Author:
Publisher:
ISBN:
Category : Aircraft gas-turbines
Languages : en
Pages : 212
Book Description
Proceedings of the Annual National Conference on Environmental Effects on Aircraft and Propulsion Systems
Author:
Publisher:
ISBN:
Category : Aircraft gas-turbines
Languages : en
Pages : 212
Book Description
Publisher:
ISBN:
Category : Aircraft gas-turbines
Languages : en
Pages : 212
Book Description
ARS.
Author:
Publisher:
ISBN:
Category : Agriculture
Languages : en
Pages : 992
Book Description
Publisher:
ISBN:
Category : Agriculture
Languages : en
Pages : 992
Book Description
Proceedings of the Joint Symposium on Environmental Effects on VTOL Designs
Author:
Publisher:
ISBN:
Category : Helicopters
Languages : en
Pages : 576
Book Description
Publisher:
ISBN:
Category : Helicopters
Languages : en
Pages : 576
Book Description
ESSA Science and Engineering
Author: United States. Environmental Science Services Administration
Publisher:
ISBN:
Category : Environmental sciences
Languages : en
Pages : 164
Book Description
Publisher:
ISBN:
Category : Environmental sciences
Languages : en
Pages : 164
Book Description
ESSA Science and Engineering, July 31, 1965 to June 30, 1967
Author: United States. Environmental Science Services Administration
Publisher:
ISBN:
Category :
Languages : en
Pages : 164
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 164
Book Description
ESSA Science and Engineering, July 13, 1965 to June 30, 1967
Author: United States. Environmental Science Services Administration
Publisher:
ISBN:
Category : Hydrology
Languages : en
Pages : 174
Book Description
Publisher:
ISBN:
Category : Hydrology
Languages : en
Pages : 174
Book Description
Microfabricated Ice-Detection Sensor
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 16
Book Description
Knowledge of ice conditions on important aircraft lift and control surfaces is critical for safe operation. These conditions can be determined with conventional ice detection sensors, but these sensors are often expensive, require elaborate installation procedures, and interrupt the airflow. A micromachined, silicon based, flush mounted sensor which generates no internal heat has been designed, batch fabricated, packaged, and tested. The sensor is capable of distinguishing between an ice covered and a clean surface. It employs a bulk micromachined wafer with a 7 micrometers thick, boron doped, silicon diaphragm which serves as one plate of a parallel plate capacitor. This is bonded to a second silicon wafer which contains the fixed electrodes; one to drive the diaphragm by application of a voltage, the other to measure the deflection by a change in capacitance. The diaphragm sizes ranged from 1x1mm to 3x3mm, and the gap between parallel plate capacitors is 2 micrometers. A 200V d.c. was applied to the driving electrode which caused the capacitance to increase approximately 0.6pf from a nominal capacitance of 0.6pf when the surface was ice free. After the sensor was cooled below the freezing point of water, the same voltage range was applied to the drive electrode. The capacitance increased by the same amount. Then a drop of water was placed over the diaphragm and allowed to freeze. This created an approximately 2mm thick ice layer. The applied 200V d.c. produced no change in capacitance, confirming that the diaphragm was locked to the ice layer. Since the sensor uses capacitive actuation, it uses very little power and is an ideal candidate for inclusion in a wireless sensing system.
Publisher:
ISBN:
Category :
Languages : en
Pages : 16
Book Description
Knowledge of ice conditions on important aircraft lift and control surfaces is critical for safe operation. These conditions can be determined with conventional ice detection sensors, but these sensors are often expensive, require elaborate installation procedures, and interrupt the airflow. A micromachined, silicon based, flush mounted sensor which generates no internal heat has been designed, batch fabricated, packaged, and tested. The sensor is capable of distinguishing between an ice covered and a clean surface. It employs a bulk micromachined wafer with a 7 micrometers thick, boron doped, silicon diaphragm which serves as one plate of a parallel plate capacitor. This is bonded to a second silicon wafer which contains the fixed electrodes; one to drive the diaphragm by application of a voltage, the other to measure the deflection by a change in capacitance. The diaphragm sizes ranged from 1x1mm to 3x3mm, and the gap between parallel plate capacitors is 2 micrometers. A 200V d.c. was applied to the driving electrode which caused the capacitance to increase approximately 0.6pf from a nominal capacitance of 0.6pf when the surface was ice free. After the sensor was cooled below the freezing point of water, the same voltage range was applied to the drive electrode. The capacitance increased by the same amount. Then a drop of water was placed over the diaphragm and allowed to freeze. This created an approximately 2mm thick ice layer. The applied 200V d.c. produced no change in capacitance, confirming that the diaphragm was locked to the ice layer. Since the sensor uses capacitive actuation, it uses very little power and is an ideal candidate for inclusion in a wireless sensing system.
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 702
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 702
Book Description
NASA Scientific and Technical Publications
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 134
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 134
Book Description
National Union Catalog
Author:
Publisher:
ISBN:
Category : Union catalogs
Languages : en
Pages : 1032
Book Description
Includes entries for maps and atlases.
Publisher:
ISBN:
Category : Union catalogs
Languages : en
Pages : 1032
Book Description
Includes entries for maps and atlases.