Journal articles: 'Hydraulic system validation'

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Noh, D. K., J. S. Jang, J. H. Seo, H. S. Kim, and S. H. Park. "Development of Drifter's Hydraulic System Model and Its Validation." Journal of The Korean Society for Fluid Power & Construction Equipments 11, no. 3 (September 1, 2014): 14–21. http://dx.doi.org/10.7839/ksfc.2014.11.3.014.

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HATTORI, Tomoya, Noboru KAWAGUCHI, Yutaka EZAKI, Junji TAKAKI, Masao SAITO, Masahiro SUGIMOTO, Satoshi SATOH, and Katsuhiko YAMADA. "Experimental validation of hydraulic support system for large structures." Transactions of the JSME (in Japanese) 87, no. 900 (2021): 21–00060. http://dx.doi.org/10.1299/transjsme.21-00060.

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Ketelsen, Søren, Sebastian Michel, Torben O. Andersen, Morten Kjeld Ebbesen, Jürgen Weber, and Lasse Schmidt. "Thermo-Hydraulic Modelling and Experimental Validation of an Electro-Hydraulic Compact Drive." Energies 14, no. 9 (April 22, 2021): 2375. http://dx.doi.org/10.3390/en14092375.

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Electro-hydraulic compact drives (ECDs) are an emerging technology for linear actuation in a wide range of applications. Especially within the low power range of 5–10 kW, the plug-and-play capability, good energy efficiency and small space requirements of ECDs render this technology a promising alternative to replace conventional valve-controlled linear drive solutions. In this power range, ECDs generally rely on passive cooling to keep oil and system temperatures within the tolerated range. When expanding the application range to larger power classes, passive cooling may not be sufficient. Research investigating the thermal behaviour of ECDs is limited but indeed required for a successful expansion of the application range. In order to obtain valuable insights into the thermal behaviour of ECDs, thermo-hydraulic simulation is an important tool. This may enable system design engineers to simulate thermal behaviour and thus develop proper thermal designs during the early design phase, especially if such models contain few parameters that can be determined with limited information available. Our paper presents a lumped thermo-hydraulic model derived from the conservation of mass and energy. The derived model was experimentally validated based on experimental data from an ECD prototype. Results show good accuracy between measured and simulated temperatures. Even a simple thermal model containing only a few thermal resistances may be sufficient to predict steady-state and transient temperatures with reasonable accuracy. The presented model may be used for further investigations into the thermal behaviour of ECDs and thus toward proper thermal designs required to expand the application range.

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Osusky, Filip, Stefan Cerba, Jakub Luley, Branislav Vrban, and Jan Hascik. "COUPLED SIMULATION OF GAS COOLED FAST REACTOR FUEL ASSEMBLY WITH NESTLE CODE SYSTEM." Acta Polytechnica CTU Proceedings 14 (May 17, 2018): 34. http://dx.doi.org/10.14311/app.2018.14.0034.

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The paper is focused on coupled calculation of the Gas Cooled Fast Reactor. The proper modelling of coupled neutronics and thermal-hydraulics is the corner stone for future safety assessment of the control and emergency systems. Nowadays, the system and channel thermal-hydraulic codes are accepted by the national regulatory authorities in European Union for license purposes, therefore the code NESTLE was used for the simulation. The NESTLE code is a coupled multigroup neutron diffusion code with thermal-hydraulic sub-channel code. In the paper, the validation of NESTLE code 5.2.1 installation is presented. The processing of fuel assembly homogeneous parametric cross-section library for NESTLE code simulation is made by the sequence TRITON of SCALE code package system. The simulated case in the NESTLE code is one fuel assembly of GFR2400 concept with reflective boundary condition in radial direction and zero flux boundary condition in axial direction. The results of coupled calculation are presented and are consistent with the GFR2400 study of the GoFastR project.

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Wiens, Travis, and Brendan Deibert. "A Low-Cost Miniature Electrohydrostatic Actuator System." Actuators 9, no. 4 (December 4, 2020): 130. http://dx.doi.org/10.3390/act9040130.

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Hydraulic linear actuators dominate in high power applications but are much less common in low power (<100 W) systems. One reason for this is the cost: electric actuators in this power range generally exhibit lower performance but are also much less expensive than hydraulic systems. However, in recent years, some miniature hydraulic components have been mass produced, driving down prices. This paper presents the application of these low-cost components, together with a novel very low-cost 3D-printed valve to create an electrohydrostatic actuator. Capable of very high power and force density, this system is competitive on cost with lower-performing electric actuators. This paper presents models for the system’s performance, as well as experimental validation data.

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Xu, Ming, and Hui Yuan Li. "Research on Constant Torque Control System Design for Hydraulic Retarder of Heavy Vehicle." Advanced Materials Research 538-541 (June 2012): 2493–99. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.2493.

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The analysis of inner circulation circle flow characteristic of the partly filled hydraulic retarder during its braking course is carried out. a relation between the liquid filled ratio of the circulation circle in hydraulic retarder， the inner flow field pressure characteristic and the output torque characteristic of it is established, The control parameter token for the hydraulic retarder torque characteristic is acquired, then the Constant Torque Control System for Heavy Vehicle Hydraulic Retarder is formed. Through a test bed experiment of Constant Torque Control System for Heavy Vehicle Hydraulic Retarder, the validation of the Constant Torque Control System for Heavy Vehicle Hydraulic Retarder is verified，the whole system perfectly meet the design request.

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Wolfert, K., and I. Brittain. "CSNI validation matrix for PWR and BWR thermal-hydraulic system codes." Nuclear Engineering and Design 108, no. 1-2 (June 1988): 107–19. http://dx.doi.org/10.1016/0029-5493(88)90060-x.

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Takalo, Ville, Salvador Esque, Jouni Mattila, Matti Vilenius, Jorma Järvenpää, Mikko Siuko, Luigi Semeraro, Mike Irving, and Carlo Damiani. "Validation of Divertor Cassette locking system with a hydraulic jack tool." Fusion Engineering and Design 84, no. 7-11 (June 2009): 1808–12. http://dx.doi.org/10.1016/j.fusengdes.2008.11.039.

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Van Blaricum, Vicki L., and Vincent F. Hock. "Water Distribution System Modeling and Remote Monitoring." Advanced Materials Research 38 (March 2008): 132–42. http://dx.doi.org/10.4028/www.scientific.net/amr.38.132.

