naa a22 4500 510765807 CHVBK 20180411083156.0 cr unu---uuuuu 180411e20131201xx s 000 0 eng 10.1007/s11630-013-0657-3 doi (NATIONALLICENCE)springer-10.1007/s11630-013-0657-3 Prediction of dynamic and aerodynamic characteristics of the centrifugal fan with forward curved blades [Elektronische Daten] [Jiří Polanský, László Kalmár, Roman Gášpár] The main aim of this paper is determine the centrifugal fan with forward curved blades aerodynamic characteristics based on numerical modeling. Three variants of geometry were investigated. The first, basic "A” variant contains 12 blades. The geometry of second "B” variant contains 12 blades and 12 semi-blades with optimal length [1]. The third, control variant "C” contains 24 blades without semi-blades. Numerical calculations were performed by CFD Ansys. Another aim of this paper is to compare results of the numerical simulation with results of approximate numerical procedure. Applied approximate numerical procedure [2] is designated to determine characteristics of the turbulent flow in the bladed space of a centrifugal-flow fan impeller. This numerical method is an extension of the hydro-dynamical cascade theory for incompressible and inviscid fluid flow. Paper also partially compares results from the numerical simulation and results from the experimental investigation. Acoustic phenomena observed during experiment, during numerical simulation manifested as deterioration of the calculation stability, residuals oscillation and thus also as a flow field oscillation. Pressure pulsations are evaluated by using frequency analysis for each variant and working condition. Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag Berlin Heidelberg, 2013 Centrifugal nationallicence Fan nationallicence CFD nationallicence Pressure Coefficient nationallicence Flow Coefficient nationallicence A : area A= π D 2/4 nationallicence D : impeller output diameter nationallicence η : efficiency η(p)=Q·Δp T /(M·ω) nationallicence pT nationallicence M nationallicence ω : total pressure, momentum, angular velocity nationallicence $$\dot Q$$ : volume flow rate nationallicence ϕ : flow coefficient (phi) $$\varphi = {{\dot Q} \mathord{\left/ {\vphantom {{\dot Q} {Au_t }}} \right. \kern-\nulldelimiterspace} {Au_t }}$$ nationallicence ψ : pressure coefficient (psi) ψ = 2Δp T / ρ.u t 2 nationallicence ut : tangential velocity nationallicence λ : semi-blade length(Fig.2) λ=(R 2−R 3)/(R 2−R 1) nationallicence Polanský Jiří Univerzitní 8, 306 14, Plzeň, Czech Republic aut Kalmár László Miskolc-Egyetemváros, Miskolc, Hungary aut Gášpár Roman Univerzitní 8, 306 14, Plzeň, Czech Republic aut Journal of Thermal Science Springer Berlin Heidelberg 22/6(2013-12-01), 517-521 1003-2169 22:6<517 2013 22 11630 https://doi.org/10.1007/s11630-013-0657-3 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11630-013-0657-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Polanský Jiří Univerzitní 8, 306 14, Plzeň, Czech Republic aut NATIONALLICENCE 700 1- Kalmár László Miskolc-Egyetemváros, Miskolc, Hungary aut NATIONALLICENCE 700 1- Gášpár Roman Univerzitní 8, 306 14, Plzeň, Czech Republic aut NATIONALLICENCE 773 0- Journal of Thermal Science Springer Berlin Heidelberg 22/6(2013-12-01), 517-521 1003-2169 22:6<517 2013 22 11630 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer