Experimental Heat Loads for Electrothermal Anti-Icing and De-Icing on UAVs

Abstract

Atmospheric in-flight icing on unmanned aerial vehicles (UAVs) is a significant hazard. UAVs that are not equipped with ice protection systems are usually limited to operations within visual line of sight or to weather conditions without icing risk. As many military and commercial UAV missions require flights beyond visual line of sight and into adverse weather conditions, energy-efficient ice protection systems are required. In this experimental study, two electro-thermal ice protection systems for fixed-wing UAVs were tested. One system was operated in anti-icing and de-icing mode, and the other system was designed as a parting strip de-icing system. Experiments were conducted in an icing wind tunnel facility for varying icing conditions at low Reynolds numbers. A parametric study over the ice shedding time was used to identify the most energy-efficient operation mode. The results showed that longer intercycle durations led to higher efficiencies and that de-icing with a parting strip was superior compared to anti-icing and de-icing without a parting strip. These findings are relevant for the development of energy-efficient systems in the future.

Fixed Wing Aircraft Automatic Landing with the Use of a Dedicated Ground Sign System

“…A raw picture captured by an on-board video camera containing both red and yellow circles is first transformed from the RGB to the HSV model of colors (Figure 6a) [39]. Next, a sixfold binarization (for each red and yellow component) with double thresholding H, S, V components for yellow and red is defined by (2). The first three operations extract objects in red, and the next three extract objects in yellow.…”

“…Systems of various types of Unmanned Aerial Vehicles (UAV), including fixed wings [1][2][3], multirotor [4][5][6] and other hybrid type aircraft [7,8] are increasingly being used in both military and civilian applications. An increasing number of flying platforms, greater availability of entire UAV systems and new types of missions, make issues related to the full automation of the entire flight, including its terminal phases, more and more important.…”

A sandwich-structured intelligent anti-icing/de-icing film with ice-oriented power self-regulating performance

“…From traditional mechanical and thermal de-icing techniques to bio-inspired passive anti-icing methods, and then to integrated active/passive anti-icing and de-icing solutions, a lot of work has been done towards the requirements for highly efficient, energy-saving and lightweight anti-icing/ de-icing applications. 1 Among these techniques, traditional thermal anti-icing techniques have been the most widely applied due to their reliability and direct response, yet have fallen short of the allweather flight requirements for UAVs with insufficient energy 2 and aircrafts with large proportion of low-thermal-conductivity composite materials. 3,4 Based on this situation, bio-inspired passive anti-icing surfaces have sprung up to fill the vacancy of anti-icing techniques without energy consumption, including superhydrophobic surfaces from lotus leaves, [5][6][7][8][9][10] slippery liquid-infused porous surfaces (SLIPS) from Nepenthes, [11][12][13][14] coatings with aqueous lubricating layers or polymer brushes, [15][16][17] low-interfacial toughness materials, 18 etc.…”

“…Among these techniques, traditional thermal anti-icing techniques have been the most widely applied due to their reliability and direct response, yet have fallen short of the all-weather flight requirements for UAVs with insufficient energy 2 and aircrafts with large proportion of low-thermal-conductivity composite materials. 3,4 Based on this situation, bio-inspired passive anti-icing surfaces have sprung up to fill the vacancy of anti-icing techniques without energy consumption, including superhydrophobic surfaces from lotus leaves, 5–10 slippery liquid-infused porous surfaces (SLIPS) from Nepenthes , 11–14 coatings with aqueous lubricating layers or polymer brushes, 15–17 low–interfacial toughness materials, 18 etc.…”

Behavior of Sliding Angle as Function of Temperature Difference between Droplet and Superhydrophobic Coating for Aircraft Ice Protection Systems

“…However, energy efficiency using bleed air has been an issue, as these systems are energetically and economically expensive [6][7][8][9]. A hybrid anti-/de-icing system combining a superhydrophobic coating with an electrothermal heater has recently been proposed to reduce energy consumption [10][11][12][13]. Ice accretion over the leading edge of a wing is melted by the heater.…”