Assessment of Water Measurements in an Irrigation Canal System Based on Experimental Data and the CFD Model

Due to their convenience, water measuring structures have become an important means of measuring water in irrigation canal systems However, relevant research on upstream and downstream water-depth monitoring point locations is scarce. Our study aims to determine the functional relationship between the locations of the water-depth monitoring points and the opening width of the sluice. We established 14 trunk-channel and branch-channel hydrodynamic models. The locations of the water-depth monitoring points for the upstream and downstream reaches and their hydraulic characteristics were assessed using a numerical simulation and hydraulic test. The results showed that the locations of the upstream and downstream water-depth monitoring points were, respectively, 16.26 and 15.51 times the width of the sluice. The average error between the calculated flow rate and the simulated value was 14.37%; the average error between the flow rates calculated by the modified and the simulated values was 3.36%. To further verify the accuracy of the modified discharge calculation formula, by comparing the measured values, we reduced the average error of the modified formula by 19.29% compared with the standard formula. This research provides new insights into optimizing water measurements in irrigation canal systems. The results provide an engineering basis for the site selection of water-depth monitoring points that is suitable to be widely applied in the field.

Hydraulic Test Stand to Model Circulatory System Dynamics for Artificial Heart Evaluation

This work proposes the theory and design of an experimental setup to mimic the dynamic impedance of the human circulatory system for testing the dynamic characteristics of an artificial heart. This platform has the same resistance, compliance, and inertance elements as the well-studied 4-element Windkessel model. As opposed to a circuit analogy model commonly seen in the literature, our platform remains within the same energy domain as the circulatory system. This allows an artificial heart designer to test pump performance and dynamic pressure characteristics under realistic loading. A test platform is designed using a non-hazardous working fluid with the same density and viscosity as blood. The system uses as few custom components as possible and interchangeable parts allow for system tuning.

Development of Glycerin/Chitosan-Based Fluids for Stationary and Mobile Hydraulic Drives

A hydraulic fluid based on water, glycerol and the thickener chitosan was developed in preliminary tests at Technische Universität Braunschweig. In terms of fluid properties, the fluid is comparable to those of conventional fluids. Due to the promising properties of the fluid, further development of the fluid is now being worked on. The focus is on further development for practical use in mobile hydraulic systems, e.g. in agricultural and forestry machinery. The aim here is to optimize various fluid variants for different applications and to define the possible range of uses in general. This paper presents interim results from the development of the fluids and the investigations of the fluids in a wide range of laboratory tests and endurance tests in a hydraulic test bench.

Hydrodynamic improvement by adding inlet baffles on centrifugal pump for reducing cavitation instabilities

Cavitation instability is a common phenomenon that causes vibration and noise of turbomachinery. In this study, an attempt is made to suppress the cavitation instability. A high-speed centrifugal pump with inducer is taken as the research objective. Four baffles are evenly arranged at the inlet of the inducer as a hydrodynamic improvement. The energy characteristics of the pump are measured on a closed hydraulic test rig. The pressure, vibration, and noise under different flow rates and different cavitation number are acquired for comparative analyses. Experimental results show that the energy characteristics changed after hydrodynamic improvement. The original pump is mainly affected by y-direction vibration and is clearly suppressed in the new pump. The low-frequency pressure pulsation under partial flow rate condition can be effectively suppressed. The baffles can also reduce the broadband center frequency at the pump outlet and change the relationship between center frequency and cavitation number. These results show that the hydrodynamic improvement at the inlet helps the suppression of cavitation instability of the high-speed centrifugal pump.

The H2020 McSAFER Project: Main Goals, Technical Work Program, and Status

This paper describes the main objectives, technical content, and status of the H2020 project entitled “High-performance advanced methods and experimental investigations for the safety evaluation of generic Small Modular Reactors (McSAFER)”. The main pillars of this project are the combination of safety-relevant thermal hydraulic experiments and numerical simulations of different approaches for safety evaluations of light water-cooled Small Modular Reactors (SMR). It describes the goals, the consortium, and the involved thermal hydraulic test facilities, e.g., the COSMOS-H (KIT), HWAT (KTH), and MOTEL (LUT), including the experimental programs. It also outlines the different safety assessment methodologies applied to four different SMR-designs, namely the CAREM (CNEA), SMART (KAERI), F-SMR (CEA), and NuScale. These methodologies are multiscale thermal hydraulics, conventional, low order, and high fidelity neutron physical methods used to demonstrate the inherent safety features of SMR-core designs under postulated design-basis-accident conditions. Finally, the status of the investigations is shortly discussed followed by the dissemination activities and an outlook.

Development of metallic 3d-printed water hydraulic proportional directional control valve

New additive metal powder technologies are increasingly used for various prototypes. Different powder materials can be used for very complex shapes. Water hydraulics needs new technologies and new approaches to enable more frequent use by users. A new shape of housing for a water hydraulic proportional directional control valve was designed. FEM and CFD analyses of the valve housing were performed. Based on the results of the initial numerical analyses, topological optimization of the valve housing was performed. The prototype of the valve was fabricated from non-corrosive Inconel powder using 3D printing process. After machining, the valve was assembled and experimentally validated on the water hydraulic test rig. The new 3D-printed Inconel valve housing is more than 3 times lighter than similar housings of industrial valves.

Application of Smooth Particle Hydrodynamics to Particular Flow Cases Solved by Saint-Venant Equations

Smoothed particle hydrodynamics (SPH) is a Lagrangian mesh free particle method which has been developed and widely applied to different areas in engineering. Recently, the SPH method has also been used to solve the shallow water equations, resulting in (SPH-SWEs) formulations. With the significant developments made, SPH-SWEs provide an accurate computational tool for solving problems of wave propagation, flood inundation, and wet-dry interfaces. Capabilities of the SPH method to solve Saint-Venant equations have been tested using a SPH-SWE code to simulate different hydraulic test cases. Results were compared to other established and commercial hydraulic modelling packages that use Eulerian approaches. The test cases cover non-uniform steady state profiles, wave propagation, and flood inundation cases. The SPH-SWEs simulations provided results that compared well with other established and commercial hydraulic modeling packages. Nevertheless, SPH-SWEs simulations experienced some drawbacks such as loss of inflow water volume of up to 2%, for 2D flood propagation. Simulations were carried out using an open source solver, named SWE-SPHysics.

An Adaptive Control Combination Forecasting Method for Time Series Data

According to the individual forecasting methods, an adaptive control combination forecasting (ACCF) method with adaptive weighting coefficients was proposed for short-term prediction of the time series data. The US population dataset, the American electric power dataset, and the vibration signal dataset in a hydraulic test rig were separately tested by using ACCF method, and then, the accuracy analysis of ACCF method was carried out in the study. The results showed that, in contrast to individual methods or combination methods, the proposed ACCF method was adaptive to adopt one or some of prediction methods and showed satisfactory forecasting results due to flexible adaptability and a high accuracy. It was also concluded that the higher the noise ratio of the tested datasets, the lower the prediction accuracy of the ACCF method; the ACCF method demonstrated a better prediction trend with good volatility and following quality under noisy data, as compared with other methods.