Modeling and performance enhancements of a gas turbine combined cycle power plant

This thesis deals with modelling and performance enhancements of a gas-turbine combined cycle power plant. A clean and safe energy is the greatest challenges to meet the requirements of green environment. These requirements given way the long time governing authority of steam turbine (ST) in the world power generation, and gas turbine (GT) and its combined cycle (CCGT) will replace it. Therefore, it is necessary to predict the characteristics of the CCGT system and optimize its operating strategy by developing a simulation system. Several configurations of the GT and CCGT plants systems are proposed by thermal analysis. The integrated model and simulation code for exploiting the performance of gas turbine and CCGT power plant are developed utilizing MATLAB code. New strategies for GT and CCGT power plant's operational modelling and optimizations are suggested for power plant operation, to improve overall performance. The effect of various enhancing strategies on the performance of the CCGT power plant (two-shaft, intercooler, regenerative, reheat, and multi-pressure heat recovery steam generator (HRSG)) based on the real GT and CCGT power plants. An extensive thermodynamic analysis of the modifications of the most common configuration's enhancements has been carried out. The performance code for heavy-duty GT and CCGT power plants are validated with the real power plant of Baiji GT and MARAFIQ CCGT plants the results have been satisfactory. The simulating results show that the reheated GT has a higher power (388MW) while the higher thermal efficiency occurs in the regenerative GT (52%) with optimal pressure ratio and turbine inlet temperature. The performance enhancing strategies results show that the higher power output occurs in the intercooler-reheat GT strategy (404MW). Furthermore, the higher thermal efficiency (56.9%) and lower fuel consumption (0.13kg/kWh) occur in the intercooler-regenerative-reheat GT strategy. The analyses of the HRSG configurations show that the maximum power output (1238MW) occurred in the supplementary triple pressure with reheat CCGT while the overall efficiency was about 56.6%. The intercooler-reheat CCGT strategy has higher power output (1637MW) and the higher overall thermal efficiency (59.4%) and lower fuel consumption (0.047kg/kWh) occur with the regenerative-reheat CCGT strategy. The simulation result shows that the proposed GT system improved 19% of thermal efficiency and 22% of power output. In addition, the proposed CCGT system improved 4.6% of thermal efficiency for and 22.5% of power output. The optimization result shows that the optimum power (1280MW) and the overall thermal efficiency (65%) of the supplementary triple pressure with reheat CCGT. Therefore, the optimization procedure is reasonably accurate and efficient. Thus, the operation conditions and ambient temperature are strongly influenced on the overall performance of the GT and CCGT. The optimum efficiency and power are found at higher turbine inlet temperatures. It can be comprehended that the developed models are powerful tools for estimating the overall performance of the CCGT plants. The energy and exergy analysis models for the GT and CCGT plants are highly recommended for predicting them performance based on inlet air cooling system

LIFE CYCLE ASSESSMENTSOF GAS TURBINE USING INLET AIR COOLING SYSTEM

To achieve a life cycle assessments of energy systems with both power output and economical profits maximized is considered as the main objective of operation management. This paperis designedto evaluate boththe performance of agas turbine added with an inlet air cooling system as well as its life cycle cost. Accordingly, a thermodynamic model and an economic model are developed respectively to derive an analytical formula for calculating the cooling loads and life cycle cost. The majorresults show that the output power for gas turbine power plant with the cooling system (120MWH) is higher than that of a gas turbine power plant without the cooling system (96.6 MWh) at peak condition; while the life cycle cost of former plants is lower thanthe latter ones.Thus, the proposed methods suggest potential cost-effective improvements feasible and achievable through changing the structure of the system.</p

Investigation on the performance of a prototype of thermo-electric generation with heat pipe-heat sink

A significant problem in thermo-electric generators is the thermal design of the heat sink because it affects the performance of thermo-electric modules. As compared to conventional cooling systems, heat pipe heat sink have numerous advantages. Some of these advantages are: high heat-transfer rates; absence of moving parts and lack of auxiliary consumption (passive system). This paper presents the analysis of power generation using the combination of heat pipes and thermo-electric generators. The aim is to improve power output by an appropriate design of the heat sink. The average geometrical parameters of heat sink (fin height, fin space and fin thickness) were obtained from data collected from previous studies closely similar to this prototype. The prototype was tested and the temperature, voltage and current data were collected. All data were recorded by using a temperature data recorder, power meter and multimeter. It was found that the highest maximum power output was 1.925 watts at a temperature difference of 85°C. However, the prototype did not achieve the maximum output expected. This was a result of limitation of TEG model (where only one TEG was used) and the limitation of the performance of the prototype. The prototype successfully generated enough power to charge a cell phone and laptop when connected to two or three TEGs. Moreover the heat pipe heat sink needs optimization to meet the design output from the manufacturer of the TEG at hot side temperature and cold side temperature