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Localized internal corrosion of water distribution piping is difficult to detect, diagnose, and mitigate. This paper describes the demonstration and validation of multi-parameter water quality sensors and corrosion rate sensors that were permanently installed at a U. S. Army installation to detect corrosion problems and fine-tune the chemical treatment program. This paper will include results of the sensor demonstration and validation. Follow-on work includes the integration of the sensors with a dynamic real-time water distribution system chemical and hydraulic simulation. This work will also be described.

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Du, Heng, Qingming Zhang, Shumei Chen, and Jinhui Fang. "Modeling, simulation, and experimental validation of electro-hydraulic power steering system in multi-axle vehicles." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 233, no. 2 (December 19, 2017): 317–32. http://dx.doi.org/10.1177/0954407017743346.

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An accurate electro-hydraulic power steering system (EHPSS) model is essential to analyze dynamic steering performance and advanced nonlinear control. The main obstacle to establish an accurate model is the complex structure, including steering mechanism, valve controlled dual hydraulic-actuator, and heavy duty tires. This paper constructs a suitable model incorporating these parts, based on a Lagrange equation describing the steering trapezoid mechanism and dual cylinder hydraulic dynamics, regarding steering resisting moment as an external load. A simplified tire model is used to represent the tire basic steering load characteristics. Due to the complexity of the kinematic relationship in the model, several expressions are fitted using back propagation neural networks to significantly reduce calculation difficulty. Experimental measurements and simulation using Matlab/Simulink and experiment are realized for the case of in situ steering, and the results validate the proposed model accuracy. Thus, the proposed model is suitable to analyze the system and design advanced controllers.

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Loi, Nguyen Kim, Nguyen Duy Liem, Le Hoang Tu, Nguyen Thi Hong, Cao Duy Truong, Vo Ngoc Quynh Tram, Tran Thong Nhat, Tran Ngoc Anh, and Jaehak Jeong. "Automated procedure of real-time flood forecasting in Vu Gia – Thu Bon river basin, Vietnam by integrating SWAT and HEC-RAS models." Journal of Water and Climate Change 10, no. 3 (August 24, 2018): 535–45. http://dx.doi.org/10.2166/wcc.2018.015.

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Abstract The precise and reliable simulation of hydrologic and hydraulic processes is important for efficient flood forecasting and warning. The study proposes a real-time flood forecasting system which integrates a coupled hydrological-hydraulic modeling system, weather station network, and stream gauges in a web-based visualization environment. An automated procedure was developed for linking dynamically terrestrial rainfall-runoff processes and river hydraulics by coupling the SWAT hydrological model and the HEC-RAS hydraulic model. The flood forecasting system was trialed in the Vu Gia – Thu Bon river basin, Quang Nam province, Vietnam. The results showed good statistical correlation between predicted and measured stream flow for a 10-year calibration period (R² = 0.95, NSI = 0.95, PBIAS = −1.54) and during the following 10-year validation period as well (R² = 0.93, NSI = 0.93, PBIAS = 6.18). A close-up analysis of individual storm events indicated that the magnitude and timing of peak floods were accurately predicted in 2015 (R² = 0.88, NSI = 0.69, PBIAS = 4.50) and 2016 (R² = 0.80, NSI = 0.93, PBIAS = 6.18). In addition, the automated procedure was demonstrated to be reliable with dependable computational efficiency of less than 5 minutes' processing time.

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Hou, Zhi Jian, Ming Qu, and Zhi Rui Wang. "Flow Resistance Coefficient Identification of Chilled Water System Based on Multi-Objective Optimization and Experiment Validation." Applied Mechanics and Materials 651-653 (September 2014): 742–46. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.742.

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Hydraulic resistance coefficient (HRC) is a fundamental parameter that characterizes the hydraulic state of a water pipeline and significantly determines the efficiency of the water-transport process. To estimate HRC and diagnose hydraulic process fault in building air conditioning system, a novel method called multi-objective optimization (MBO) strategy was developed in the research effort. MBO is concerned with mathematical optimization problems involving more than one objective function to be optimized simultaneously. In this paper, first, the basic principle of the approach is presented. Then several experiments are conducted to identify the HRC in a real air conditioning system. And the water flow rate of each air handling terminal unit is estimated by the flow rate of primary pipe and identified HRC. The experiment results show that the model can accurately estimate HRCs. The HRCs of each pipe and terminal unit were obtained by the flow rate and the pressure difference of primary pipe without requiring geometric specifications, which is very convenient in real engineering application.

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Szabo-Meszaros, Marcell, Ana Silva, Kim Bærum, Henrik Baktoft, Knut Alfredsen, Richard Hedger, Finn Økland, et al. "Validation of a Swimming Direction Model for the Downstream Migration of Atlantic Salmon Smolts." Water 13, no. 9 (April 28, 2021): 1230. http://dx.doi.org/10.3390/w13091230.

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Fish swimming performance is strongly influenced by flow hydrodynamics, but little is known about the relation between fine-scale fish movements and hydrodynamics based on in-situ investigations. In the presented study, we validated the etho-hydraulic fish swimming direction model presented in the River Mandal from Southern Norway, using similar behavioral and hydraulic data on salmon smolts from the River Orkla in Central Norway. The re-parametrized model explained the variation of the swimming direction of fish in the Orkla system in same degree as the original model performed in the Mandal system (R2: 84% in both cases). The transferability of the model when using it from one river to predict swimming direction in the other river was lower (R2: 21% and 26%), but nevertheless relatively high given that the two localities differed in hydraulic conditions. The analyses thus provide support for the fact that the identified hydraulic parameters and their interaction affected smolt behavior in a similar way at the two sites, but that local parametrization of the base model is required. The developed etho-hydraulic models can provide important insights into fish behavior and fish migration trajectories and can be developed into prediction models important for the future development of behavioral downstream migration solutions.

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Branson, D. T., P. S. Keogh, and D. G. Tilley. "The hydraulic actuation of multi-body structures through large scale motions. Part 1: Development and validation of system model." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 222, no. 2 (February 1, 2008): 181–93. http://dx.doi.org/10.1243/09544062jmes530.

