Abstract: An idea of introducing an underground floodway inspired by Storm-water Management and Road Tunnel (SMART) in Malaysia is considered attractive to minimize land utilization regarding to the flood problem in Jakarta. This research was aimed to know the flow behavior of this modified tunnel due to sudden transitions, pressure losses and loss coefficients using numerical modeling. The simulation was conducted in the three-dimensional model using FLUENT Software which was divided into three models, i.e., contraction, enlargement, and straight pipe model. The simulation model was followed the geometrical design of SMART which the area ratio between smaller and larger pipe, A1/A2 varied, namely 0.20, 0.50, and 0.80. Standard k-ε and equilibrium wall function were used in straight pipe model, while contraction and enlargement model used k-ε modified and non-equilibrium wall function. The effect of different Reynolds number was also studied in this research. The result of the simulation showed that hydraulic parameters and area ratio of sudden transitions pipe give significant effect towards losses along the pipe. FLUENT simulation result gave good agreement with Darcy-Weisbach formula. The results indicate that loss coefficient decreases with the increase in pipe area ratio. The increase in pressure head loss was incurred by severe separated regions in the vicinity of pipe transition which was proved by typical flow pattern. Variation of Reynolds number also showed a different area of separation flow, yet the flow pattern was somewhat similar.
Abstract: A simple numerical model has been generated for developing a code of Smoothed Particle Hydrodynamics (SPH) method. Those will be modified and used for future research. In this computational research domain is a square that consists of a real particle and virtual particle as the boundary treatment. In the initial condition, particle occupies a certain position. Circular flow has been generated by a rotating vertical cylinder to produce shear velocity to the real particle. The particles movement has been observed during time integration. A physical model has been constructed to compare the numerical model. The movement of real particles on the numerical model agrees with the movement of water particles on the physical model.
Abstract: Darcy was known as a very generous engineer. He is undoubtedly the father of the science of fluid flow in soils for his experiment on the flow of water through a sand column which was published in his book ‘Les fontaines publiques de la ville de Dijon in 1856, named after him as Darcy’s law. For the practical computation, this equation was developed by Dupuit & Thiem, and then it called Dupuit-Thiem equation. This equation was redeveloped by many researchers in many variations with different parameters especially for radial flow in pumping and recharging systems. Their basic pumping system equations for a confined and unconfined aquifer as well as for full penetration well with a fully perforated casing. In the practical implementation, this condition rarely occurs especially for thick aquifer; therefore many researchers developed a correction for those formulas from full penetration to be partial penetration wells. Partial penetration well is a well which its depth or tip of its casing does not reach an impermeable stratum beneath the aquifer. Despite the correction, those formulas still have difficulty in computing the design of pumping system due to its need for hydraulic gradient data which can only be defined by two real time data of piezometric head before and after pumping related to the horizontal distance of both points. So in this paper will be presented some inventions of computation methods for instance: recharge systems, the drawdown of pumping, pumping on the aquifer, water losses on the lake, permeability test, pumping test analysis and partial penetration well equation.
Abstract: Short duration rainfall information has now become one of many important aspects to support the development of warning criteria for disaster mitigation. Similar importance is also found in the development of warning criteria against the lahar flow disaster at Mt. Merapi area. The rainfall information obtained from the radar observation has also become a new challenge for the last decade in line with the rapid growth of information and communication technology. However, the accuracy of its estimation needs to be evaluated by considering the correlation between radar rainfall and rain gauge rainfall. In case of radar rainfall can be precisely estimated, this information will contribute to generating appropriate warning criteria. This study was carried out as the first attempt to evaluate the rainfall information as performed by the X-Band Multi Parameter Radar (XMPR) that was installed at Mt. Merapi in the mid-August 2015. Several ground rainfall data obtained from Automatic Rainfall Recorder (ARR) have been adopted to analyze the aforesaid radar rainfall information, and estimated errors between the two are presented. Evaluation of the radar estimated error value as a function or range is taken through a Fractional Standard Error (FSE) index that quantifies the differences between ground rainfall measurement (G) and radar rainfall estimation (R), also the G/R ratio characteristics. The result shows there was a poor correlation between radar estimated and rain gauge measured rainfall located over 14 km from radar. Radar bias (M) is suitable for correcting radar rainfall amount, yet inappropriate for fractional values.
Abstract: TiO2 film has been applied as UV-TiO2 photocatalytic batch reactor to degrade total organic carbon (TOC) in peat water for prolonged use. TOC was degraded as 99% after irradiation for six hours and water became neutral. In this study, solar UV-TiO2 photocatalytic reactor continuous system has been designed as the development of a batch system. Five reactor batches each are coated with TiO2 film that arranged vertically, filled with peat water. Peat water is drained from the top batch of reactors to the reactor batch underneath continuously by vertical pumps. The vertical pump is equipped with a flow rate regulating valve due to peat water can interact optimally with TiO2 films in each batch during the reaction. Humic compounds in peat water that absorb on TiO2 films can be degraded photocatalitically by the energy of photons from sunlight (solar). Solar continuous reactors system will be very effective and efficient to be developed to degrade peat water into clean water, for saving energy and water degradation products free of harmful chemicals due to green process.
