Turbine Exhaust Research Articles

Chaotic Analysis of the Reversible Pump Turbine Exhaust Process in Pump Mode Based on a Data-driven Method

Due to the important strategic position of Pumped Storage Power Plants (PSPP) in global energy upgrading, conducting in-depth research on the various operating conditions of pump turbine units is important for their safe and stable operation. This study sought to clarify the gas–liquid phase motion and the nonlinear chaotic characteristics of the process of exhaust and pressurization in pump mode; with the simplified objective model proposed here, a visualization of the process is achieved using data-driven methods, and the nonlinear characteristics of gas–liquid phase motion during the process are theoretically demonstrated. A method that combines data-driven and chaotic analysis is proposed to qualitatively and quantitatively analyze the force and torque time-series signals of the runner under different exhaust rates. The results indicate that the chaotic characteristics of the force signals and torque signals of the runner are not in a single linear relationship with the exhaust rates. Therefore, this research also provides guidance on exhaust rates with the aim of informing actual engineering practice, the purpose of which is to reduce the vibration amplitude caused by repetitive torque and improve the stability of the unit operations.

Thermodynamic evaluation of a Ca-Cu looping post-combustion CO2 capture system integrated with thermochemical recuperation based on steam methane reforming

The calcium looping integrated with the chemical looping combustion (CaL-CLC) process is an efficient and cost-effective CO2 capture technology that avoids the energy-intensive air separation unit in the calcium looping (CaL) process. However, in these CaL-CLC and CaL system integration schemes, the carbonation heat is utilized for steam generation, resulting a significant temperature difference and considerable irreversible loss. To prevent temperature mismatch, this paper proposes a novel Ca-Cu looping post-combustion CO2 capture method with thermochemical recuperation based on steam methane reforming. Additionally, a novel system integrated with turbine exhaust heat recovery is introduced to effectively reduce carbon emissions from flue gas. Results show that the proposed system has superior performance compared to the reference system based on the Ca-Cu looping method. The specific primary energy consumption for CO2 avoidance decreased from 2.40 MJLHV/kg CO2 in the reference system to 2.02 MJLHV/kg CO2. Exergy analysis indicates that a total of 3.0 % reduction in exergy destruction can be achieved in chemical reaction processes and heat recovery processes, contributing to the superior performance of the proposed system. Furthermore, the effects of key operating parameters indicate that cascaded turbine exhaust recovery is essential for improving the thermodynamic efficiency of the proposed system. Overall, recovering the mid-temperature carbonation heat via thermochemical regeneration and integrating with exhaust heat recovery contribute to reducing SPECCA, thus providing a promising low-energy-consumption alternative for CO2 capture.

Performance of sCO2 Cycles for Waste Heat Recovery and Techno-Economic Perspective As Gas Turbine Bottoming Cycle

Abstract Supercritical carbon dioxide (sCO2) cycles are compact and widely adaptable to various heat sources, including the waste heat from gas turbine (GT) exhaust gases. While the addition of a steam cycle enhances the typical 40%-efficiency of GTs up to 60%, their substantial investments render them less appealing for smaller GTs. This creates an opportunity for sCO2 cycles, but a comprehensive comparison of their performance with that of steam across a range of applications remains lacking. Moreover, their applicability to various industrial scenarios based on existing installations is missing from a techno-economic standpoint. To address these needs, four promising sCO2 cycles are optimized and compared with the simple steam cycle. Their techno-economic performances are then investigated for 20 industrial GTs of different size. The analysis yielded performance maps demonstrating comparable performances for sCO2 and steam cycles, as well as significant techno-economic advantages for sCO2 bottoming cycles for smaller GTs. However, when it comes to larger GTs combined with reheats and expansions steam cycles, sCO2 cannot outperform them in current technological standards. Nevertheless sCO2 cycles offers an attractive alternative, facilitating cogeneration. Among the different approaches designed to integrate the heat requirements of amine-based capture, steam cycles have always proved more suitable because of the thermal stability of amines. In conclusion, the research underscores the cost-effectiveness and adaptability of sCO2 cycles for heat recovery applications, particularly as bottoming cycles for smaller GTs, while larger GTs present a challenge.

