Stable Floating Drops of Liquid

1985 ◽  
Vol 107 (4) ◽  
pp. 530-533
Author(s):  
Peter Dransfield ◽  
D. C. Davis
Keyword(s):  
Rotational Speed ◽  
Ambient Conditions ◽  
Speed Sensor ◽  
Floating Drops

There are few reported situations in which a drop of liquid will remain intact in ambient conditions for an indefinite period of time. The paper describes a situation where this happens. The phenomenon was noticed during experiments concerned with the development of a novel rotational speed sensor. It proved to be a substantial rather than a passing occurrence.

Introduction to the Conception of Combustion Process Onboard Monitoring System

2014 ◽  
Vol 214 ◽  
pp. 83-93
Author(s):  
Andrzej Bieniek
Keyword(s):  
Monitoring System ◽  
Pressure Sensor ◽  
Rotational Speed ◽  
Fuel Injection ◽  
Combustion Engine ◽  
Combustion Process ◽  
Injection System ◽  
Fuel Injection System ◽  
Speed Sensor ◽  
Future Potential

This paper presents a conception of a system designed for monitoring combustion process in a multi-cylinder combustion engine. The proposed system is based on the application of a pressure sensor installed in one of the engine’s cylinders. The analysis of the combustion process in the remaining cylinders is possible as a result of analyzing the course of the rotational speed by means of a sensor with a large resolution integrated with engine control phase sensor. This paper presents results of the initial testing of its operation and results of research into a system named CPMOS (Combustion Process Onboard Monitoring System) dedicated to a self-ignition engine of an off-highway vehicle. The use of an algorithm which applies a synthesis of a pressure sensor signal and rotational speed sensor offers the possibility of gaining a reconstructed course of pressure in all cylinders in the engine. The proposed measurement of pressure in a cylinder not involving fuel injection system can provide more detailed information regarding the course of the combustion process in the particular cylinders. The proposed concept of the CPMOS system leads to a decrease in the overall system cost as a result of the application of a single pressure sensor in a single cylinder. The future potential application of the monitoring of the combustion in each cylinder can enable the improvement of the operating parameters of the cylinders as a result of optimizing the control of the fuel injection system, EGR system and systems used for limiting exhaust gases used in the vehicle.

Development of a dual-shaft propeller thruster equipped with rotational speed sensor for UVMS control

2013 ◽  
Vol 18 (3-4) ◽  
pp. 241-247 ◽  
Author(s):  
Radzi Bin Ambar ◽  
Shinichi Sagara ◽  
Takuya Yamaguchi
Keyword(s):  
Rotational Speed ◽  
Speed Sensor

scholarly journals Self-Powered Speed Sensor for Turbodrills Based on Triboelectric Nanogenerator

Sensors ◽  
2019 ◽  
Vol 19 (22) ◽  
pp. 4889 ◽  
Author(s):  
Chuan Wu ◽  
Chenxing Fan ◽  
Guojun Wen
Keyword(s):  
Power Supply ◽  
Rotational Speed ◽  
Light Emitting Diode ◽  
Working Environment ◽  
Triboelectric Nanogenerator ◽  
Light Emitting ◽  
Speed Sensor ◽  
Laboratory Test Results ◽  
Drilling Technology ◽  
Self Powered

Turbodrills play an important role in underground energy mining. The downhole rotational speed of turbodrills is one of the key parameters for controlling the drilling technology. Therefore, it is necessary to measure the rotational speed of the turbodrills in real time. However, there is no dedicated speed sensor for the working environment of turbodrills at present. Therefore, based on the working principle of triboelectric nanogenerator (TENG), a self-powered speed sensor which can measure the speed of the turbodrills is proposed in this study. Besides, since the sensor is self-powered, it can operate without power supply. According to the laboratory test results, the measurement error of the sensor is less than 5%. In addition, the self-powered performance of the sensor was also explored in this study. The test shows that the maximum generating voltage of the sensor is about 27 V, the maximum current is about 7 μA, the maximum power is about 2 × 10−4 W, and the generated electricity can supply power for ten LED (light-emitting diode), which not only meets the power supply requirements of the sensor itself, but also makes it possible to further power other underground instruments.

scholarly journals Thermodynamic correction of particle concentrations measured by underwing probes on fast flying aircraft

2015 ◽  
Vol 8 (12) ◽  
pp. 13423-13469 ◽  
Author(s):  
R. Weigel ◽  
P. Spichtinger ◽  
C. Mahnke ◽  
M. Klingebiel ◽  
A. Afchine ◽  
...  
Keyword(s):  
Particle Concentration ◽  
Sample Volume ◽  
Ambient Conditions ◽  
Speed Sensor ◽  
Particle Penetration ◽  
Research Aircraft ◽  
Air Sample ◽  
Air Speed ◽  
Particle Imaging ◽  
Measured Particle

Abstract. Particle concentration measurements with underwing probes on aircraft are impacted by air compression upstream of the instrument body as a function of flight velocity. In particular for fast-flying aircraft the necessity arises to account for compression of the air sample volume. Hence, a correction procedure is needed to invert measured particle number concentrations to ambient conditions that is commonly applicable for different instruments to gain comparable results. In the compression region where the detection of particles occurs (i.e. under factual measurement conditions), pressure and temperature of the air sample are increased compared to ambient (undisturbed) conditions in certain distance away from the aircraft. Conventional procedures for scaling the measured number densities to ambient conditions presume that the particle penetration speed through the instruments' detection area equals the aircraft speed (True Air Speed, TAS). However, particle imaging instruments equipped with pitot-tubes measuring the Probe Air Speed (PAS) of each underwing probe reveal PAS values systematically below those of the TAS. We conclude that the deviation between PAS and TAS is mainly caused by the compression of the probed air sample. From measurements during two missions in 2014 with the German Gulfstream G-550 (HALO – High Altitude LOng range) research aircraft we develop a procedure to correct the measured particle concentration to ambient conditions using a thermodynamic approach. With the provided equation the corresponding concentration correction factor ξ is applicable to the high frequency measurements of each underwing probe which is equipped with its own air speed sensor (e.g. a pitot-tube). ξ-values of 1 to 0.85 are calculated for air speeds (i.e. TAS) between 60 and 260 m s−1. From HALO data it is found that ξ does not significantly vary between the different deployed instruments. Thus, for the current HALO underwing probe configuration a parameterisation of ξ as a function of TAS is provided for instances if PAS measurements are lacking. The ξ-correction yields higher ambient particle concentration by about 15–25 % compared to conventional procedures – an improvement which can be considered as significant for many research applications. The calculated ξ-values are specifically related to the considered HALO underwing probe arrangement and may differ for other aircraft or instrument geometries. Moreover, the ξ-correction may not cover all impacts originating from high flight velocities and from interferences between the instruments and, e.g., the aircraft wings and/or fuselage. Consequently, it is important that PAS (as a function of TAS) is individually measured by each probe deployed underneath the wings of a fast-flying aircraft.

Rotational speed sensor based on the magnetoelectric effect of composite FeSiB/Pb(Zr,Ti)O3

2021 ◽  
Vol 92 (9) ◽  
pp. 095009
Author(s):  
Xueling Jiang ◽  
Linfeng Li ◽  
Caijiang Lu ◽  
Renren Zhu ◽  
Qiang Hua ◽  
...  
Keyword(s):  
Rotational Speed ◽  
Magnetoelectric Effect ◽  
Speed Sensor
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