Design and Characterization of a Bearingless Cross-Flow Fan

Author(s):  
Ivana Bagaric ◽  
Daniel Steinert ◽  
Florian Wassmer ◽  
Thomas Holenstein ◽  
Thomas Nussbaumer ◽  
...  
Keyword(s):  
2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Huanxin Lai ◽  
Meng Wang ◽  
Chuye Yun ◽  
Jin Yao

This paper presents a qualitative analysis of controlling the cross-flow fan noise by using porous stabilizers. The stabilizer was originally a folded plate. It is changed into a porous structure which has a plenum chamber and vent holes on the front wall. In order to investigate the influences of using the porous stabilizers, experiments are carried out to measure the cross-flow fan aerodynamic performances and sound radiation. Meanwhile, the internal flow field of the fan is numerically simulated. The results show that the porous stabilizers have not produced considerable effect on the cross-flow fan's performance curve, but the noise radiated from the fan is strongly affected. This indicates the feasibility of controlling the cross-flow fan noise by using the porous stabilizers with selected porosity.


2015 ◽  
Vol 78 ◽  
pp. 44-54 ◽  
Author(s):  
Anthony Oswaldo Roque Ccacya ◽  
Luís Fernando Figueira da Silva
Keyword(s):  

Author(s):  
Hironobu Yamakawa

Cross flow fans are used for fan systems in a household room air conditioner indoor unit. In recently, in the view of environmental problem and cost saving, energy saving performance is important specification for users. Reducing fan motor electric power consumption is effective for this purpose. And also low noise fans are needed for comfortable circumferences. To meet these user needs, we developed a high efficiency and silent cross flow fan using CFD (Computational Fluid Dynamics) and experiments. In CFD, numerical model is calculated by commercial software using steady state, Reynolds-averaged Navier-Stokes (RANS) and k-ε turbulent flow model. The developed cross flow fan is geometrically characterized by the solidity (the ratio of the blade pitch and blade cord length) distribution, and the blade edge shape. The solidity average of developed fan was larger than the conventional fan and the solidity distribution was smooth. And the developed fan has the sinusoidal shape of the outer diameter edge. This sinusoidal shape edge makes pressure distribution on the tongue to be more dispersed compare to that of conventional straight edge so that tonal noise was restrained.


2016 ◽  
Vol 88 (6) ◽  
pp. 783-790 ◽  
Author(s):  
Lin Meng ◽  
Yongqiang Ye

Purpose This paper aims to study the short take-off characteristics and longitudinal controllability of FanWing. As a new structural plane, it has achieved great success at the air shows, but the existing literature is mostly on feasibility and prototype study while little on short take-off performance analysis and controllability. Thus, the paper will do some research on those two aspects. Design/methodology/approach This paper focuses on a certain type of a 3.5 kg FanWing and builds the longitudinal model based on its structure characteristics and operation principle. Its take-off process is simulated and the longitudinal control law is designed. Findings The short take-off performance and the large load characteristic are verified. To attain a better short take-off performance, several factors that influence the take-off distance are researched, and the optimal no-load take-off distance 5 m is obtained when the elevator deflection angle is −30°, the center of gravity is 0.42 m and the cross-flow fan rotation speed is 2500 r/min. The longitudinal controllability is verified through simulation. And without variable cross-flow fan rotation speed control, the longitudinal control of FanWing is the same to that of the conventional aircraft. Practical implications The presented efforts provide markers for designing the fan wing aircraft that would have better performances. And the control of FanWing is similar to that of a conventional airplane. Originality/value It is proved that FanWing can offer a better take-off performance through reasonable configuration. The paper also offers a useful reference on the control of FanWing.


Author(s):  
Florent Colomb ◽  
Stanislav Karpuk ◽  
Marina Kazarina ◽  
Vladimir V. Golubev ◽  
Reda R. Mankbadi

Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 959
Author(s):  
Weijie Zhang ◽  
Jianping Yuan ◽  
Qiaorui Si ◽  
Yanxia Fu

Cross-flow fans are widely used in numerous applications such as low-pressure ventilation, household appliances, laser instruments, and air-conditioning equipment. Cross-flow fans have superior characteristics, including simple structure, small size, stable airflow, high dynamic pressure coefficient, and low noise. In the present study, numerical simulation and experimental research were carried out to study the unique secondary flow and eccentric vortex flow characteristics of the internal flow field in multi-operating conditions. To this end the vorticity and the circumferential pressure distribution in the air duct are obtained based on the performed experiments and the correlation between spectral characteristics of multiple operating conditions and the inflow state is established. The obtained results show that when the area of the airflow passage decreases while the area of the eccentric vortex area gradually increases, then the airflow of the cross-flow fan decreases, the outlet expands, and the flow pattern uniformity reduces. It was found that wakes form in the vicinity of the blade and the tail of the volute tongue, which generate pressure pulsation, and aerodynamic noise. The pressure distribution along the inner circumference shows that the total minimum pressure appears in the eccentric vortex near the volute tongue and the volute returns near the zone. Moreover, it was found that the total pressure near the eccentric vortex is significantly smaller than that of the main flow zone. As the flow rate decreases, the pressure pulsation amplitude of the eccentric vortex region significantly increases, while the static and total pressure pulsation amplitudes are gradually increased. Close to the eccentric vortex on the inner side of the blade in the volute tongue area, total pressure is low, total pressure on the outside of the blade is not affected, and pressure difference between the inner and outer sides is large. When the flow rate of the cross-flow fan is 0.4 Qd, there is no obvious peak at the harmonic frequency of the blade passage frequency. This shows that the aerodynamic noise is caused by the main unstable flow.


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