A Study On The Power Generation Potential Of Mini Wind Turbine In East Coast Of Peninsular Malaysia

A small-scale wind turbine is an attractive renewable energy source, but its economic viability depends on wind speed. The aim of this study is to determine economic viability of small-scale wind turbine in East Coast of Peninsular Malaysia. The potential energy generated has been determined by wind speed data and power curved of. Hourly wind speed data of Kuantan throughout 2015 was collected as the input. Then, a model of wind turbine was developed based on a commercial a 300W mini wind turbine. It was found that power generation is 3 times higher during northeast monsoon season at 15 m elevation. This proved that the northeast monsoon season has higher potential in generating power by wind turbine in East Coast of Peninsular Malaysia. However, only a total of 153.4 kWh/year of power can be generated at this condition. The power generator utilization factor PGUI was merely 0.06 and it is not technically viable. By increasing the height of wind turbine to 60 m elevation, power generation amount drastically increased to 344 kWh/year, with PGUI of 0.13. This is about two-thirds of PGUI for photovoltaic technology which is 0.21 at this site. If offshore condition was considered, power generation amount further increased to 1,328 kWh/year with PGUI of 0.51. Thus, for a common use of mini wind turbine that is usually installed on-site at low elevation, it has low power generation potential. But, if high elevation as what large wind turbine needed is implemented, it is technically viable option in East Coast of Peninsular Malaysia

Enhancing the performance of a thermo-electric generator through multi-objective optimisation of heat pipes-heat sink under natural convection

Heat sink lack of design is one reason that negatively affects the performance of Thermo-Electric Generator (TEG). As compared to conventional cooling systems used with TEG, Heat Pipe Heat Sink (HP-HS) has various points of interest. It is the most appropriate heat exchanger for medium temperature range under 300 °C. However, the performance of TEG with HP-HS could be affected by the fin space, fin length, fin height, fin materials and optimum geometry of HP-HS of the TEG cold side, which is still unknown. Thus, the aim of this study is to conduct an analytical and statistical study on the effects of fins space, fins length, fins height and fin materials parameters on the performance of TEG. In addition, the optimum geometry of HP-HS was investigated. The experimental study has been carried out with different dimensions of fin space, fin length and fin height, depending on the range determined based on previous studies. Besides, two materials were used namely aluminum (AL) and copper (CO). The multi-objective optimisation using response surface methodology (RSM) is applied to determine the optimum geometry of HP-HS to maximise the TEG power output (P), TEG efficiency (η), and to minimise HP-HS cost ($). The responses developed models were determined to be significant at 95% confidence level. It was found that an improvement in TEG performance as compared to literature was achieved. The maximum P and η after optimisation were 8.2 W and 3%, respectively. The percentage difference of TEG η as compared with the best previous results were, 36.7%. In addition, the CO HP-HS was found to be preferred over AL because of its lower costs per power output. CO was 8.75 USD/W, whilst, AL was 10.13 USD. Finally, this study shows an improvement in HP-HS cost, a reduction by 17.9% was achieved when compared with the estimated HP-HS cost in literature

Development of Innovative Coating Methods for Metal Based Roof

 Metal panels are one of the most common roofs covering in Malaysian buildings. Nevertheless, the commercial metal roof is generally known as not being effective enough in reflecting sunlight and emitting thermal energy. Hence, innovative coating solutions were developed and analysed in terms of their thermal performance. Seashells and woodchips were used as the raw materials to develop the innovative coating. Thermocouple modules were integrated with Arduino to measure the surface temperatures of 3 roof prototype, Prototype A (commercial metal panel), Prototype B (with woodchips coating) and Prototype C (with seashells coating). Their temperature profiles were investigated, and their thermal performance was analysed, and from that, the overall heat transfer coefficient (U value) was calculated. It was found that temperature for Prototype C was the lowest in the range of 32 to 50ºC, while Prototype A were in the range of 32 to 60ºC, and there is no significant difference between prototype A and B. In addition, temperature difference for Prototype C are always in positive values, reaching as high as 6ºC in the afternoon. The other 2 prototypes fluctuated between the range of - 4ºC and 4ºC. These results were proved with the U-values calculated in which UA was 217 W/m2K, UB was 44 W/m2K and UC is 69.6 W/m2K. However, UB contradicts with the temperature profile results. Overall, Prototype C, with seashells coating shows promising results as material of innovative roof based coating

