Journal of the Serbian Society for Computational Mechanics

Journal of the Serbian Society for Computational Mechanics

Journal of the Serbian Society for Computational Mechanics is the official journal of the SERBIAN SOCIETY FOR COMPUTATIONAL MECHANICS (SSCM), member of International Association for Computational Mechanics (IACM) and European Community on Computational Methods in Applied Sciences (ECCOMAS).

U okviru časopisa Volume 3, broj 1 iz 2009. godine objavljeno je pet radova.

HYDRO-INFORMATION SYSTEMS AND MANAGEMENT OF HYDROPOWER RESOURCES IN SERBIA

D. Divac, N. Grujović, N. Milivojević, Z. Stojanović, Z. Simić

SWAT-BASED RUNOFF MODELING IN COMPLEX CATCHMENT AREAS – THEORETICAL BACKGROUND AND NUMERICAL PROCEDURES

Simić, N. Milivojević, D. Prodanović, V. Milivojević, N. Perović

HYDRO-METEOROLOGICAL DATA QUALITY ASSURANCE AND IMPROVEMENT

N. Branisavljević, D. Prodanović, M. Arsić, Z. Simić, J. Borota

DISCRETE EVENTS SIMULATION MODEL APPLIED TO LARGE-SCALE HYDRO-SYSTEMS

Milivojević, N. Grujović, B. Stojanović, D. Divac, V. Milivojević

Open software architecture for distributed hydro-meteorological and hydropower data acquisition, simulation and design support

Milivojević, D. Divac, N. Grujović, Z. Dubajić, Z. Simić

HYDRO-INFORMATION SYSTEMS AND MANAGEMENT OF HYDROPOWER RESOURCES IN SERBIA

D. Divac, N. Grujović, N. Milivojević, Z. Stojanović, Z. Simić

Abstract

This paper presents an overview and synthesis of a large number of issues related to the contemporary development of hydro-information systems that are developed in the Institute for Development of Water Resources “Jaroslav Černi” in order to meet the needs of management of the hydropower potential of Serbia. Hydro-information systems are designed to provide support to decision-making processes so they can provide significant information on different processes within a catchment on scenarios of future development with multiple variants, as well as on the system utilization in real-time. The most important goals of the development and application of such systems are the following: integration of all relevant hydrologic, meteorological, hydrogeologic, hydropower and other data, as well as the creation of the conditions for their availability to a wide circle of interested users, making of the best possible decisions related to operational management of hydropower plants in various situations, as well as making of the best possible strategic decisions in order to make the optimum choice of the solution for the integral basin management. This paper is based on such a concept so that the original contributions related to the subject topic are presented within a broader framework. At the beginning are presented certain general considerations related to planning and management of water resources, as well as the general role of hydropower plants within an integral electricity generation and transmission system. Further on, the reader is introduced to the application of information technologies in exploitation of water resources, with a particular stress on the role of simulation and optimization software in the management of hydropower systems. After this overview that describes broadly, but precisely, the main notions, the paper presents the role and importance of hydropower plants within the electricity generation and transmission system of Serbia, including a short overview of the possible further development of electricity generation capacities. The central part of the paper presents the concepts and structures of hydroinformation systems (which consist of the following sub-systems: central server, acquisition servers and user sub-systems, which include the user server and specialized HIS applications). Three main hydro-information systems in Serbia are specifically outlined and described in detail; they are being continuously developed in all aspects in accordance with the presented concepts and structures. These systems are: “Iron Gate” Hydro-Information System  (related to the system of hydropower plants built on the common Serbian-Romanian section of River Danube; Serbian and Romanian hydropower plant “Iron Gate 1”, with the total installed discharge of 9800 m3/s and the total installed power of 2165 MW, and Serbian and Romanian hydropower plant “Iron Gate 2”, with the total installed discharge of 8500 m3/s and total installed power of 540 MW), “Drina” Hydro-Information System (which relates to the whole river Drina basin with an area of 19570 km2, which is shared between the three neighboring states, so that 30.5% of its area belongs to Serbia, 31.5% to Montenegro, and 37% to Bosniaand-Herzegovina; the system of 9 hydropower plants was built in the River Drina catchment and these plants have the total installed power of 1932 MW and average annual electricity generation of 6350 GWh; in this catchment it is possible to develop significant new hydropower capacities, which would allow for additional annual electricity generation higher than  7000 GWh), and “Vlasina” Hydro-Information System (which is related to the system of “Vlasinske HPPs” that has a relatively low power of 125.9 MW and the mean annual electricity generation of 295 GWH, but which represents a very important electricity generation plant within the system of EPS (Electric Power Industry of Serbia), because it is used for generation of peak-load electricity and as the cold or spinning reserve of the system). The presented hydroinformation systems are actually the systems for the support to decision-making on all levels, i.e., local, regional, state and trans-boundary. These systems create possibilities for the optimum management in real time as well as harmonization of various interested parties (electric power industries, situated in different states, with different interests that operate under the circumstances of the evident lack of uniformity regarding natural inflows and consumption needs). In a long run the conditions are created for the further development on the catchment (new development projects, additional generation capacities etc.) in order to achieve the optimum exploitation of hydropower potential, as well as the multi-purpose use of water.

