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1
Content available CFD analysis of high speed Francis hydraulic turbines
Kaniecki M., Krzemianowski Z.
Transactions of the Institute of Fluid-Flow Machinery
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2016
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nr 131
111--120
EN
The paper presents the computational investigations of model Francis turbines (for high kinematic specific speed 95–115. Numerical calculations were carried out for flow systems including two different Francis runners. The computational fluid dynamics (CFD) analyses were performed for accurately mapped geometry of the laboratory test rig with installed model turbine. Commercial software was used for analysis.
2
Content available Technical diagnostics of hydropower turbine using modern measurement techniques
Żywica G., Kaniecki M.
Diagnostyka
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2016
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Vol. 17, No. 2
87--94
EN
The article demonstrates how to take advantage of modern measurement techniques and detect defects of different types. These techniques contributed to solve the unknown operating problem of a hydropower machine. The examined hydro set comprises a water turbine (of the Francis type), elastic coupling, flywheel and electro-generator. To assess the dynamical state of the machine and detect the reasons for elevated vibration level, the following diagnostic tests were carried out: precision measurement of vibration, laser shaft alignment check and thermal imaging tests. These three widely diverse measurement techniques complemented each other, allowing the identification of the cause of increased vibrations and taking countermeasures to make further operation possible. The article provides an example of the practical application of the currently available vibrodiagnostic methods for monitoring and assessment of the technical condition of fluid-flow machines.
PL
W artykule przedstawiono możliwości nowych technik pomiarowych w zakresie wykrywania różnego typu defektów i problemów eksploatacyjnych na przykładzie rzeczywistej maszyny przepływowej. Badany hydrozespół składał się z turbiny wodnej typu Francisa, podatnego sprzęgła, koła zamachowego oraz generatora prądu. W celu oceny stanu dynamicznego maszyny oraz wykrycia przyczyn podwyższonego poziomu wibroaktywności, przeprowadzono precyzyjne pomiary drgań, laserową kontrolę współosiowości wałów oraz badania termowizyjne. Zastosowane metody pomiarowe doskonale się uzupełniały, pozwalając na wykrycie źródeł drgań oraz zastosowanie środków zaradczych umożliwiających dalszą eksploatację maszyny. Artykuł stanowi przykład praktycznego wykorzystania wszechstronnych możliwości nowoczesnych metod wibrodiagnostycznych do kontroli i oceny stanu technicznego maszyn przepływowych.
3
Content available Discharge measurement and performance tests of hydraulic units in low-head small hydropower installations
Steller J., Adamkowski A., Henke A., Janicki W., Kaniecki M., Krzemianowski Z.
Transactions of the Institute of Fluid-Flow Machinery
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2015
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nr 130
3--29
EN
In course of over half a century the test teams of the Szewalski Institute of Fluid-Flow Machinery (IMP PAN) have conducted numerous performance tests of small hydropower (SHP) installations on various occasions and motivations, including updating or establishing performance characteristics of old machines, acceptance of new units, checking or optimising the cam correlation of new or refurbished double-regulated turbines, checking performance of prototype turbines under field conditions. The discharge measurement techniques have included currentmeter, pressure-time and acoustic methods. Index tests, using the Winter-Kennedy and other differential pressure methods, as well as current-meter and acoustic techniques, have been employed quite frequently to optimise the cam curves of double-regulated machines. In one case a simplified technique based solely on the power/wicket gate opening relationship was checked. This paper discusses some techniques applied when determining the absolute efficiency and optimizing cam correlations by means of absolute and index test methods. Cubic spline formulae as applied to integrate the flow velocity field in a hydrometric section are derived. Results of a discharge measurement by means of the current-meter and pressure-time method are compared as a special case study. Finally, practical recommendations addressed both to the power plant owners and the test team members are formulated.
4
Content available remote A Horizontal Mesh Algorithm for a Class of Edge-bipartite Graphs and their Matrix Morsifications
Kaniecki M., Kosakowska J., Malicki P., Marczak G.
