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Since the flow both enters and exits the impeller radially, the crossflow fan has been studied and prototyped for potential aircraft applications.<ref>{{Cite journal |last1=Himeur |first1=Rania M. |last2=Khelladi |first2=Sofiane |last3=Ait Chikh |first3=Mohamed Abdessamed |last4=Vanaei |first4=Hamid Reza |last5=Belaidi |first5=Idir |last6=Bakir |first6=Farid |date=January 2022 |title=Towards an Accurate Aerodynamic Performance Analysis Methodology of Cross-Flow Fans |journal=Energies |language=en |volume=15 |issue=14 |pages=5134 |doi=10.3390/en15145134 |issn=1996-1073 |doi-access=free }}</ref> Due to the two-dimensional nature of the flow, the fan can be integrated into a wing for use in both thrust production and boundary-layer control. A configuration that utilizes a crossflow fan is located at the wing [[leading edge]] is the [[FanWing]] design concept initially developed around 1997 and under development by a company of the same name. This design creates lift by deflecting the wake downward due to the rotational direction of the fan, causing a large [[Magnus effect|Magnus force]], similar to a spinning leading-edge cylinder. Another configuration utilizing a crossflow fan for thrust and flow control is the [[propulsive wing]], another experimental concept prototype initially developed in the 1990s and 2000s. In this design, the crossflow fan is placed near the [[trailing edge]] of a thick wing and draws the air of the wing's suction (top) surface. By doing this, the propulsive wing is nearly stall-free, even at extremely high angles of attack, producing very high lift. However, the fanwing and propulsive wing concepts remain experimental and have only been used for unmanned prototypes.
A cross-flow fan is a centrifugal fan in which the air flows straight through the fan instead of at a right angle. The rotor of a cross-flow fan is covered to create a pressure differential. Cross-flow fans are made to have a double circular arc rear wall with a thick vortex wall that decreases in radial gap. The gap decreases in the direction of the fans impeller rotation. The rear wall has a log-spiral profile while the vortex stabilizer is a horizontal thin wall with rounded edge.<ref>{{Cite journal|last1=Casarsa|first1=L.|last2=Giannattasio|first2=P.|date=September 2011|title=Experimental study of the three-dimensional flow field in cross-flow fans|url=http://dx.doi.org/10.1016/j.expthermflusci.2011.01.015|journal=Experimental Thermal and Fluid Science|volume=35|issue=6|pages=948–959|doi=10.1016/j.expthermflusci.2011.01.015|bibcode=2011ETFS...35..948C |issn=0894-1777}}</ref> The resultant pressure difference allows air to flow straight through the fan, even though the fan blades counter the flow of air on one side of the rotation. Cross-flow fans give airflow along the entire width of the fan; however, they are noisier than ordinary centrifugal fans. Cross-flow fans are often used in ductless [[air conditioner]]s, [[air door]]s, in some types of [[laptop cooler]]s, in automobile ventilation systems, and for cooling in medium-sized equipment such as [[photocopier]]s.
=== Bladeless fans ===
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