Economic Analyses of a New Power and Cooling System at Low Temperature Applications

Recent research suggests that the implementation of more efficient combined cooling and power systems, which enable the cogeneration of electricity and cooling, can enhance the efficiency of hybrid plants. The present investigation is motivated by finding that, in the literature review on combined power and cooling systems, there is very limited information on the coupling of the organic Rankine cycle (ORC) and the ejector refrigeration cycle (ERC) with low sink temperatures. A suggested approach to do this involves using hot exhaust gas and waste heat engines to power an ORC hybrid system. To enhance the ORC–ERC system's performance, three heater configurations use waste heat from the ORC turbine exhaust, ejector, and engine waste heat to heat the working fluid. Renewable energy sources are the primary focus of most current research initiatives. The present research focuses on unique ORC and ERC systems, considered as combined power and cooling systems, with the goal of improving exergy performance at low temperatures. The suggested ORC–ERC can generate energy destruction of 69.85 kW at a source temperature of 155 °C, with an exergetic efficiency of 76.9% at the turbine. Setting the entrainment ratio at 0.5 results in a total sum unit cost of products (SUCP) of 465 $/kW‐h for the ORC–ERC. Furthermore, the 37.83% exergy destruction ratio introduces heat exchanger 2 (HE2) as the primary cause of the suggested ORC–ERC's irreversibility. A detailed parametric study reveals that altering the hot source temperature and entrainment ratio improves the system's SUCP. The current examination at high sink temperatures may be expanded to an advanced exergoenvironmental investigation.

Investigation of Gas-Turbine Afterburner with Aluminized Fuel-Rich Propellant

This paper describes the design and development of a compact afterburner system for a mini gas turbine engine using aluminized fuel-rich propellant. The working principle of the system is analogous to a dual combustor ramjet engine in which the propellant is burnt in the primary chamber. Hot gases from the primary chamber combust further in the secondary chamber with incoming air from the inlet. In this work, fuel-rich gases were injected into the afterburner through radially mounted gas generators. The hot gases mix with the oxygen-rich turbine exhaust and burn further, resulting in high-enthalpy gases. These high-enthalpy gases were expanded in the convergent nozzle to generate higher exit velocity. This study investigated the thrust enhancement capability of the gas turbine afterburner system with fuel-rich propellant grains at different operating conditions. Furthermore, the effect of increasing afterburner length and decreasing nozzle exit diameter on the performance of the system was also examined. An overall static thrust of about 320 and 360 N was obtained for three and four grains, respectively, with maximum unburnt fuel residues of 11% in both the cases, out of which four grain configurations achieved a maximum thrust enhancement of around 180%.

Numerical study of film cooling at the outlet of gas turbine exhaust

Abstract In order to mitigate the potential operational damage risk caused by traditional cooling methods in engineering applications of heavy-duty gas turbine component testing, the film cooling unit and realizable K-epsilon turbulence model were employed. Numerical simulations were conducted for multiple exhaust film holes with varying curvature and pitch-row under different operating conditions. The heat transfer distribution along the flow direction and radial direction of the high temperature wall was analyzed, as well as the influence of heat transfer under different geometrical parameters. The results indicate that for the integrated configuration of large-diameter cooling units, a blowing ratio of 0.3 yields the most comprehensive cooling effect, primarily due to the extensive spatial coverage by the gas film and the weakening of eddy dissipation mechanisms. Additionally, it was observed that with an increase in hole distance ratio for multiple exhaust film holes, cold air could more stably participate in heat exchange with high-temperature flue gas wake at the outlet of the gas film hole; thus, a hole distance ratio of 3.0 provides optimal comprehensive cooling effects.

Studi Numerik Pengaruh Sudut Bukaan Damper dan Flue Gas Temperatur Terhadap Distribusi Temperatur Pada Heat Recovery Steam Generator (HRSG)