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Modern engineering design is leading towards structures that are complex and lightweight. These structures often contain flexible and rigid components actuated through large displacements by a non-linear hydraulic system. Due to the increased system complexities, there is a need to define structural models that can be easily coupled to models of the hydraulic system for use in the design of suitable controllers. The current paper develops a modular system model composed of rigid and flexible structural components coupled directly to a non-linear hydraulic system. The resulting model allows for changes to be made to the hydraulic and structural components in an independent manner such that the entire system may be incorporated in a single simulation domain. A structural damping matrix is introduced that allows a control system designer to assign realistic modal damping ratios to well established modes, and higher damping to modes with significant uncertainty. This allows for increased steady-state accuracy and model run-time efficiency, which is beneficial to the controller design process presented in Part 2. The system modelling approach is applied to a hydraulically actuated experimental rig for validation purposes.

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Ramdani, Sulaeman Deni, Angga Pangestu, and Haris Abizar. "The dual-design-based pneumatic simulator as supporting media for electro-pneumatic practicum in vocational higher education." Jurnal Pendidikan Vokasi 9, no. 3 (February 5, 2020): 307. http://dx.doi.org/10.21831/jpv.v9i3.27345.

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This study aims to: (1) determine the process of developing a learning media simulator for electro-pneumatic systems based on dual design, (2) knowing the effectiveness of learning media in the form of electro-pneumatic system simulators based on dual design. This research is a research and development adapted from the 4D development model, namely Define, Design, Develop and Disseminate. The subjects of this study were students of Mechanical Engineering Education in Semester IV and V with 30 students taking pneumatic hydraulic courses. Data collection techniques in this study used questionnaires and interviews with research instruments in the form of interview guidelines and questionnaires. The data obtained were analyzed with descriptive quantitative. The results showed (1) The results of the development of learning media for electro-pneumatic system simulators based on Dual Design as supporting media for electro-pneumatic practices produced 3 main components, namely the working system in the pneumatic electro system, wiring diagrams and electrical circuits, (2) the feasibility results of expert validation media is 84% (Very Good), expert material validation is 92% (Very Good), and user validation is 86% (Very Good). So, the learning media for electro-pneumatic system simulator is feasible as a learning media in pneumatic hydraulic courses.

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Ding, Yu, Fei Wang, Zhen-ya Wang, and Wen-jin Zhang. "Fault Diagnosis for Hydraulic Servo System Using Compressed Random Subspace Based ReliefF." Complexity 2018 (2018): 1–14. http://dx.doi.org/10.1155/2018/8740989.

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Playing an important role in electromechanical systems, hydraulic servo system is crucial to mechanical systems like engineering machinery, metallurgical machinery, ships, and other equipment. Fault diagnosis based on monitoring and sensory signals plays an important role in avoiding catastrophic accidents and enormous economic losses. This study presents a fault diagnosis scheme for hydraulic servo system using compressed random subspace based ReliefF (CRSR) method. From the point of view of feature selection, the scheme utilizes CRSR method to determine the most stable feature combination that contains the most adequate information simultaneously. Based on the feature selection structure of ReliefF, CRSR employs feature integration rules in the compressed domain. Meanwhile, CRSR substitutes information entropy and fuzzy membership for traditional distance measurement index. The proposed CRSR method is able to enhance the robustness of the feature information against interference while selecting the feature combination with balanced information expressing ability. To demonstrate the effectiveness of the proposed CRSR method, a hydraulic servo system joint simulation model is constructed by HyPneu and Simulink, and three fault modes are injected to generate the validation data.

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Maghareh, Amin, Christian E. Silva, and Shirley J. Dyke. "Parametric model of servo-hydraulic actuator coupled with a nonlinear system: Experimental validation." Mechanical Systems and Signal Processing 104 (May 2018): 663–72. http://dx.doi.org/10.1016/j.ymssp.2017.11.009.

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Stubkier, Soeren, Henrik C. Pedersen, and Torben O. Andersen. "Design and Experimental Validation of Hydraulic Yaw System for Multi MW Wind Turbine." International Journal of Fluid Power 14, no. 2 (January 2013): 27–38. http://dx.doi.org/10.1080/14399776.2013.10781073.

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Martins, Ricardo, Jorge Leandro, and Rita Fernandes de Carvalho. "Characterization of the hydraulic performance of a gully under drainage conditions." Water Science and Technology 69, no. 12 (March 31, 2014): 2423–30. http://dx.doi.org/10.2166/wst.2014.168.

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During rainfall events with low return periods (1–20 years) the drainage system can provide some degree of protection to urban areas. The system design is based not only on good hydraulic performance of the surface and the sewer network but also on their linking elements. Although the linking elements are of utmost importance as they allow the exchange of flow between the surface and the sewer network, there is a lack of studies that thoroughly characterize them. One crucial structural part of those elements is the gully. State-of-the-art dual-drainage models often use simplified formulae to replicate the gully hydraulic behaviour that lacks proper validation. This work focuses on simulating, both numerically and experimentally, the hydraulic performance of a 0.6 × 0.3 × 0.3 [m] (L × W × D) gully located inside an 8 × 0.5 × 0.5 [m] rectangular channel. The numerical simulations are conducted with the OpenFOAM toolbox and validated with water level measurements in the Multiple-Linking-Element experimental installation located at the Laboratory of Hydraulics of the University of Coimbra. The results provide a complete three-dimensional insight of the hydraulic behaviour of the flow inside the gully, and discharge coefficient formulae are disclosed that can be directly applied in dual-drainage models as internal boundary conditions.

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Romero, Guillermo, Vicente S. Fuertes-Miquel, Óscar E. Coronado-Hernández, Román Ponz-Carcelén, and Francisco Biel-Sanchis. "Transient Phenomena Generated in Emptying Operations in Large-Scale Hydraulic Pipelines." Water 12, no. 8 (August 18, 2020): 2313. http://dx.doi.org/10.3390/w12082313.

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Air pockets generated during emptying operations in pressurized hydraulic systems cause significant pressure drops inside pipes. To avoid these sudden pressure changes, one of the most widely used methods involves the installation of air valves along the pipeline route. These elements allow air exchange between the exterior and the interior of the pipe, which alleviates the pressure drops produced and thus prevents possible breaks or failures in the structure of the installation. This study uses a mathematical model previously validated by the authors in smaller installations to simulate all hydraulic variables involved in emptying processes over time. The purpose of these simulations is the validation of the mathematical model in real large-scale installations, and to do this, the results obtained with the mathematical model are compared with actual measurements made by the partner company. The hydraulic system selected for the study is a pipeline with a nominal diameter of 400 mm and a total length of 1020 m. The results obtained from the mathematical model show great similarity with the experimental measurements, thus validating the model for emptying large pipes.