Development of Innovative Coating Methods for Metal Based Roof

 Metal panels are one of the most common roofs covering in Malaysian buildings. Nevertheless, the commercial metal roof is generally known as not being effective enough in reflecting sunlight and emitting thermal energy. Hence, innovative coating solutions were developed and analysed in terms of their thermal performance. Seashells and woodchips were used as the raw materials to develop the innovative coating. Thermocouple modules were integrated with Arduino to measure the surface temperatures of 3 roof prototype, Prototype A (commercial metal panel), Prototype B (with woodchips coating) and Prototype C (with seashells coating). Their temperature profiles were investigated, and their thermal performance was analysed, and from that, the overall heat transfer coefficient (U value) was calculated. It was found that temperature for Prototype C was the lowest in the range of 32 to 50ºC, while Prototype A were in the range of 32 to 60ºC, and there is no significant difference between prototype A and B. In addition, temperature difference for Prototype C are always in positive values, reaching as high as 6ºC in the afternoon. The other 2 prototypes fluctuated between the range of - 4ºC and 4ºC. These results were proved with the U-values calculated in which UA was 217 W/m2K, UB was 44 W/m2K and UC is 69.6 W/m2K. However, UB contradicts with the temperature profile results. Overall, Prototype C, with seashells coating shows promising results as material of innovative roof based coating

A New Dewatering Technique for Stingless Bees Honey

One of the problems faced in stingless bee honey storage is spoilage by the fermentation process occurs in honey due to its high water content. There are a few techniques available currently, but they are time consuming and there is excessive heat involved in the process. The temperature of the process must be kept low because excessive heat can deteriorate nutrition value and biochemical content in honey. Hence, a new method of honey dewatering was developed using a Low Temperature Vacuum Drying (LTVD) with induced nucleation technique. The objective of this research is to investigate the performance of a LTVD with induced nucleation to reduce the water content in honey. First, the honey was placed in a pressure vessel, and then air was removed. Then, the honey was slightly heated at 30 ºC and the water content before and after the experiment was measured by a refractometer. The steps were repeated until the water content reached below 20%. It was found that the LTVD method improved the water removal rate significantly with an average of 0.15% of water content per minute. That is 3 times much faster than the conventional method of low temperature heating by Tabouret. Higher temperature during dewatering process improved the dewatering rate significantly. It can be concluded that LTVD is a promising option in tackling the high water content in stingless bee honey issue

A new dewatering technique for stingless bees honey

One of the problems faced in stingless bee honey storage is spoilage by the fermentation process occurs in honey due to its high water content. There are a few techniques available currently, but they are time consuming and there is excessive heat involved in the process. The temperature of the process must be kept low because excessive heat can deteriorate nutrition value and biochemical content in honey. Hence, a new method of honey dewatering was developed using a Low Temperature Vacuum Drying (LTVD) with induced nucleation technique.The objective of this research is to investigate the performance of a LTVD with induced nucleation to reduce the water content in honey. First, the honey was placed in a pressure vessel, and then air was removed. Then, the honey was slightly heated at 30°C and the water content before and after the experiment was measured by a refractometer. The steps were repeated until the water content reached below 20%. It was found that the LTVD method improved the water removal rate significantly with an average of 0.15% of water content per minute. That is 3 times much faster than the conventional method of low temperature heating by Tabouret. Higher temperature during dewatering process improved the dewatering rate significantly. It can be concluded that LTVD is a promising option in tackling the high water content in stingless bee honey issue

A new dewatering technique for stingless bees honey

One of the problems faced in stingless bee honey storage is spoilage by the fermentation process occurs in honey due to its high water content. There are a few techniques available currently, but they are time consuming and there is excessive heat involved in the process. The temperature of the process must be kept low because excessive heat can deteriorate nutrition value and biochemical content in honey. Hence, a new method of honey dewatering was developed using a Low Temperature Vacuum Drying (LTVD) with induced nucleation technique.The objective of this research is to investigate the performance of a LTVD with induced nucleation to reduce the water content in honey. First, the honey was placed in a pressure vessel, and then air was removed. Then, the honey was slightly heated at 30°C and the water content before and after the experiment was measured by a refractometer. The steps were repeated until the water content reached below 20%. It was found that the LTVD method improved the water removal rate significantly with an average of 0.15% of water content per minute. That is 3 times much faster than the conventional method of low temperature heating by Tabouret. Higher temperature during dewatering process improved the dewatering rate significantly. It can be concluded that LTVD is a promising option in tackling the high water content in stingless bee honey issue