The Combined Cycle Gas Turbine Power Plant (PLTGU) utilizes the waste heat from the gas turbine to produce steam in a Heat Recovery Steam Generator (HRSG). The steam from the HRSG is then used to generate electricity in a steam turbine. In HRSG operation, several variables significantly impact its performance, including the damper angle and inlet temperature. At the Tanjung Uncang Power Plant in Batam, the manufacturer's standard operating procedure (SOP) requires that the exhaust gas temperature when the damper is open must be below 400°C. However, the gas turbine with an initial load of 5 MW has an exhaust gas temperature of 560°C - 580°C. Therefore, it is necessary to perform a gas turbine load release or FSNL (Full Speed No Load) to reduce the inlet temperature of the gas turbine. During FSNL, there are SOPs for diverter damper angles of 51°, 68°, and 90°. This leads to the need for analyzing the impact of diverter damper angles and inlet temperature on the flow pattern and temperature distribution. The analysis was conducted using CFD (Computational Fluid Dynamics) with ANSYS Fluent 2020 software. The variations used are diverter damper angles of 51°, 68°, and 90°, combined with inlet temperatures of 400°C and 580°C. The simulation outputs include velocity contours, temperature contours, and equivalent stress on the superheater tubes. The HRSG simulation results show that the flue gas is not distributed uniformly. The turbine exhaust gas only spreads along 4 – 11 meters, leading to slower steam production from the superheater. Additionally, when the superheater tubes are empty, the steady-state thermal and structural simulation results indicate that an inlet temperature of 580°C, whether at damper angles of 51°, 68°, or 90°, can cause a larger temperature difference between the inner and outer walls, ranging from 117.04°C to 125.5°C. This temperature difference can lead to thermal stress on the superheater tubes. This is shown in the S-N Curve for SA 213 T22 material, with a convection coefficient of 5 W/m² K (no steam), where the equivalent stress exceeds the endurance limit (infinite zone).

Studi Numerik Pengaruh Penambahan Turning Vane Terhadap Bentuk Aliran dan Distribusi Temperatur di Heat Recovery Steam Genertor (HRSG)

Tanjung Uncang Power Plant is one of the facilities in Indonesia that utilizes CCGT (Combined Cycle Gas Turbine). This cycle uses an HRSG (Heat Recovery Steam Generator) to heat steam using the exhaust gases from the gas turbine. At Tanjung Uncang's HRSG, the SOP requires that the gas turbine exhaust during cold start conditions must be below 400°C. Meanwhile, the gas turbine at Tanjung Uncang has a base load of 5 MW with a temperature range of 560°C - 580°C. Therefore, an asynchronous process is necessary to reach the FSNL (Full Speed No Load) condition for the gas turbine, with the damper angles set at 51°, 68°, and 90° for 45 minutes. Additionally, to achieve optimal conditions with the gas turbine running at 45 MW, a time span of 8 hours is required, which results in losses of up to 700 million. The extended time required can be due to uneven flue gas distribution, necessitating time for the HRSG to reach optimal conditions. This underscores the need to analyze the effects of adding turning vanes with angles of 35°, 53°, and 71°, and inlet temperatures of 400°C and 580°C on the characteristics of flue gas distribution. The analysis was conducted using CFD with ANSYS Fluent 2021 software. The simulation outputs include velocity vectors, velocity contours, and temperature distribution contours.

Cryogenic carbon capture design through [formula omitted] anti-sublimation for a gas turbine exhaust: Environmental, economic, energy, and exergy analysis

To achieve a net zero-emission society, current industries must transition to become less carbon-intensive while fulfilling the rising power demand. In this study, we present a novel multigeneration system that produces power, cooling, and solid carbon dioxide by applying cryogenic carbon capture to a gas turbine flue gas. The energy recovery concept is efficiently employed to avoid energy and exergy losses in the system. The system is simulated in Aspen Plus with the mathematical models of the exergy streams and solid-vapor equilibrium written in Matlab. The performance of the plant is assessed based on energy, exergy, economic, and environmental evaluations. Thermodynamic analysis indicates that 1.2 MJ of electricity is required to capture 1 kg of CO2 from the gas turbine exhaust gas (which is lower compared to conventional systems) with 100 % CO2 purity. The net generated power, energy efficiency, exergy efficiency, m˙CO2,captured, and m˙CO2,emitted for the proposed system are 179.4 MW, 41.2 %, 59.3 %, 500,000 tons annually, and 255,000 tons a year, respectively. Sensitivity analysis shows that reducing the flue gas temperature positively impacts the CO2 content in the flue gas while having a negative effect on energy and exergy efficiency. The economic investigation shows that the system is economically profitable.