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Dawei, Pi, Kong Zhenxing, Wang Xianhui, Wang Hongliang, and Chen Shan. "Design and experimental validation of control algorithm for vehicle hydraulic active stabilizer bar system." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 233, no. 5 (May 14, 2018): 1280–95. http://dx.doi.org/10.1177/0954407018770539.

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This paper presents a novel active roll control algorithm for vehicle hydraulic active stabilizer bar system. The mechanical structure and control scheme of hydraulic active stabilizer bar system is detailed. The anti-roll torque controller is designed with “Proportional-Integral-Differential (PID) + feedforward” algorithm to calculate the total anti-roll torque. A lateral acceleration gain and roll rate damping are added into “PID + feedforward” controller, which can improve vehicle roll dynamic response. The torque distributor is introduced based on fuzzy–PID algorithm to distribute the anti-roll torque of front and rear stabilizer bar dynamically, which can improve vehicle yaw dynamics response. The actuator controller is used for realizing the closed-loop control of the actuators displacement and generating the accurate anti-roll torque. The hardware-in-the-loop simulation platform is established based on AutoBox and active stabilizer bar actuators. The hardware-in-the-loop experiment is carried out under typical maneuvers. Experimental results show that the proposed control algorithm improves the vehicle roll and yaw dynamics response, which can enhance the vehicle roll stability, yaw stability, and ride comfort.

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Ragavan, S. Veera, Jeya Mithra Kumar, and S. G. Ponnambalam. "Design of a Mechatronic Drive Train with Regenerative Braking." Applied Mechanics and Materials 110-116 (October 2011): 5111–17. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.5111.

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Building a research framework for a Parallel Hydraulic Hybrid (PHH) Prototype with Hydraulic Regenerative Braking and Launch Assist (HRB/HLA) System for small and medium sized vehicles has been attempted. The objective of this work is to capture lost Kinetic Energy during braking and store that captured energy in a pressurized accumulator to be used again to assist accleration. The experimental implementation and validation of the Regenerative Braking System concept for light vehicles has been done using a go-kart powered by a single cylinder Honda engine to demonstrate energy savings in a real life braking scenario. A light weight test system accommodating all the Hydraulic Breaking System components mounted at the rear of the go-kart has been successfully built and tested.

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Sánchez, V. H., M. Thieme, and W. Tietsch. "Validation and Application of the Thermal Hydraulic System Code TRACE for Analysis of BWR Transients." Science and Technology of Nuclear Installations 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/247482.

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The Karlsruhe Institute of Technology (KIT) is participating on (Code Applications and Maintenance Program) CAMP of the US Nuclear Regulatory Commission (NRC) to validate TRACE code for LWR transient analysis. The application of TRACE for the safety assessment of BWR requires a throughout verification and validation using experimental data from separate effect and integral tests but also using plant data. The validation process is normally focused on safety-relevant phenomena for example, pressure drop, void fraction, heat transfer, and critical power models. The purpose of this paper is to validate selected BWR-relevant TRACE-models using both data of bundle tests such as the (Boiling Water Reactor Full-Size Fine-Mesh Bundle Test) BFBT and plant data recorded during a turbine trip event (TUSA) occurred in a Type-72 German BWR plant. For the validation, TRACE models of the BFBT bundle and of the BWR plant were developed. The performed investigations have shown that the TRACE code is appropriate to describe main BWR-safety-relevant phenomena (pressure drop, void fraction, and critical power) with acceptable accuracy. The comparison of the predicted global BWR plant parameters for the TUSA event with the measured plant data indicates that the code predictions are following the main trends of the measured parameters such as dome pressure and reactor power.

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Ren, Yan, Jiping Bai, and Jian Ruan. "Design, Modeling and Experimental Validation of a Variable Resonant Electro-Hydraulic Fatigue Testing System." IEEE Access 7 (2019): 180835–45. http://dx.doi.org/10.1109/access.2019.2957126.

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Xu, Beibei, Diyi Chen, Silvia Tolo, Edoardo Patelli, and Yanlong Jiang. "Model validation and stochastic stability of a hydro-turbine governing system under hydraulic excitations." International Journal of Electrical Power & Energy Systems 95 (February 2018): 156–65. http://dx.doi.org/10.1016/j.ijepes.2017.08.008.

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Kozmenkov, Y., S. Kliem, and U. Rohde. "Validation and verification of the coupled neutron kinetic/thermal hydraulic system code DYN3D/ATHLET." Annals of Nuclear Energy 84 (October 2015): 153–65. http://dx.doi.org/10.1016/j.anucene.2014.12.012.

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Klapcsik, Kálmán, Roxána Varga, and Csaba Hős. "Optimal Pressure Measurement Layout Design in Water Distribution Network Systems." Periodica Polytechnica Mechanical Engineering 62, no. 1 (November 13, 2017): 51. http://dx.doi.org/10.3311/ppme.11409.

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This paper addresses the problem of locating the optimal pressure measurement points in a hydraulic system to help system management, calibration/validation of hydraulic models and measurement planning. Two approaches are discussed in the present work. The first method splits the hydraulic system by means of community concept borrowed from graph theory and uses merely the topology of the network. The resulting subsystems will have minimum number of external and maximum number of internal connections and leaves the choice of locating the single pressure measurement location per subsystem to a higher-level decision. The second technique is based on the sensitivity analysis of the hydraulic network and places the measurement points at the most sensitive locations, while trying to preserve the spatial diversity of the layout, i.e. preventing the accumulation of the measurement points within a small area of high sensitivity. The performance of both techniques is demonstrated on real-size hydraulic networks. The proposed sampling layouts are compared to classic D-optimality, A-optimality and V-optimality criterion.

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Quintana Seguí, P., E. Martin, F. Habets, and J. Noilhan. "Improvement, calibration and validation of a distributed hydrological model over France." Hydrology and Earth System Sciences 13, no. 2 (February 18, 2009): 163–81. http://dx.doi.org/10.5194/hess-13-163-2009.