Abstract: Although the source of drinking water is abundantly available in East Lombok District, its quality raises a public health concern. The East Lombok District, especially Teros Village at Labuhan Haji District is mainly characterized by several springs and very shallow water levels. Teros village communities regularly use water from springs or from dug wells to meet their daily needs. The springs are scattered and located in the middle of densely populated settlements. This results in the high possibility of groundwater contamination or pollution by human activities. This research primarily aims at studying the microbiological water quality of drinking water at Teros Village, and to review household water treatments methods employed by the local population and also the sanitation condition. Eight water samples were taken from six dug wells and two springs and were analyzed with measured microbiological parameters namely coliform and fecal coli. It is revealed that there is a significant degree of microbiological pollution of drinking water in this area owing to domestic wastewater and poor sanitation condition. By using purposive sampling technique, 100 respondents (Head of Family) were selected to collect qualitative data regarding local household water treatment methods. This amount based on the reason that one house with one water source is usually inhabited and used by some families so that the number of respondents is considered enough to represent the existing conditions. Field observation was conducted to find out the sanitation condition. Local residents were familiar with several household water treatments methods, although they only knew about limited physical characteristics of water improvement.
Abstract: Green Campus is a campus environment that is designed to increase energy efficiency, preserve resource and improve the quality of the environment. One of the important elements to support the green campus program is the existence of drinking water supply system.Universitas Gadjah Mada Drinking Water Supply System (UGM-DWSS) is a drinking water or potable water supply service to supply drinking water for the campus. This research aims at analyzing UGM-DWSS potential and its performance to support Green Campus. This research was based on primary data collection in UGM campus. Data collection techniques consist of observation of UGM-DWSS facilities, interview with UGM-DWSS water managers and users, and questionnaires distribution to UGM academic community. The daily water production of UGM-DWSS was 10 l/s drinking water. Every day the water discharge distributed from UGM-DWSS to 49 water fountains and 12 water dispensers was1.71 l/s, while the estimated daily water consumption rate was0.07l/s. It is assumed that those who did not consume water from UGM-DWSS facilities bought plastic drinking water bottle. Every day, it is estimated that the number of generated plastic drinking water bottle waste was 19,168 bottles with capacity 600 ml/bottle. Indeed, by comparing to the total water production capacity being produced daily, the idle capacity was 99.3 %.The tendency of negative response from the majority of UGM inhabitants for using UGM –DWSS was due to hesitation about water quality, continuity of water supply, and ease of access to the nearby water fountains and water dispensers. Improvement of UGM-DWSS facilities that are supported by massive socialization programs including innovation to utilize produced drinking water is recommended to optimize the role of UGM-DWSS to create Green Campus.
Abstract: The decent quality, quantity, and continuity of Drinking Water Supply System (DWSS) are needed to support the activities of a campus. Universitas Gadjah Mada drinking water supply system (UGM-DWSS) provides 49 Water Fountains (WF) and 12 Water Dispensers (WD) to support daily activities for all the campus community. This research aimed at figuring out the performance of the existing UGM-DWSS against the current service pipeline distribution network so that the technical condition of the pipes’ pressure, the water consumption’s discharge, and the pumps’ use can be identified. The method used for analyzing is by implementing simulating the network performance using WaterNet program version 2.2 by which pipes network and its facilities performance including optimization of pipe diameter can be described. The simulation indicated that there was 80% idle capacity of the available water capacity. It is uneconomical to make any changes to the existing pipes’ condition considering the very high cost of the pipeline construction. Therefore, pump replacement was considered more feasible optimization approach. To obtain the optimal results, the pump should be replaced with 4 m3/hours capacity with 20 meters pump design head.
Abstract: CWSS in Kotamobagu has various problems such as, pipe water network that has not been operated optimally since its completion in 2012. The number of house connections was merely 424 out of 7,600 targeted until 2016. Other problems in Kotamobagu were related to the supply, backwash, insufficient electrical power supply, no water meter, reservoir leakage, and intake pipes leakage in Poyowa and Bilalang. This research aims to find the root of the problem in terms of Clean Water Supply System (CWSS)'s network system, organization, regulation, and management. The research focused on Poyowa Besar's CWSS and Bilalang-1's CWSS networks in Kotamobagu. The research methods included observation, survey, and policy analysis where respondents were required as sources of information. The respondents were from Sia's and Pontodon's CWSS that represented 162 house connections. Additional respondents representing 30 house connections were selected randomly at Poyowa Besar's and Bilalang-1's CWSS for comparison. The results indicated that the community, CWSS managers, and the Central Government support the existence of Kotamobagu CWSS management. The 30 house connections at Poyowa Besar's and Bilalang-1's CWSS have never been served with water, but the respondents positively hope that the matter will be solved in the near future. They were willing to keep waiting for the water network of Kotamobagu's CWSS. The root of the problem in the Poyowa Besar's and Bilalang-1's implementation was due primarily to a network system that was built by the Ministry of Public Works for the Municipal Government of Kotamobaguwas reportedly not in accordance with procurement regulation. There was disagreement between the Ministry of Public Works and Housing (MPWH) and the CWSS managers related to the items that have to be fulfilled for network infrastructure handover.