SWAT-BASED RUNOFF MODELING IN COMPLEX CATCHMENT AREAS – THEORETICAL BACKGROUND AND NUMERICAL PROCEDURES

Simić, N. Milivojević, D. Prodanović, V. Milivojević, N. Perović

Abstract

This paper shows the structure of the SWAT-based model used in modeling of the “rainfallrunoff” process. The SWAT model is hydro-dynamic and physically-based model for application in complex and large basins. Model inputs are as follows: rainfall, air temperature, soil characteristics, topography, vegetation, hydrogeology and other relevant physical parameters. The model is based on five linear reservoirs as follows: reservoir of the vegetation cover, snow accumulation and melting, surface reservoir, underground reservoir and surface runoff reservoir. The model uses GIS tools for preprocessing and post-processing. The basic modeling unit is the hydrologic response unit (HRU), defined as the network of elementary hydrologic areas with the selected discretization, measure of which is dependent upon the desired accuracy, as well as upon data accuracy. The total runoff on the exit profile of the catchment is computed by convolution of the sum of runoffs (surface and base runoffs). The model can be applied at the daily and hourly level of discretization and used for multiannual simulations. Illustration of operation of the SWAT based model will be presented on a selected part of the River Drina basin (with the total area of around 20.000 km2).

HYDRO-METEOROLOGICAL DATA QUALITY ASSURANCE AND IMPROVEMENT

N. Branisavljević, D. Prodanović, M. Arsić, Z. Simić, J. Borota

Abstract

Advances in measurement equipment and data transfer enabled easy and economic automatic monitoring of various hydro-meteorological variables. The main characteristic of such automatic monitoring systems is that they do not rely on human activities, but only on electronic devices. Even if those electronic devices are of highest quality and accuracy, and properly tuned to specific problem, the reliability of measured values relyieson many other factors and unexpected or undesired occurrences, like modification of measurement microlocation, power supply shortages or surges, etc. The sampled and acquired data values have to be additionally checked, validated and sometimes improved or cleared before further use. This paper presents an innovative approach to data validation and improvement through the framework generally applicable to all hydrological data acquisition systems. The proposed framework can incorporate any number of validation methods and can be easily customized according to the characteristics of every single measured variable. The framework allows for the self-adjustment and feedback to support self-learning of used validation methods, same as expert-controlled learning and supervision. After data validation, for low-scored data, its value quality can be improved if redundant data exist, so framework has the data reconstruction module. By applying different interpolation techniques or using redundant data value the new data is created same as accompanying metadata with the reconstruction history. After data reconstruction, the framework supports the data adjustment, the post-processing phase where the data is adjusted for the specific needs of each user. Every validated and sometimes improved data value is accompanied with a meta-data that holds its validation grade as a quality indicator for further use.

DISCRETE EVENTS SIMULATION MODEL APPLIED TO LARGE-SCALE HYDRO-SYSTEMS

Milivojević, N. Grujović, B. Stojanović, D. Divac, V. Milivojević

Abstract

This paper presents the principles of simulation model developed with DEVS formalism for large-scale hydro-systems management and planning. This simulation model, being DEVSbased, is natively object-oriented, open for communication with other models and is suitable for parallel execution in multiprocessor and distributed environments. It is designed as a part of the hydro-information system, whose strategic objective is to create environment for the optimum management of water resources and to address and resolve the existing and potential conflicts of interest in the region, related to multi-purpose use of water, and the misalignment of interests of the various stakeholders in the river basin. The functional objective of the simulation model is to support water management decision-making (i.e. to aid users in the assessment of the consequences of various management scenarios and to support planning within various hydrologic, climatic, economic, regulatory and political constraints). The combined use of the rainfall/runoff model and DEVS-based simulation for system elements represents a new approach when it comes to water and hydropower management. The model and simulation core make a solid base for the application of optimization algorithms, in order to provide more automated decision support system. A case study of River Drina Basin simulation model, named “Drina” Hydro-Information System is also presented.

Open software architecture for distributed hydro-meteorological and hydropower data acquisition, simulation and design support

Milivojević, D. Divac, N. Grujović, Z. Dubajić, Z. Simić

Abstract

In order to provide support to management of complex hydropower systems and their digital simulations it is necessary to establish communication between measurement systems and computational models, although they were not primarily designed on the concepts of mutual integration and possible reusability. This paper presents one of the possible solutions for distributed hydro-meteorological and hydropower data acquisition, simulation and design support that is based on service-oriented architecture (SOA) principles. The complex and heterogeneous information flow used by these systems is portioned into separate data and computational functions that use common open protocols for mutual communication. Based on the Web Services techniques, the paper presents the principals that can help design many business-independent services and deploy them depending on computational power and data distribution. The Web Services technology can not only reduce the complexity of applied software and improve its reusability, but it can also implement dynamic application integration in order to decrease the costs of system development and maintenance.