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Abstract. The hydrometeorological model SAFRAN-ISBA-MODCOU (SIM) computes water and energy budgets on the land surface and riverflows and the level of several aquifers at the scale of France. SIM is composed of a meteorological analysis system (SAFRAN), a land surface model (ISBA), and a hydrogeological model (MODCOU). In this study, an exponential profile of hydraulic conductivity at saturation is introduced to the model and its impact analysed. It is also studied how calibration modifies the performance of the model. A very simple method of calibration is implemented and applied to the parameters of hydraulic conductivity and subgrid runoff. The study shows that a better description of the hydraulic conductivity of the soil is important to simulate more realistic discharges. It also shows that the calibrated model is more robust than the original SIM. In fact, the calibration mainly affects the processes related to the dynamics of the flow (drainage and runoff), and the rest of relevant processes (like evaporation) remain stable. It is also proven that it is only worth introducing the new empirical parameterization of hydraulic conductivity if it is accompanied by a calibration of its parameters, otherwise the simulations can be degraded. In conclusion, it is shown that the new parameterization is necessary to obtain good simulations. Calibration is a tool that must be used to improve the performance of distributed models like SIM that have some empirical parameters.

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Quintana Seguí, P., E. Martin, F. Habets, and J. Noilhan. "Improvement, calibration and validation of a distributed hydrological model over France." Hydrology and Earth System Sciences Discussions 5, no. 3 (June 11, 2008): 1319–70. http://dx.doi.org/10.5194/hessd-5-1319-2008.

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Abstract. The hydrometeorological model SAFRAN-ISBA-MODCOU (SIM) computes water and energy budgets on the land surface and riverflows and the level of several aquifers at the scale of France. SIM is composed of a meteorological analysis system (SAFRAN), a land surface model (ISBA) and a hydrogeological model (MODCOU). In this study, an exponential profile of hydraulic conductivity at saturation is introduced to the model and its impact analysed. It is also studied how calibration modifies the performance of the model. A very simple method of calibration is implemented and applied to the parameters of hydraulic conductivity and subgrid runoff. The study shows that a better description of the hydraulic conductivity of the soil is important to simulate more realistic discharges. It is also shown that the calibrated model is more robust than the original SIM. In fact, the calibration mainly affects the processes related to the dynamics of the flow (drainage and runoff), and the rest of relevant processes (like evaporation) remain stable. It is also proven that it is only worth introducing the new empirical parameterization of hydraulic conductivity if it is accompanied by a calibration of its parameters, otherwise the simulations can be degraded. In conclusion, it is shown that the new parameterization is necessary to obtain good simulations. Calibration is a tool that must be used to improve the performance of distributed models like SIM that have some empirical parameters.

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Petruzzi, Alessandro, and Francesco D'Auria. "Thermal-Hydraulic System Codes in Nulcear Reactor Safety and Qualification Procedures." Science and Technology of Nuclear Installations 2008 (2008): 1–16. http://dx.doi.org/10.1155/2008/460795.

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In the last four decades, large efforts have been undertaken to provide reliable thermal-hydraulic system codes for the analyses of transients and accidents in nuclear power plants. Whereas the first system codes, developed at the beginning of the 1970s, utilized the homogenous equilibrium model with three balance equations to describe the two-phase flow, nowadays the more advanced system codes are based on the so-called “two-fluid model” with separation of the water and vapor phases, resulting in systems with at least six balance equations. The wide experimental campaign, constituted by the integral and separate effect tests, conducted under the umbrella of the OECD/CSNI was at the basis of the development and validation of the thermal-hydraulic system codes by which they have reached the present high degree of maturity. However, notwithstanding the huge amounts of financial and human resources invested, the results predicted by the code are still affected by errors whose origins can be attributed to several reasons as model deficiencies, approximations in the numerical solution, nodalization effects, and imperfect knowledge of boundary and initial conditions. In this context, the existence of qualified procedures for a consistent application of qualified thermal-hydraulic system code is necessary and implies the drawing up of specific criteria through which the code-user, the nodalization, and finally the transient results are qualified.

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Tota, Antonio, Enrico Galvagno, Mauro Velardocchia, and Alessandro Vigliani. "Passenger car active braking system: Model and experimental validation (Part I)." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 232, no. 4 (January 6, 2017): 585–94. http://dx.doi.org/10.1177/0954406216686388.

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This paper introduces a method to characterize the dynamic behavior of a normal production hydraulic brake system through experiments on a hardware-in-the-loop test bench for both modeling (part I) and control (part II) tasks. The activity is relative to the analysis, modeling, and control of anti-lock braking system and electronic stability control digital valves, and is aimed at obtaining reference tracking and disturbance-rejection performance similar to that achievable when using pressure proportional valves. The first part of this two-part study is focused on the development of a mathematical model that emulates the pressure dynamics inside a brake caliper when the inlet valve, outlet valve, and motor pump are controlled by digital or pulse width modulated signals. The model takes into account some inherent nonlinearities of these systems, e.g. the variation of fluid bulk modulus with pressure, while inlet and outlet valves together with the relay box are modeled as second-order systems with variable gains. The hardware-in-the-loop test rig is used for both parameter estimation and model validation; the parameters and model will be used for the control strategy development presented in the second part of this study.

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Mosunova, N. A., V. M. Alipchenkov, N. A. Pribaturin, V. F. Strizhov, E. V. Usov, P. D. Lobanov, D. A. Afremov, A. A. Semchenkov, and I. A. Larin. "Lead coolant modeling in system thermal-hydraulic code HYDRA-IBRAE/LM and some validation results." Nuclear Engineering and Design 359 (April 2020): 110463. http://dx.doi.org/10.1016/j.nucengdes.2019.110463.

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Thirel, G., E. Martin, J. F. Mahfouf, S. Massart, S. Ricci, and F. Habets. "A past discharges assimilation system for ensemble streamflow forecasts over France – Part 1: Description and validation of the assimilation system." Hydrology and Earth System Sciences 14, no. 8 (August 24, 2010): 1623–37. http://dx.doi.org/10.5194/hess-14-1623-2010.

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Abstract. Two Ensemble Streamflow Prediction Systems (ESPSs) have been set up at Météo-France. They are based on the French SIM distributed hydrometeorological model. A deterministic analysis run of SIM is used to initialize the two ESPSs. In order to obtain a better initial state, a past discharges assimilation system has been implemented into this analysis SIM run, using the Best Linear Unbiased Estimator (BLUE). Its role is to improve the model soil moisture by using streamflow observations in order to better simulate streamflow. The skills of the assimilation system were assessed for a 569-day period on six different configurations, including two different physics schemes of the model (the use of an exponential profile of hydraulic conductivity or not) and, for each one, three different ways of considering the model soil moisture in the BLUE state variables. Respect of the linearity hypothesis of the BLUE was verified by assessing of the impact of iterations of the BLUE. The configuration including the use of the exponential profile of hydraulic conductivity and the combination of the moisture of the two soil layers in the state variable showed a significant improvement of streamflow simulations. It led to a significantly better simulation than the reference one, and the lowest soil moisture corrections. These results were confirmed by the study of the impacts of the past discharge assimilation system on a set of 49 independent stations.

