Method and system for detecting the risk of icing on aerodynamic surfaces
View Patent ↗The invention relates to a method and a system for detecting the risk of icing on aerodynamic surfaces lapped by a fluid flow (F), in particular on load-bearing surfaces of fluid machines, of the type comprising a temperature sensor ( 20 ). The system is characterized in that the temperature sensor ( 20 ) is located close to the aerodynamic surface ( 5 S) to be monitored for detecting the temperature of the surface ( 5 S), and that the system comprises a rain sensor ( 30 ) located close to the surface ( 5 S) for detecting the presence of water on that surface ( 5 S). The system can thus detect the risk of icing on aerodynamic surfaces.
1. A method for detecting the risk of icing on aerodynamic surfaces of a machine part exposed to the weather comprising the steps of:
detecting the temperature on said aerodynamic surfaces of said machine part to produce temperature data;
detecting the presence/absence of water in a liquid state on said aerodynamic surfaces of said machine part to produce presence/absence of water data
processing the temperature and presence/absence of water data to generate a risk of icing signal only when water in a liquid state is present on said aerodynamic surfaces of said machine part and the temperature of said aerodynamic surfaces of said machine part is below a preset critical value, and
responding to said risk of icing signal to avoid icing on said aerodynamic surfaces of said machine part.
2. The method according to claim 1 , wherein said machine part is a wind turbine rotor.
3. A system for detecting the risk of icing, said system comprising
a machine part having an aerodynamic surface;
a temperature sensor located on said aerodynamic surface of said machine part for detecting the temperature thereof and producing corresponding temperature data;
a rain sensor located on said aerodynamic surface of said machine part for detecting the presence/absence of water in a liquid state on said aerodynamic surface of said machine part and producing corresponding presence/absence of water data, and
a data acquisition system connected to said sensors which processes said temperature and said presence/absence of water data to provide a risk of icing signal only when water in a liquid state is present on said aerodynamic surface of said machine part and the temperature of said aerodynamic surface of said machine part is below a preset critical value.
4. The system according to claim 3 , wherein, when the sensors detect the presence of water in a liquid state and a temperature below said preset critical value, the data acquisition system sends a said risk of icing signal to a central control unit which initiates action to protect said machine part.
5. The system according to claim 3 , wherein said sensors are arranged in positions corresponding to or surrounding the areas of maximum pressure at said aerodynamic surface of said machine part.
6. The system according to claim 3 , wherein the temperature sensor has a sensing portion exposed to the temperature of said aerodynamic surface of said machine part.
7. The system according to claim 3 , wherein said sensors are arranged on said aerodynamic surface of said machine part close to each other.
8. The system according to claim 7 , wherein said sensors are composed of small plates and are secured to said aerodynamic surface of said machine part.
9. The system according to claim 3 , wherein said sensors are combined in a single unit.
10. The system according to claim 3 , wherein said aerodynamic surface is the outer surface of said machine part of a rotor blade on a wind turbine.
11. The system according to claim 10 , wherein said rotor blade is of a holed type and said sensors are located upstream of a single hole in said aerodynamic surface of said rotor blade.
12. The system according to claim 10 ,
wherein said data acquisition system is arranged on the nacelle of the wind turbine, and includes a transmitter for transmitting said temperature and said presence/absence of water data to a central control unit which initiates action to protect the rotor blade from icing.