A method for air flow measurement using high frequency vibrations

Air flow measurements are very important in technological processes. A new air flow measurement method is proposed. The method is based on the interaction of air flow with the end of a fiber waveguide located in the flow. As the result of this interaction, random high frequency vibrations are generated in the fiber waveguide. The stochastic transducers are created for the realization of this method. The stochastic transducer consists of the fiber waveguide, the piezoceramic element and the preamplifie

Estimation of surface roughness using high frequency vibrations

Surface roughness is an important parameter for evaluating the quality of material surfaces. It affects the tribological and optical properties of the materials. The paper proposes a new method for estimation of surface roughness, which is based on measurement of high frequency vibrations that are generated when air flow interacts with the surface of a solid body. It was determined that intensity of high frequency vibrations depends on surface roughness. Sandpapers with different magnitudes of surface roughness were used for the experimental stud

Dynamic compensation of rotating blades imbalance

The purpose of this paper is to research an effect of factors that are creating an imbalance of fan rotating blades and to estimate the possibility of compensation for this parasitic effect. For this purpose the measurement system including hardware and software was developed. Measurements of vibrations and dynamic pressure of rotating two-blades fan, blades profile and lift force parameters at various rotation speed were performed. This paper presents compensation possibilities when mechanical and aerodynamic imbalance occurs

Analysis of fastening element impact on pipe modal vibrations

One of the approaches for noise reduction in pipeline transport systems lies in the selection of appropriate fasteners. Therefore, it is important to know how different pipe holders change vibrational behavior of the pipe. This paper investigates the influence of clamping elements on modal vibrations of the pipe. A measurement method is proposed for determination of the damping factor that appears due to the insertion of a pipe holder

Application of free vibration technique for evaluation of vibro-isolation properties of pipe fixing elements

One approach for reducing noises in pipeline transport systems is selection of appropriate fasteners. Therefore, it is important to know vibro-acoustic characteristics of the fastening elements. This paper proposes a measurement system for determination of dynamic properties of pipe fastening elements and describes performed experiments that demonstrate characteristics dependence on clamping force, construction of the holder and its vibration mode

Measurement system for analysis of autogyro rotor imbalance

This paper presents the measurement system that is designed for measurement and analysis of mechanical and aerodynamic unbalance. These types of unbalance occurs in mechanical systems composed of high radius blades, including rotorcrafts – autogyro. This work presents structure of the measurement system, processing and visualization process of measurement data

A method for air flow measurement using high frequency vibrations

Air flow measurements are very important in technological processes. A new air flow measurement method is proposed. The method is based on the interaction of air flow with the end of a fiber waveguide located in the flow. As the result of this interaction, random high frequency vibrations are generated in the fiber waveguide. The stochastic transducers are created for the realization of this method. The stochastic transducer consists of the fiber waveguide, the piezoceramic element and the preamplifie

A method for air flow measurement using high frequency vibrations

Air flow measurements are very important in technological processes. A new air flow measurement method is proposed. The method is based on the interaction of air flow with the end of a fiber waveguide located in the flow. As the result of this interaction, random high frequency vibrations are generated in the fiber waveguide. The stochastic transducers are created for the realization of this method. The stochastic transducer consists of the fiber waveguide, the piezoceramic element and the preamplifie