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Thirel, G., E. Martin, J. F. Mahfouf, S. Massart, S. Ricci, and F. Habets. "A past discharges assimilation system for ensemble streamflow forecasts over France – Part 1: Description and validation of the assimilation system." Hydrology and Earth System Sciences Discussions 7, no. 2 (April 22, 2010): 2413–53. http://dx.doi.org/10.5194/hessd-7-2413-2010.

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Abstract. Two Ensemble Streamflow Prediction Systems (ESPSs) have been set up at Météo-France. They are based on the French SIM distributed hydrometeorological model. A deterministic analysis run of SIM is used to initialize the two ESPSs. In order to obtain a better initial state, a past discharges assimilation system has been implemented into this analysis SIM run, using the Best Linear Unbiased Estimator (BLUE). Its role is to improve the model soil moisture by using observed streamflows in order to better simulate streamflow. The skills of the assimilation system were assessed for a 569-day period on six different configurations, including two different physics schemes of the model (the use of an exponential profile of hydraulic conductivity or not) and, for each one, three different ways of considering the model soil moisture in the BLUE state variables. Respect of the linearity hypothesis of the BLUE was verified by assessing of the impact of iterations of the BLUE. The configuration including the use of the exponential profile of hydraulic conductivity and the combination of the moisture of the two soil layers in the state variable showed a significant improvement of streamflow simulations. It led to a significantly better simulation than the reference one, and the lowest soil moisture corrections. These results were confirmed by the study of the impacts of the past discharge assimilation system on a set of 49 independent stations.

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Marcinkowski, Paweł, Adam Kiczko, and Tomasz Okruszko. "Modeling of water flow in multi-channel river system in the Narew National Park." Annals of Warsaw University of Life Sciences – SGGW. Land Reclamation 49, no. 3 (September 1, 2017): 167–77. http://dx.doi.org/10.1515/sggw-2017-0014.

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Abstract Modeling of water flow in multi-channel river system in the Narew National Park. Anastomosing rivers constitute a rare example of multi-channel systems, which used to be very common before the agricultural and industrial development. Presently few of them remain worldwide and the only example in Poland is the Upper River Narew within Narew National Park. Although hydraulic modeling using one-dimensional models is commonly used to describe water flow in rivers, for multi-channel rivers problem is more complicated. For this type of rivers it is expected that the feedback between process of plants growth (expressed by Manning’s coefficient) and distribution of flow in anabranches is high. However, assignment procedure on roughness coefficients in splitting and rejoining channels is laborious and difficult. Therefore, for efficient water flow modeling in multi-channel systems a stand-alone hydraulic model equipped with automatic optimization procedure was developed. Optimization and validation stages, based on field measurements data of discharge and water levels, indicated that the model accurately simulates water flow in multi-channel system.

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Li, Dawei, Mingxing Lin, and Liang Tian. "Design of iron bird for a regional jet aircraft." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 234, no. 3 (October 8, 2019): 681–88. http://dx.doi.org/10.1177/0954410019879822.

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A regional jet’s iron bird was built for trouble shooting and design improvement of its airborne system. Modular design architecture and overall plan for the iron bird were proposed, and structure of the test rig, main tested systems, relevant supporting test systems and test programs were described. Besides, as one of the most critical airborne systems, NLG loading system was chosen for deep research; its mathematical model was built and analyzed in detail. Test results of hydraulic system’s main parameters were given. The whole iron bird provided important guarantee for system testing and continued design improvement. Also, test validation level for multi systems integration and fault diagnosis level of airborne system were improved.

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Li, Ling Jun, and Thomas Thurner. "Modeling and Simulation of Servo-Hydraulic Cylinder Systems for Multi Axis Test Control." Advanced Materials Research 711 (June 2013): 416–21. http://dx.doi.org/10.4028/www.scientific.net/amr.711.416.

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Multi-axial mechanical testing with servo-hydraulic cylinders is used as essential tool within the development and manufacturing process of mechanical components and structures, enabling the experimental validation of the fatigue behavior and related mechanical endurance limits. In this paper we derive the analytical model of servo-hydraulic cylinders feasible for fatigue tests to enable the incorporation of the derived actuator dynamics within multi-axis test control strategies. Our derived cylinder model includes the test cylinder with attached position sensor, and a state-of-the-art servo valve. Based on the obtained cylinder dynamics we propose a simplification to a low order cylinder model, highly desirable for reducing overall system complexity in order to develop ease-of-use controllers of high performance for multi-dimensional test rigs. We compare the simulated output of the derived actuator models with the measured data from a real world test cylinder system. The obtained results show that the obtained system model accurately describes the dynamic properties of a real world test cylinder, and furthermore validates the process of model simplification for efficient control of such cylinders as part of low-bandwidth multi input multi output servo-hydraulic test systems.

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Zhou, Haicheng, Zhaoping Xu, Liang Liu, Dong Liu, and Lingling Zhang. "Design and validation of a novel hydraulic hybrid vehicle with wheel motors." Science Progress 103, no. 1 (September 29, 2019): 003685041987802. http://dx.doi.org/10.1177/0036850419878024.

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With strong demands of energy-saving and environment-friendly vehicles, hydraulic hybrid powertrain is a suitable solution for urban transportation. This article proposes a novel hydraulic hybrid vehicle with wheel motors to improve vehicle power performance and fuel economy. A forward-looking simulation model of the vehicle is built. System parameters are determined according to the power performance demands. A smaller engine is chosen, the peak power of which is reduced by 11.96%. The simulation model is calibrated and verified by experimental tests on the designed test bench. Parameterized simulation results indicate that the acceleration time 0–100 km/h of the designed vehicle is decreased by 36.3% from 19.63 to 12.5 s compared with the conventional vehicle. The maximum vehicle speed is 140 km/h, and the maximum gradeability is 29%. When the engine works in economy mode, fuel consumption is decreased by 35.59% from 15 to 9.66 L per 100 km on the Urban Dynamometer Driving Schedule cycle compared with the conventional vehicle.

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Ding, Haigang, Jiyun Zhao, Gang Cheng, Steve Wright, and Yufeng Yao. "The Influence of Valve-Pump Weight Ratios on the Dynamic Response of Leaking Valve-Pump Parallel Control Hydraulic Systems." Applied Sciences 8, no. 7 (July 22, 2018): 1201. http://dx.doi.org/10.3390/app8071201.