Economic and operational assessment of solar-assisted hybrid carbon capture system for combined cycle power plants

The paper presents a post-combustion CO2 capture process which involves two configurations for enhancing the CO2 separation driving force in the conventional amine-based Carbon Capture System (CCS): a multi-stage membrane module for selective exhaust gas recirculation (SEGR case) and the combination of turbine exhaust gas recirculation with SEGR (EGR + SEGR case). Furthermore, the stripper reboiler in both configurations is integrated with a parabolic trough solar collector field with a 4-h thermal energy storage to provide the required thermal duty for solvent regeneration. Various system components are designed, simulated, and integrated with an economic model to evaluate the system's techno-economic performance across a wide range of loads. The results show that the proposed designs have efficient part-load performance although efficiency degradation is inevitable during partial-loads. A stable supply of solar thermal energy results during the partial operation of NGCC even during night. The EGR + SEGR case represents the case with the lowest levelized cost of electricity and CO2 avoided cost, 81.43 $/MWh and 101.66 $/tonneCO2, among the CCS-equipped designs, which highlight the advantages of this design over baseline and SEGR case. The proposed hybrid system shows promise for significantly decarbonizing fossil-fuel power plants and increasing power sector flexibility.

A novel biogas-driven CCHP system based on chemical reinjection

In the process of vaporizing water within the biogas-driven CCHP system based on chemical recuperation, a significant temperature disparity in heat transfer exists, leading to increased irreversible loss, and the methane conversion rate is low because the gas turbine exhaust gas is difficult to drive efficient methane conversion. This paper proposed a novel biogas-driven CCHP system based on chemical reinjection. Through the reinjection of a portion of the exhaust gas into the reactor, a self-thermal reforming reaction process is engineered, leading to a substantial enhancement in methane conversion rate. The heat matching of the heat exchange unit is optimized by the reheat air, and the power generation and cooling capacity of the system are improved. Notably, the electricity and cooling generation of the new system increased by 55.52 kW (6.20 %) and 542.49 kW (101.49 %), respectively, while the exergy efficiency increased by 8.31 %. The study delves into the influence of key parameters on the system thermal performance. During the reforming process, the exhaust gas split ratio has a significant impact on carbon deposition and methane conversion. When the methane is nearly completely converted, there is no significant change in electricity generation of the system. Excessive turbine inlet temperature is found to be unfavorable for improving the exergy efficiency of the new system from a holistic system perspective. Finally, a comprehensive comparison of the thermal performance between the new system and the reference system is conducted under various ambient temperatures. This study offer a new design scheme for the efficient utilization of biogas.

Aerodynamic noise and its reduction of the marine gas turbine air exhaust system.

The aerodynamic noise of pipelines is an important part of the noise of a ship's system. This paper conducted numerical investigations on the flow and acoustic characteristics of the marine gas turbine exhaust system. The near-field and far-field acoustic characteristics of the internal flow noise of the exhaust system are calculated by employing the Möhring's sound analogy method. In addition, the far-field acoustic characteristics of the external jet flow noise of the exhaust system are calculated by employing the stochastic noise generation and radiation (SNGR) method. Two kinds of protrusions are added to the main nozzle outlet to achieve noise reduction. The internal sound field of the marine exhaust system is dominated by low frequency sound sources, which are more obvious as the exhaust mass flow rate decreases. As for the external sound field of the marine exhaust system, the peak frequency of the far-field noise spectrum decreases with the decrease in the exhaust mass flow rate. The eight periodic protrusions perform better in reducing the internal aerodynamic noise of the exhaust system, while the five aperiodic protrusions perform better in reducing the external jet noise of the exhaust system.

Energy, exergy and economic analysis of a poly-generation system combining sludge pyrolysis and medical waste plasma gasification

To optimize the processes of treating medical waste and pyrolyzing sludge, we propose a new integrated system that combines plasma gasification for medical waste treatment, combined cycle power generation, and sludge pyrolysis. The medical waste is first incinerated, and then the synthesis gas from plasma gasification powers a gas turbine to generate electricity in this integrated system. The gas turbine's exhaust gas heats steam and feedwater from the HRSG to achieve a combined gas-steam cycle. Simultaneously, turbine exhaust steam energizes sludge pyrolysis, allowing for efficient conversion of medical waste into electricity in an eco-friendly manner. A hybrid design study was conducted using different methods, including energy, exergy, and economic analysis. The study revealed that the medical waste-to-energy system integration has the potential to attain 66.31% energy efficiency and 66.70% exergy efficiency. Moreover, the medical waste-electricity project has a dynamic payback period of 2.46 years and a relative net present value of 38,949.91k$. These outcomes suggest that this innovative concept is practical, advantageous, and has excellent potential for further development in the field of waste-to-energy conversion.