Fundamenta Informaticae
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2015
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Vol. 136, nr 4
345--379
EN
We construct a horizontal mesh algorithm for a study of a special type of mesh root systems of connected positive loop-free edge-bipartite graphs Δ, with n ≥ 2 vertices, in the sense of [SIAM J. Discrete Math. 27 (2013), 827–854] and [Fund. Inform. 124 (2013), 309-338]. Given such a loop-free edge-bipartite graph Δ, with the non-symmetric Gram matrix ˇGΔ ∈ Mn(Z) and the Coxeter transformation ΦA : Zn → Zn defined by a quasi-triangular matrix morsification A ∈ Mn(Z) of Δ satisfying a non-cycle condition, our combinatorial algorithm constructs a ΦA-mesh root system structure Γ(RΔ,ΦA) on the finite set of all ΦA-orbits of the irreducible root system RΔ := {v ∈ Zn; v · ˇGΔ · vtr = 1}. We apply the algorithm to a graphical construction of a ΦI - mesh root system structure Γ(RI ,ΦI ) on the finite set of ΦI -orbits of roots of any poset I with positive definite Tits quadratic form bqI : ZI → Z.
5
Chłodzenie szaf sterowniczych
Kaniecki M.
Technika Chłodnicza i Klimatyzacyjna
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2014
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nr 2
63--66
PL
W materiale omówiono budowę i wyposażenie typowych szaf sterowniczych, w których instalowane są między innymi falowniki. Istotną wadą przemienników częstotliwości jest niska maksymalna temperatura pracy oraz duża wrażliwość na działanie w podwyższonej temperaturze, objawiająca się krótszą ich żywotnością. W dalszej części autor przybliża dostępne sposoby chłodzenia szaf sterowniczych wraz z ich krótką charakterystyka techniczną.
EN
The material discussed in the construction and equipment of typical control cabinets, which are installed between the other inverters. A significant drawback of frequency converters is low maximum operating temperature and high sensitivity to the effects of elevated temperatures, reflected in shorter their life. Later in the author describes the available methods of cooling cabinets along with their brief technical characteristics.
6
Content available Computational fluid dynamics simulations of small capacity Kaplan turbines
Kaniecki M., Krzemianowski Z., Banaszek M.
Transactions of the Institute of Fluid-Flow Machinery
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2011
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nr 123
71-84
EN
In the presented paper authors focused on numerical analysis of the flow through selected constructions of Kaplan and semi-Kaplan machines. The paper contains three computation examples; each of them concentrates on different aspects of computational fluid dynamics (CFD) utilization. The numerical tests of various turbulent models for Kaplan turbine CFD applications, numerical determination of the cam curve characteristic and numerical analysis of operating parameters of the semi-Kaplan machine have been presented. The methodology of the implemented numerical computations and final results of calculations have been discussed in each of the presented study cases.
7
Content available remote Flow Analysis through Axial-Flow Pumps by Means of the Lattice Vortex Method
Kaniecki M.
Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka
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2005
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nr 128, vol. 1
273-280
EN
The paper presents results of numerical flow computation through axial-flow pumps. The calculation method (lattice vortex method) is one of the variety of boundary elements methods, based on the potential flow equation. Brief characteristics of the method and the calculation results of global characteristics of two selected axial-flow pumps are presented.
8
Content available remote Modernization of the outflow system of cross-flow turbines
Kaniecki M.
TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
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2002
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Vol. 6, No 4
601-608
EN
The presented article brings general overview of CFD analysis of two cross-flow turbine types (a classical impulse turbine and a reaction turbine). The author focuses his attention mainly on the discussion of differences in flow patterns in the outflow section of these turbines, because this element exerts significant impact on performance properties of the turbine. The article presents a comparison of computations and experimental results of the cross-flow turbine manufactured by IMP PAN. The analysis was performed by means of a computer program FLUENT for a two-dimensional example.
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