Modification of Culvert Design on Discharge Channel: A Case Study in Indonesian Coal-Fired Power Plant

The construction of a new CFPP in Indonesia, which was located next to three existing power plants and utilized an existing discharge channel, faced the problem of insufficient capacity of the existing discharge channel to deliver water to four power plants. The problem occurred not only because of the overcapacity of the cooling water flow proposed by the new CFPP but also because of the small size of the culvert located in the discharge channel. This paper discusses several methods to overcome this problem by enlarging the culvert area or by removing the culvert from the channel and replacing it with a bridge. A hydraulic study was investigated using the HEC-RAS software by utilizing inputs obtained from the existing channel geometry and flow measurement data. It was found that additional culverts on both sides with a size of 2 m x 4 m and 3 m x 1 m could reduce the water level by 1.12 m and 0.39 m, respectively. Meanwhile, removing the culvert provided a significant water level reduction of 1.39 m. Enlarging the culvert was chosen as the solution to the discharge channel capacity issue since removing the culvert would require temporarily closing the channel during construction and stopping the operation of the existing power plant

Modification of Culvert Design on Discharge Channel: A Case Study in Indonesian Coal-Fired Power Plant

The construction of a new CFPP in Indonesia, which was located next to three existing power plants and utilized an existing discharge channel, faced the problem of insufficient capacity of the existing discharge channel to deliver water to four power plants. The problem occurred not only because of the overcapacity of the cooling water flow proposed by the new CFPP but also because of the small size of the culvert located in the discharge channel. This paper discusses several methods to overcome this problem by enlarging the culvert area or by removing the culvert from the channel and replacing it with a bridge. A hydraulic study was investigated using the HEC-RAS software by utilizing inputs obtained from the existing channel geometry and flow measurement data. It was found that additional culverts on both sides with a size of 2 m x 4 m and 3 m x 1 m could reduce the water level by 1.12 m and 0.39 m, respectively. Meanwhile, removing the culvert provided a significant water level reduction of 1.39 m. Enlarging the culvert was chosen as the solution to the discharge channel capacity issue since removing the culvert would require temporarily closing the channel during construction and stopping the operation of the existing power plant

PEMODELAN NUMERIK 3-DIMENSI ALIRAN PADA SALURAN TERBUKA MELEWATI STRUKTUR BOTTOM INTAKE

Bottom intake is a simple structure which is consist of a channel on the river bottom vertical to the river flow and a screen on top of the channel. Kamanbedast and Bejestan (2008) was conducted the research to know the optimum intake slope by using physical model. The optimum intake slope was taken by the ratio of discharge entering the intake to the discharge fromupstream. Based on 4 slope variation (10, 20, 30 and 40%), it is obtained the optimum slope at 30%. Considering the limitation of bottom intake slope variation, it is possible that the optimum slope occurs at the range between 20 to 30%or 30 to 40%. The present research uses 3-dimensional numerical model by the support of Flow3D programming package. The simulation was conducted at various slope with the accuracy of 1%. The result shows the optimum slope at 28% with the discarge ratio as 28,3%

Mathematical Modeling-Based Management of a Sand Trap throughout Operational and Maintenance Periods: Case Study Pengasih Irrigation Network, Indonesia

Surface irrigation networks in Indonesia are damaged by several factors, and sedimentation is among the most severe challenges. Sand traps play a substantial role in improving irrigation system efficiency by reducing sedimentation. There are two periods in sand trap operation: the operational and maintenance periods. Pengasih is one of the irrigation schemes implemented in the Progo Opak Serang (POS) River Basin, which has a high level of erosion. This study aimed to propose an appropriate management strategy for the Pengasih sand trap as the first barrier in irrigation network sedimentation based on mathematical modeling. The HEC-RAS simulation software was used to simulate the sand trap hydraulic behaviour. The results show that the validated Manning’s coefficient was 0.025. The optimal transport parameters were Laursen for the potential function, Exner 5 for the sorting method, and Rubey for the fall velocity method. The recommended flushing timeframe is 315 min, with a discharge of 2 m3/s. We suggest that the sand trap flushing frequency be performed twice a year, and it can be performed at the end of March and October. This coincides with the end of the first and third planting seasons of the irrigation scheme. © 2022 by the authors

Mathematical Modeling-Based Management of a Sand Trap throughout Operational and Maintenance Periods (Case Study: Pengasih Irrigation Network, Indonesia)

Surface irrigation networks in Indonesia are damaged by several factors, and sedimentation is among the most severe challenges. Sand traps play a substantial role in improving irrigation system efficiency by reducing sedimentation. There are two periods in sand trap operation: the operational and maintenance periods. Pengasih is one of the irrigation schemes implemented in the Progo Opak Serang (POS) River Basin, which has a high level of erosion. This study aimed to propose an appropriate management strategy for the Pengasih sand trap as the first barrier in irrigation network sedimentation based on mathematical modeling. The HEC-RAS simulation software was used to simulate the sand trap hydraulic behaviour. The results show that the validated Manning’s coefficient was 0.025. The optimal transport parameters were Laursen for the potential function, Exner 5 for the sorting method, and Rubey for the fall velocity method. The recommended flushing timeframe is 315 min, with a discharge of 2 m3/s. We suggest that the sand trap flushing frequency be performed twice a year, and it can be performed at the end of March and October. This coincides with the end of the first and third planting seasons of the irrigation scheme