Here below we post a list of
Papers already accepted for publication in Issue 1/2020 of HIDRAULICA Magazine.
The list displays paper title, author(s) and affiliation, and also paper abstract.
Full-length paper will be available online only after publication.
Procedural and Methodological Example of Gravimetric Measurement of Pollutant Particles in the Environment using Sampling Devices
PhD Candid. Melania MITUCĂ-CORLECIUC1, Assoc.prof.PhD.eng. Ion DURBACĂ1, PhD Eng. George SORESCU2, PhD Candid. Cosmin Gheorghe CIOCOIU1, PhD Candid. Luana NISTEA1, PhD Candid. Vasile SĂCUIU1
1POLITEHNICA University of Bucharest, Romania
2 General Inspectorate for Emergency Situations, Romania
This paper deals, using a demonstrative example, with the methodological procedure of gravimetric measurement of the polluting particles, according to the standard SR EN 12341/2014, for the real evaluation of the 10 μm particle in the biphasic suspensions discharged into the environment. The procedure can be used to compare a non-certified measuring instrument with a reference instrument by verifying that the conditions for the difference between the particle-specific concentration of the particulate immissions (<± 10 μg / m3) and their concentration in the environment (< 100 μg / m3). The mathematical processing of the comparative results through the regression equation must verify that a correlation coefficient value is obtained to validate the fulfillment of the standard requirements.
Transients in Public Water Supply in Győr-Moson-Sopron County
Assistant professor PhD Student Nikolett FECSER1
1Széchenyi István University, Gyor, Hungary
Transient is a flow condition in which the velocity and pressure change rapidly with time. Transient operating states place such extreme loads on the pipes that they might cause burst water pipes. To highlight the importance of transient phenomena, I present the measurements carried out at Pannon-Víz Zrt and their results in my study. By this research, I aim to raise awareness about the dangers of transient phenomena in water supply systems. Furthermore, I wish to improve the operational safety and efficiency of water supply systems.
Gradually Varied Flow in a Trapezoidal Channel, towards a Hydraulics with Fractional Calculation and Finite Differences
Student Carlos A. SANTAMARÍA DÍAZ1, Dra. Maritza L. ARGANIS JUÁREZ1,
Dr. José L. ARAGÓN HERNÁNDEZ1, Dr. José L. HERRERA ALANÍS1,
M.A. Jesús J. CORTÉS ROSAS1, M.A. Miguel E. GONZÁLEZ CÁRDENAS1,
M.A. Víctor D. PINILLA MORÁN1, M.I. Margarita E. PRECIADO JIMÉNEZ2
1 Universidad Nacional Autónoma de México
2 Instituto Mexicano de Tecnología del Agua
Several engineering problems involve use a derivative of a function; in recent years, physical phenomena have been reviewed are traditionally considered to be derived with an integer order in their mathematical models, instead derived with fractional order. Gradually varied flow evaluation profile in a free-surface channel is traditionally resolved with differential calculus and integer derivatives solved with finite difference schemes. In this work, equations were obtained relate derivatives of half order derivative of first order for different algebraic functions, resulting in polynomial type models; since there is a proportion between first derivative with derivatives of fractional order through these expressions and observing flow profiles can adjust a y(x) function approximately polynomial it is established various tests must be done to approximate to gradually varied flow equation solution help fractional differential equations can be solved through fractional finite differences.
Experimental Research on the Processing of Concave Spherical Surfaces with Toroidal Mills Versus Spherical Mills
PhD. Student Eng. Andrei OȘAN1
1Technical University of Cluj-Napoca – North University Center of Baia Mare, Romania
The quality of the surface plays a very important role on the wear layer of the piece. There must be a balance so that the roughness is not too high but not too low. To determine the optimum roughness, several process factors must be correlated so that the results are the desired ones. This work aims to determine the roughness on the concave spherical surfaces. In order to determine it, the process factors but also the geometrical shape of the tool vary. As an additional argument in determining the optimal values, the execution time of each experiment is also pursued.
Continuous Lubrication Systems for Machine Tools
Prof. PhD Eng. Anca BUCUREȘTEANU1, Prof. PhD Eng. Dan PRODAN1,
Assoc. Prof. PhD Eng. Adrian MOTOMANCEA1, Assistant Alina OVANISOF1
1University POLITEHNICA of Bucharest, Romania
This paper describes some of the results obtained by the authors in the design, simulation and testing of the lubrication units for machine tools. The paper is based on the data collected during the manufacture of a boring and milling machine tool with numerical control (AF 105 CNC). The study includes theoretical considerations, calculations and simulation of unit operation but also explanations on the actual manufacture of the unit. Several machines were built on the basis of this project. The proper selection of the components, the making of calculations and simulation helped to the manufacture of an efficient unit with low noise and reduced heat.
Establishing the Mathematical Relation between the Rotor Radius and the Height of the Rotating Piston for a Rotating Machine
PhD Student Mariana Mirela STOICAN (PRISECARU)1, Prof. Dr. Eng. Nicolae BĂRAN2, PhD Student Almaslamani Ammar Fadhil SHNAWA1
1University Politehnica of Bucharest, Romania
Mathematically, the paper establishes a link between the constructive elements, the rotor radius and the height of the rotating piston, which is part of the construction of a machine with profiled rotors that transports fluids.
For a certain constructive solution, the maximum height of the rotating piston is set; the influence of the height of the piston on the flow rate and the driving power of the machine are highlighted.
A constructive solution which allows the maximum power of the machine is presented.