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A new leaking valve-pump parallel control (LVPC) oil hydraulic system is proposed to improve the performance of dynamic response of present variable speed pump control (VSPC) system, which is an oil hydraulic control system with saving energy. In the LVPC, a control valve is operating at leaking status, together with a variable speed pump, to regulate the system flow of hydraulic oil simultaneously. Therefore, the degree of valve control and pump control can be adjusted by regulating the valve-pump weight ratio. The LVPC system design, mathematical model development, system parameter and control performance analysis are carried out systematically followed by an experimental for validation process. Results have shown that after introducing the valve control, the total leakage coefficient increases significantly over a wide range with the operating point and this further increases damping ratios and reduces the velocity stiffness. As the valve-pump weight ratio determines the flow distribution between the valve and the pump and the weight factors of the valve and/or the pump controls determines the response speed of the LVPC system, thus if the weight factors are constrained properly, the LVPC system will eventually have a large synthetic open-loop gain and it will respond faster than the VSPC system. The LVPC will enrich the control schemes of oil hydraulic system and has potential value in application requiring of fast response.

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Guo, Baoling, Amgad Mohamed, Seddik Bacha, Mazen Alamir, Cédric Boudinet, and Julien Pouget. "Reduced-Scale Models of Variable Speed Hydro-Electric Plants for Power Hardware-in-the-Loop Real-Time Simulations." Energies 13, no. 21 (November 3, 2020): 5764. http://dx.doi.org/10.3390/en13215764.

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Variable Speed Hydro-Electric Plant (VS-HEP) equipped with power electronics has been increasingly introduced into the hydraulic context. This paper is targeting a VS-HEP Power Hardware-In-the-Loop (PHIL) real-time simulation system, which is dedicated to different hydraulic operation schemes tests and control laws validation. Then, a proper hydraulic model will be the key factor for building an efficient PHIL real-time simulation system. This work introduces a practical and generalised modelling hydraulic modelling approach, which is based on ‘Hill Charts’ measurements provided by industrial manufacturers. The hydraulic static model is analytically obtained by using mathematical optimization routines. In addition, the nonlinear dynamic model of the guide vane actuator is introduced in order to evaluate the effects of the induced dynamics on the electric control performances. Moreover, the reduced-scale models adapted to different laboratory conditions can be established by applying scaling laws. The suggested modelling approach enables the features of decent accuracy, light computational complexity, high flexibility and wide applications for their implementations on PHIL real-time simulations. Finally, a grid-connected energy conversion chain of bulb hydraulic turbine associated with a permanent magnet synchronous generator is chosen as an example for PHIL design and performance assessment.

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Chen, H. X., Patrick S. K. Chua, and G. H. Lim. "Vibration analysis with lifting scheme and generalized cross validation in fault diagnosis of water hydraulic system." Journal of Sound and Vibration 301, no. 3-5 (April 2007): 458–80. http://dx.doi.org/10.1016/j.jsv.2006.08.041.

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Ferro, L. M. C., L. M. C. Gato, and A. F. O. Falcão. "Design and experimental validation of the inlet guide vane system of a mini hydraulic bulb-turbine." Renewable Energy 35, no. 9 (September 2010): 1920–28. http://dx.doi.org/10.1016/j.renene.2010.01.020.

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Haggag, S., D. Alstrom, S. Cetinkunt, and A. Egelja. "Modeling, Control, and Validation of an Electro-Hydraulic Steer-by-Wire System for Articulated Vehicle Applications." IEEE/ASME Transactions on Mechatronics 10, no. 6 (December 2005): 688–92. http://dx.doi.org/10.1109/tmech.2005.859838.

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Aoyama, Hajime, Kazuyoshi Ishikawa, Junya Seki, Mitsuo Okamura, Saori Ishimura, and Yuichi Satsumi. "Development of Mine Detection Robot System." International Journal of Advanced Robotic Systems 4, no. 2 (June 1, 2007): 25. http://dx.doi.org/10.5772/5693.

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The Mine Detection Robot supports the mine removal work in countries where mines are buried, such as Afghanistan. The development started from September, 2003. Considering running on rough terrains, the robot has four crawlers, and hydraulic motors in front and rear were serially connected by piping so that they could rotate synchronously. Two work arms were mounted on the robot, one was a horizontal multi-joint SCARA type with motorized 2-link arm, while the other was a vertical multi-joint manipulator with 6 degrees of freedom. Also, domestic evaluation tests were carried out from February to March, 2005, followed by overseas validation tests in Croatia from February to March, 2006. These tests were conducted with a mine detecting senor mounted on the Robot, and the detection performance was evaluated by its mine detection rate.

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Lu, Yun Dan, Liang Cai Zeng, Fei Long Zheng, Gang Sheng Kai, and Qiang Hua Xi. "Design and Characteristic Analysis on Servo Amplifier." Advanced Materials Research 926-930 (May 2014): 1235–38. http://dx.doi.org/10.4028/www.scientific.net/amr.926-930.1235.

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With the rapid development of the electro-hydraulic servo control technology, the application of electro-hydraulic servo valve has become more and more widely. Servo amplifier is an important part of the electro-hydraulic servo control system to drive and control servo valve. This essay introduces the principle and the function of servo-amplifier, and designs a servo amplifier with the functions of proportional amplifier, zero adjustment, feedback and current limitation. The performance analysis and validation for the servo amplifier are carried out by using simulation software EDA .On the basis of the simulation, the servo amplifier is fabricated, and its performance is tested. The results indicate that the servo amplifier has features of stable current output, good linearity, rapid response, and fully meet designing requirements.

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Keller, J., and Z. Yuan. "Combined hydraulic and biological modelling and full-scale validation of SBR process." Water Science and Technology 45, no. 6 (March 1, 2002): 219–28. http://dx.doi.org/10.2166/wst.2002.0109.

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The biological reactions during the settling and decant periods of Sequencing Batch Reactors (SBRs) are generally ignored as they are not easily measured or described by modelling approaches. However, important processes are taking place, and in particular when the influent is fed into the bottom of the reactor at the same time (one of the main features of the UniFed process), the inclusion of these stages is crucial for accurate process predictions. Due to the vertical stratification of both liquid and solid components, a one-dimensional hydraulic model is combined with a modified ASM 2d biological model to allow the prediction of settling velocity, sludge concentration, soluble components and biological processes during the non-mixed periods of the SBR. The model is calibrated on a full-scale UniFed SBR system with tracer breakthrough tests, depth profiles of particulate and soluble compounds and measurements of the key components during the mixed aerobic period. This model is then validated against results from an independent experimental period with considerably different operating parameters. In both cases, the model is able to accurately predict the stratification and most of the biological reactions occurring in the sludge blanket and the supernatant during the non-mixed periods. Together with a correct description of the mixed aerobic period, a good prediction of the overall SBR performance can be achieved.

