Indonesian National Electricity Company (PT.PLN (Persero)) has planned to install additional high voltage undersea cable for circuit llI and IV Java-Bali to fulfill electricity demand in Bali. This project was mor...Indonesian National Electricity Company (PT.PLN (Persero)) has planned to install additional high voltage undersea cable for circuit llI and IV Java-Bali to fulfill electricity demand in Bali. This project was more prefered compared to building another power plant in Bali which could raise social and cultural resistance. Life cycle cost method was used to complete the financial feasibility study to ensure if the project has economic benefit, and the asset would be used effectively and efficiently along its benefit period. In this paper, a life cycle cost will be simulated to analyze which alternative is the most profitable: installation circuit III and IV in 2012 or installation circuit III in 2012 and circuit IV in 2017 in accordance with load forecasting demand. This study is used to help the management to make a decision about the project.展开更多
The financial viability of a solar STES (seasonal thermal energy store) installed in a mixed commercial and residential multiunit development of low-energy buildings located in Lysekil, Sweden, a maritime Scandinavi...The financial viability of a solar STES (seasonal thermal energy store) installed in a mixed commercial and residential multiunit development of low-energy buildings located in Lysekil, Sweden, a maritime Scandinavian Climate has been investigated. Using recorded figures for the installation costs and performance, a financial life cycle analysis has been undertaken to determine the cost effectiveness of the system. The time value of money is considered and an LCC (life cycle cost) analysis undertaken to identify the cost-effectiveness of the solution. It shows that while a direct heating and hot water system incorporating STES can be economically viable in a Swedish maritime climate in the long term, assistance such as that provided by government incentives is required to assist with the high capital cost of the initial investment.展开更多
In the present paper,extremely unsteady shock wave buffet induced by strong shock wave/boundary-layer interactions (SWBLI) on the upper surface of an OAT15A supercritical airfoil at Mach number of 0.73 and angle of at...In the present paper,extremely unsteady shock wave buffet induced by strong shock wave/boundary-layer interactions (SWBLI) on the upper surface of an OAT15A supercritical airfoil at Mach number of 0.73 and angle of attack of 3.5 degrees is first numerically simulated by IDDES,one of the most advanced RANS/LES hybrid methods.The results imply that conventional URANS methods are unable to effectively predict the buffet phenomenon on the wing surface;IDDES,which involves more flow physics,predicted buffet phenomenon.Some complex flow phenomena are predicted and demonstrated,such as periodical oscillations of shock wave in the streamwise direction,strong shear layer detached from the shock wave due to SWBLI and plenty of small scale structures broken down by the shear layer instability and in the wake.The root mean square (RMS) of fluctuating pressure coefficients and streamwise range of shock wave oscillation reasonably agree with experimental data.Then,two vortex generators (VG) both with an inclination angle of 30 degrees to the main flow directions are mounted in front of the shock wave region on the upper surface to suppress shock wave buffet.The results show that shock wave buffet can be significantly suppressed by VGs,the RMS level of pressure in the buffet region is effectively reduced,and averaged shock wave position is obviously pushed downstream,resulting in increased total lift.展开更多
文摘Indonesian National Electricity Company (PT.PLN (Persero)) has planned to install additional high voltage undersea cable for circuit llI and IV Java-Bali to fulfill electricity demand in Bali. This project was more prefered compared to building another power plant in Bali which could raise social and cultural resistance. Life cycle cost method was used to complete the financial feasibility study to ensure if the project has economic benefit, and the asset would be used effectively and efficiently along its benefit period. In this paper, a life cycle cost will be simulated to analyze which alternative is the most profitable: installation circuit III and IV in 2012 or installation circuit III in 2012 and circuit IV in 2017 in accordance with load forecasting demand. This study is used to help the management to make a decision about the project.
文摘The financial viability of a solar STES (seasonal thermal energy store) installed in a mixed commercial and residential multiunit development of low-energy buildings located in Lysekil, Sweden, a maritime Scandinavian Climate has been investigated. Using recorded figures for the installation costs and performance, a financial life cycle analysis has been undertaken to determine the cost effectiveness of the system. The time value of money is considered and an LCC (life cycle cost) analysis undertaken to identify the cost-effectiveness of the solution. It shows that while a direct heating and hot water system incorporating STES can be economically viable in a Swedish maritime climate in the long term, assistance such as that provided by government incentives is required to assist with the high capital cost of the initial investment.
基金supported by EU Project Advanced Turbulence Simulation for Aerodynamic Application Challenges (Grant No.ACP8-GA-2009-233710)the National Natural Science Foundation of China (Grant Nos.11072129 and 10932005)
文摘In the present paper,extremely unsteady shock wave buffet induced by strong shock wave/boundary-layer interactions (SWBLI) on the upper surface of an OAT15A supercritical airfoil at Mach number of 0.73 and angle of attack of 3.5 degrees is first numerically simulated by IDDES,one of the most advanced RANS/LES hybrid methods.The results imply that conventional URANS methods are unable to effectively predict the buffet phenomenon on the wing surface;IDDES,which involves more flow physics,predicted buffet phenomenon.Some complex flow phenomena are predicted and demonstrated,such as periodical oscillations of shock wave in the streamwise direction,strong shear layer detached from the shock wave due to SWBLI and plenty of small scale structures broken down by the shear layer instability and in the wake.The root mean square (RMS) of fluctuating pressure coefficients and streamwise range of shock wave oscillation reasonably agree with experimental data.Then,two vortex generators (VG) both with an inclination angle of 30 degrees to the main flow directions are mounted in front of the shock wave region on the upper surface to suppress shock wave buffet.The results show that shock wave buffet can be significantly suppressed by VGs,the RMS level of pressure in the buffet region is effectively reduced,and averaged shock wave position is obviously pushed downstream,resulting in increased total lift.