s):  
Power Plant ◽  
Steam Turbine ◽  
Gas Turbine ◽  
State Of The Art ◽  
Structure Design ◽  
Combined Cycle ◽  
Parameters Optimization ◽  
Cycle Performance ◽  
Feed Water ◽  
Combined Cycle Power Plant

At the present time, with the ever-increasing energy price, gas steam combined-cycle power plant is well received and favored by Chinese local investors due to its quickly-start and stop, high operational flexibility, high thermal efficiency, clean exhaust flue gas, short construction period characteristics. Recent researches make many efforts on the optimization of gas turbine intake system, main equipment parameters matching, and cold side of steam turbine to increase the overall performance of combined cycle. In the paper, we focused on a kind of triple-pressure reheat combined cycle equipped with a state of the art gas turbine, which is gradually entering Chinese market. An accurate overall combined cycle model was built up for the purpose of increasing the efficiency by means of steam parameters optimization. The influence of steam pressures and temperatures of each sections, feed-water regenerative heating and fuel preheating on combined cycle performance are evaluated with the model, the restriction factors such as temperature difference of heat recovery steam generator (HRSG) and steam turbine structure design were also considered. A set of optimum parameters are obtained for combined cycle equipped with a state of the art gas turbine by using the proposed method on enhancing combined cycle performance equipped with a certain type of gas turbine.

scholarly journals Innovative design of exhaust enthalpy algorithm for small turbine

2021 ◽  
Vol 2083 (3) ◽  
pp. 032020
Author(s):  
Lingkai Zhu ◽  
Qian Wang ◽  
Song Gao ◽  
Ziwei Zhong ◽  
Panfeng Shang ◽  
...  
Keyword(s):  
Steam Turbine ◽  
Steam Pressure ◽  
Feed Water ◽  
Water Pump ◽  
Comprehensive Understanding ◽  
Safe Operation ◽  
Innovative Design ◽  
Pump Inlet ◽  
Reliable Basis ◽  
Small Measurement Error

Abstract This paper presents a method to determine the exhaust enthalpy of small steam turbine. Starting from the feed water pump group, the feed water pump and small steam turbine are studied as a whole. Based on the thermodynamic method, the efficiency of the feed water pump is obtained separately, and then the efficiency and exhaust enthalpy of the small steam turbine are deduced. This method only needs to measure the inlet and outlet pressure, temperature, feed water flow of feed water pump, inlet steam pressure, temperature and flow of small turbine. It has the advantages of less measurement parameters, low measurement cost and small measurement error. It provides a reliable basis for a comprehensive understanding of the performance of small steam turbine and guiding its economic and safe operation.

Efficiency of two-stage heating of water on CHP plant with turbines of type T-250/300-240

2019 ◽  
Vol 12 (3) ◽  
pp. 213-219
Author(s):  
E. T. Ilin ◽  
S. P. Pechenkin ◽  
A. V. Svetushkov ◽  
J. A. Kozlova
Keyword(s):  
Transition Period ◽  
Steam Pressure ◽  
Low Pressure ◽  
Heat Extraction ◽  
Two Stage ◽  
Permissible Level ◽  
Lower Heat ◽  
Operational Modes ◽  
Extraction Section ◽  
Supply Water

During non-heating and transition period, most of cogeneration turbines operate with a lower heat extraction section actuated only due to a number of restrictions on the maximum and minimum pressure levels in the upper and lower heat extraction sections at operation of the turbine. For turbines of model T-250/300-240, the minimum permissible level of steam pressure in the upper heat extraction section, according to manufacturer data, is set to 0.06 MPa. During the non-heating and transition period, the supply water temperature is usually set in the range of 70–75°С. In order to maintain that temperature of supply water, the steam pressure in the upper heat extraction section should be below the minimum permissible level. As a result, the turbine operates with only the low-pressure heat extraction section actuated, which ensures operation without restrictions, but with a lower efficiency. The authors have introduced a set of measures, which enable to avoid those restrictions and implement two-stage heating of supply water. In this case, on connection of the upper heating extraction section, the pressure in the same is maintained at the minimum permissible level. Heat output characteristics are provided by having some of supply water delivered bypassing the group of network heaters. This operational mode enables to increase the turbine actual heat drop, to reduce the cooling steam flow into the low-pressure section and, accordingly, into the condenser, and to reduce temperature drops in network water heaters. Results of the research of operational modes for turbines of type T-250/300-240 in the non-heating and transition period with one and two-stage heating are provided. The economic efficiency of proposed operational modes was researched, which shows the effectiveness of those modes during non-heating and transition period. The limits of the efficiency of using these modes are determined.

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