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Salehi, Amin, and Morteza Montazeri-Gh. "Black box modeling of a turboshaft gas turbine engine fuel control unit based on neural NARX." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 233, no. 3 (September 24, 2018): 949–56. http://dx.doi.org/10.1177/1475090218797496.

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Turboshaft gas turbine engine is one of the main components in most marine vehicle propulsion systems. The most important part of the turboshaft engines, which has direct impact on the performance of the engine and, as a result, on the performance of the propulsion system and the vehicle, is the engine fuel control system which requires much attention and precise design. The proper design of the fuel control system requires accurate modeling of the fuel system components, such as fuel control unit. Fuel control unit is an electrohydraulic fuel flow control system, which consists of a pump and control valves, which controls the fuel flow to the combustion chamber based on the electronic control unit command. Because of the physical laws governing the hydraulic systems, fuel control unit exhibits purely nonlinear behavior and also for some behavior caused by hysteresis and friction in valves and internal components of the pump, modeling of the fuel control unit is complicated. Therefore, in this article, black box modeling approach based on neural Nonlinear Autoregressive Model with Exogenous Input (NARX) structure is employed to accurately model the fuel control unit. For this, at first a test bench including hydraulic system, sensors, and data acquisition system are designed and constructed to measure and record data from the fuel control unit inputs and outputs. The training as well as validation data were generated using amplitude-modulated pseudorandom binary signal as an excitation signal. Then, the identified model is evaluated with both validation data and different test data. Results show that the obtained model follows the real system with good accuracy and demonstrate the effectiveness of the NARX structure to model the fuel control unit. This model can be used for fuel controller designing or model-in-the-loop/hardware-in-the-loop simulation/test of controller in future works.

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Yang, Jixiang, Yongming Bian, Meng Yang, Jie Shao, and Ao Liang. "Parameter Matching of Energy Regeneration System for Parallel Hydraulic Hybrid Loader." Energies 14, no. 16 (August 16, 2021): 5014. http://dx.doi.org/10.3390/en14165014.

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Oil shortages and environmental pollution are attracting worldwide attention incrementally. Hybrid falls within one of the effective techniques for those two problems. Taking the loader with high energy consumption and high emission as the target, combined with the hydraulic hybrid technology with high power density and strong energy storage capacity, the parallel hydraulic hybrid loader (PHHL) based on brake energy regeneration is proposed. Firstly, the dynamic models of the key components of the PHHL are established, and the parameters of the part which coincides with the ordinary loader are corrected based on the V-type duty cycle. Then, consid-ering the energy recovery efficiency as well as the characteristics of the loader from the V-type duty cycle, the parameters for several major parts of the energy regeneration system (ERS) were calculated and matched. Then, based on the initial matching, the improved adaptive genetic al-gorithm (AGA) is employed to optimize the control variable of the control strategy and the design parameters of ERS to enhance the economic benefit and performance of the ERS. Furthermore, a simulation validation was conducted. Simulation results show that the ERS with optimized pa-rameters could improve the fuel-saving effect by 25% compared to the ERS with initial parameters, which indicated the rationality of the optimized parameters. Finally, the fuel consumption test of the PHHL prototype under the V-type duty cycle is performed. The results show that the PHHL with the optimization scheme can achieve 9.12% fuel saving, which is on the brink of the potential of brake energy recovery and verifies the feasibility of applying hydraulic hybrid technology on the loader.

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Lai, Qiwei, Liang Liang, Jing Li, Shijing Wu, and Jun Liu. "Modeling and Analysis on Cushion Characteristics of Fast and High-Flow-Rate Hydraulic Cylinder." Mathematical Problems in Engineering 2016 (2016): 1–17. http://dx.doi.org/10.1155/2016/2639480.

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As an indispensable actuator, the hydraulic cylinder has widespread industrial applications in mechanical engineering. The cushion characteristics of hydraulic cylinder directly affect its performance and reliability, especially the one utilized in hydraulic system with fast response, high flow rate, and instantaneous super power. In order to analyze the cushion characteristics, three different simulation models are established. Furthermore, experiments concerning the pressure characteristics of hydraulic cylinder are accomplished to verify the validation of simulation models. It was found that the integrated simulation model had the highest precision and CFD model showed better pattern of cushion process compared with other models. On the basis of the integrated simulation model, plunger structure and key structural parameters were studied in detail with optimal schemes given. The conical structure, proper design of the diameter of cushion hole, and length of plunger turned out to be effective in promoting the cushion performance. The proposed simulation models and research of cushion structure have scientific and engineering value to promote the innovative development of hydraulic cylinder.

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Moelants, N., I. Y. Smets, R. Van Den Broeck, N. Lambert, S. Liers, P. Declerck, L. Vanysacker, and J. F. Van Impe. "Towards a low complexity carbon removal model for the optimal design of compact decentralised wastewater treatment systems." Water Science and Technology 61, no. 6 (March 1, 2010): 1579–88. http://dx.doi.org/10.2166/wst.2010.099.

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On-site decentralised wastewater treatment systems can provide a financially attractive alternative to a sewer connection in locations far from existing sewer networks. Operational problems and shortcomings in the design of these systems still occur frequently. The aim of this paper is to provide a low complexity (i.e. easy to calibrate) but still accurate mathematical model that can be used to optimise the operational design of compact individual wastewater treatment systems. An integrated hydraulic and biological carbon removal model of a biofilm-based compact decentralised treatment system is developed. The procedure for drafting the model is generic and can be used for similar types of wastewater treatment systems since (i) the hydraulic model is based on an N-tanks-in-series model inferred from tracer test experiments and (ii) (biofilm) respirometry experiments are exploited to determine the biodegradation kinetics of the biomass. Based on the preliminary validation results of the integrated model, the carbon removal in the system can be predicted quite accurately. While some adjustments could further improve the modelling strategy, the here presented results can already assist the manufacturers of compact treatment systems in efficiently (re)designing their systems.

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Journal articles on the topic 'Hydraulic system validation'

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