...Jin-Hyuk Kim; Jae-Woo Kim; Kwang-Yong Kim This paper presents an optimization procedure for axial-flow ventilation fan design through a hybrid multiobjective evolutionary algorithm (MOEA) coupled with a response surface approximation (RSA) surrogate model. Numerical analysis of a preliminary fan...

...David Greenblatt On the basis of a semi-empirical model, large Gurney flaps of 10%, 20%, and 30% of the fan blade chord length were tested in a specially designed ventilation fan facility. At the highest volumetric flowrates tested, the flapped blades all produced higher pressures than the baseline...

...Pramod B. Salunkhe; A. M. Pradeep The present paper describes the use of Morlet wavelet transform in understanding the stall inception mechanism in a single stage axial flow fan. Unsteady pressure data from wall mounted sensors were used in the wavelet transforms. This paper was carried out under...

... were found to be O(0.5), irrespective of the blade orientation or number of blades. Moreover, the maximum pressure rise was achieved with an investment of only 2% of the fan input power. Backward bladed impeller blades exhibited slightly larger increases in pressure coefficients when compared...

...Matjaž Eberlinc; Brane Širok; Matevž Dular; Marko Hočevar Axial fans often show adverse flow conditions at the fan hub and at the tip of the blade. The modification of conventional axial fan blade is presented. Hollow blade was manufactured from the hub to the tip. It enables the formation of self...

...Alessandro Corsini; Franco Rispoli; A. G. Sheard This study assesses the effectiveness of modified blade-tip configurations in achieving passive noise control in industrial fans. The concepts developed here, which are based on the addition of end-plates at the fan-blade tip, are shown to have...

...D. Sui; S. S. Wang; J. R. Mao; T. Kim; T. J. Lu The exit flow patterns of an axial flow fan widely used in electronics cooling are experimentally characterized both in free exit and in the presence of a flat impingement plate. The axial fan is rotated with 12.0 V input from a dc power supply...

...David Quin; Ronan Grimes Microscale axial flow fans were investigated in response to the growing cooling requirements of the electronics industry. The two main challenges of this investigation were manufacture of a fully functional fan at the microscale, and performance reduction due to Reynolds...

...Rafael Ballesteros-Tajadura; Sandra Velarde-Suárez; Juan Pablo Hurtado-Cruz Centrifugal fans are widely used in several applications, and in some cases, the noise generated by these machines has become a serious problem. The centrifugal fan noise is frequently dominated by tones at the blade...

...Jesús Manuel Fernández Oro; Rafael Ballesteros-Tajadura; Eduardo Blanco Marigorta; Katia María Argüelles Díaz; Carlos Santolaria Morros This paper analyzes the structure of turbulence and secondary flows at the exit of an axial flow fan with variable pitch blades. The influence of changing...

...Jesús Manuel Fernández Oro; Katia María Argüelles Díaz; Carlos Santolaria Morros; Eduardo Blanco Marigorta This paper is conceived as an extension in the analysis of the periodic stator-rotor interaction in a low-speed axial fan with inlet guide vanes. Here, the present work focuses...

...D. R. Neal; J. F. Foss An experimental investigation of an aerodynamic shroud applied to an axial ventilation fan system is reported. The aerodynamic shroud consists of a pressurized plenum and Coanda attachment surface, which also serves as the shroud for the fan. This combination delivers...

...Hauke Reese; Chisachi Kato; Thomas H. Carolus A large eddy simulation (LES) was applied to predict the unsteady flow in a low-speed axial-flow fan assembly subjected to a highly “turbulent” inflow that is generated by a turbulence grid placed upstream of the impeller. The dynamic Smagorinsky model...

...Gianluca Iaccarino; Stéphane Moreau The Cartesian incompressible RANS solver with immersed boundaries, IBRANS , recently developed at Stanford, has been extended to include conjugate heat transfer modeling and used for the simulation of the electrical motor of an automotive engine cooling fan...

...A. Behzadmehr; Y. Mercadier; N. Galanis Centrifugal fans with an electric motor included in the hub are commonly used in HVAC (heating, ventilation, and air conditioning) systems. A design of experiments (DOE) has been performed to study the effect of the entrance conditions of a backward-inclined...

...S. C. Yen; Frank K. T. Lin Flow fields near the exit and the global performance parameters of the various types of axial flow fans are studied with Particle Image Velocimetry and a standard AMCA 210 flow bench. The fans used in this study included the shrouded, shroudless, and winglet-blade types...

...Rafael Ballesteros-Tajadura; Sandra Velarde-Suárez; Juan Pablo Hurtado-Cruz; Carlos Santolaria-Morros In this work, a numerical model has been applied in order to obtain the wall pressure fluctuations at the volute of an industrial centrifugal fan. The numerical results have been compared...

...Sofiane Khelladi; Smaïne Kouidri; Farid Bakir; Robert Rey In order to better understand the behavior of the fluid flow in vaned centrifugal fans, theoretical and experimental work has been carried out on unsteady three-dimensional (3D) flows. Particular attention is given to the flows located...

...Xiaocheng Zhu; Wanlai Lin; Zhaohui Du The tip leakage flow in an axial ventilation fan with various tip clearances is investigated by experimental measurement and numerical simulation. For a low-rotating-speed ventilation fan with a large tip clearance, both experimental measurement and numerical...

...C.-M. Jang; D. Sato; T. Fukano The flow characteristics in the blade passage and in the wake region of a low-speed axial flow fan have been investigated by experimental analysis using a rotating hot-wire sensor and a five-hole probe for design and off-design operating conditions. The results show...