Predicting the Performance of Turbine Exhaust Diffuser-Collector Systems Across the Operating Range: Comparison of Lattice-Boltzmann Method Simulations With Experiments

Abstract The predictive capability of the lattice-Boltzmann very large eddy simulation (LBM-VLES) methodology was evaluated for industrial gas turbine exhaust diffuser-collector applications. The effort focused on evaluating the accuracy of performance predictions against experimental rig data gathered at engine representative conditions including the Reynolds number, Mach number, and inlet flow conditions. The performance prediction capability of LBM-VLES simulations was also compared against Reynolds-averaged Navier–Stokes (RANS) simulations. Evaluations were completed for two distinct exhaust rig geometries at conditions indicative of their respective design points, and the performance prediction capability was also evaluated at conditions depicting two off-design cases. The off-design conditions were represented by an increase in inlet swirl angle and associated incidence on the diffuser struts. Overall, the authors found that LBM-VLES simulations were a suitable approach for predicting the performance of gas turbine exhaust diffuser-collector systems at both on- and off-design conditions. The LBM-VLES simulation accuracy was substantially better than that achieved by RANS simulations, with 66% lower RMS pressure recovery error between computational fluid dynamics (CFD) and experiments for the four cases studied, and an 89% reduction in error for the furthest off-design case. The computational cost of the transient LBM-VLES simulations was roughly the same as the RANS simulations performed using best practices for that solver.

ANALYSIS OF THE CORRECTNESS APPROACHES TO DETERMINING THE SPECIFIC IMPULSE OF THRUST GENERATED BY THE WORKING FLUID OF A GAS GENERATOR CYCLE ROCKET ENGINE TURBINE

For liquid rocket engines (LREs) utilizing the gas generator cycle, the resulting engine thrust is composed of two components: the thrust of the engine chamber and the thrust of the turbine exhaust nozzle. Over the years of LRE utilization, methodologies for calculating ideal thermo gas dynamic parameters of the chamber have been developed, large volumes of statistical data regarding specific impulse losses in engine chambers have been obtained, and approaches for predicting specific impulse and, consequently, thrust of the main chambers have been refined. A much more complex situation arises with determining the specific impulse of the thrust generated by the working fluid of an autonomous turbine: significant limitations in information regarding methods for calculating this parameter have been found during literature analysis, and the available statistics exhibit contradictory characteristics. Accurate prediction of the specific impulse of the thrust from turbine exhaust nozzles allows for a more rational selection of design parameters (e.g., combustion chamber pressure) during the development of a new engine and is particularly important in cases where the spent gas generator gas is used to create control efforts. As the rocket and space industry historically developed under conditions of increased secrecy, many approaches and design methods for LREs remain known only to design bureaus and research institutes that were founded and developed during the heyday of rocket and space technology. This complicates the situation for new, young aerospace companies, as they must either conduct physical tests, which require expensive specific test equipment and increase the time and cost of engine development, or use numerical modeling, which, although to some extent allows for the replacement of physical experimentation, requires model verification and confirmation of the assumptions made. Furthermore, considering the military focus of rocket-related topics in the past, it cannot be excluded that intentionally distorted information may be present in open sources. Thus, considering the global trend of increasing the number of startups in the rocket and space industry, the identification of reliable and open sources of information becomes an important task. In this work, data from open sources regarding the specific impulse of the thrust from turbine exhaust nozzles of existing LREs were analyzed, revealing significant inconsistencies in the declared energy parameters. Numerical modeling of generator gas leakage from the nozzle of the exhaust gas duct of the RD-111 engine turbine has been conducted, and the results were compared with the calculations carried out by other methods. As a result of the work, various approaches to evaluating the thrust of exhaust nozzles during the design of an engine utilizing the gas generator cycle were analyzed, and conclusions were drawn regarding the correctness of their application.

A general class of improved population variance estimators under non-sampling errors using calibrated weights in stratified sampling.

This paper proposes a new calibration estimator for population variance within a stratified two-phase sampling design. It takes into account random non-response and measurement errors, specifically applying this method to estimate the variance in Gas turbine exhaust pressure data. The study integrates additional information from two highly positively correlated auxiliary variables to develop a general class of estimators tailored for the stratified two-phase sampling scheme. The properties of these estimators, in terms of their biases and mean square errors, have been thoroughly examined and extensively analyzed through numerical and simulation studies. Furthermore, the calibrated weights of the strata are derived. The proposed estimators outperform the natural estimator of population variance. Finally, suitable recommendations have been made for survey statisticians intending to apply these findings to real-life problems.

NOx formation processes in rotating detonation engines

High-fidelity simulations of RDEs with H2-Air-NOx chemistry are employed to study NOx emissions in such devices. Discrete injection of gaseous hydrogen fuel and continuous injection of air oxidizer is used at various mass flow rate conditions in several 3D RDE simulations to understand resulting NOx production behaviors. Simulations are also performed for two different injector configurations, one in which air is injected axially into the detonation chamber [Axial Air Inlet (AAI)] and one in which air is injected radially [Radial Air Inlet (RAI)]. It is seen that the AAI RDE produces much less NOx than the RAI RDE, mainly due to the weaker waves seen in this system as a result of parasitic combustion losses from product gas recirculation. Parasitic combustion does lead to NOx formation in its own right, but the emissions levels from this process are negligible compared to emissions stemming directly from detonation processes. In regards to detonation strength in particular, it is generally seen that detonation strength increases with increasing mass flow rate, in turn increasing peak pressure, peak heat release and NOx emissions levels. Nevertheless, even the highest recorded NOx levels at the combustor exit in this study remain on the same order of magnitude as compared to gas turbine exhaust emissions levels, supporting the claim that significant differences between detonative and deflagrative combustion do not necessarily lead to significant differences in NOx levels. Overall, this study provides greater understanding into the behaviors of NOx formation in RDEs and how these behaviors are affected by changes in operating parameters.

Operation and control of compact offshore combined cycles for power generation

Gas turbines are the main means for generating power in offshore installations. To increase energy efficiency, and thus reduce CO2 emissions, a steam bottoming cycle can be added to produce additional power by recovering surplus heat from the gas turbine exhaust. Due to space constraints, this solution is not widespread for offshore power generation. To enable deployment, the system must be compact and be able to provide varying power demands. In this paper, we analyze the operation and control problem for such compact combined cycles, consisting of two gas turbines and one steam bottoming cycle. We analyze the steady-state performance of the combined cycle with respect to efficiency and CO2 emissions for two control strategies for coordinating the power setpoint of the two gas turbines. Equal load allocation of the gas turbines showed a higher thermal efficiency and lower emissions compared to keeping one gas turbine close to nominal and letting the second one handle load variations. The main controlled variables for the steam bottoming cycle are the superheated steam pressure and temperature. We implement decentralized control strategies based on standard PID-controllers and nonlinear feedforward. Due to reduced throttle losses, sliding pressure shows higher efficiency and lower CO2 emissions compared to keeping a constant steam pressure, which conversely provides a better temperature dynamic response and may be necessary with highly varying power demand.

Effect of inlet conditions on the thermal insulation performance of marine gas turbine exhaust systems

A marine gas turbine insulation solution was designed to reduce exhaust system temperatures. The effects of cooling gas temperature (45?C, 55?C, 65?C), cooling air velocity (2 m/s - 10 m/s), and a range of classic aerodynamic conditions ranging on the thermal insulation performance of the gas turbine exhaust system were investigated using numerical simulations. The results indicate that the use of aerogel insulation material effectively reduces the average temperature of the exterior volute casing to 71?C from 315?C under rated turbine conditions. The exterior volute casing temperature increases with higher cooling gas inlet temperatures but decreases with increasing cooling gas inlet velocities. Additionally, alterations in the aerodynamic conditions at the gas inlet will induce changes in the thermal insulation performance of the exhaust system, and excessive circumferential flow velocities can cause localized overheating in the exhaust volute casing.

Digital twin modeling and operation optimization of the steam turbine system of thermal power plants

The increasing deployment of renewable energy sources necessitates peak regulation services from thermal power plants, impacting their energy efficiency. Central to these plants, the steam turbine system significantly influences their operational efficiency. A digital twin model of this system was developed, integrating mechanism-driven and data-driven modeling methods. The neural network data-driven approach was specifically utilized for parameters such as feedwater pump speed and steam flow rate to the pump turbine. Other parameters were modeled with mechanism data hybrid driven modeling method. This model computes vital metrics such as low-pressure turbine exhaust steam enthalpy, work done and heat absorption per unit mass of steam, system efficiency, feedwater mass flow rate, and water-coal ratio—key for evaluating and enhancing the system's energy efficiency. An investigation into a reference case showed a decline in efficiency below design levels due to aging. By optimizing the live steam pressure and the cold-end system, relative improvements in energy efficiency of 0.35 % and 0.14 %, respectively, were achievable.