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With the growth of the population in the world, energy problem has become a major topic in the world. Energy conservation has become an important part of China's national development strategy. The use of microwave heating instead of traditional heating can greatly improve the utilization rate of energy, and then achieve the goal of energy conservation and emissions reduction. However, due to the uneven...
In the design of ultrasonic ranging system, MCS51 singleship is used as the core component of the hardware system and the control software is used. The software is designed with advanced microcontroller programming language. Closed loop control is used to adjust the amplitude of received signal and to extract the ultrasonic propagation time. The double closed loop control technique of amplitude and...
To estimate the mass emissions of combustion sources, the accurate determination of the exhaust mass flow with reasonable time resolution is a key requirement. State of the art flowmeters are often based on the measurement of the time of flight of ultrasonic bursts. Such systems are not well suited for harsh environment due to the fact that they expose their sensitive Piezo-transceiver directly to...
In this survey, in order to examine the viscous heating effect of thermocouples, temperature rise due to excitation of a HIFU transducer has been measured by using two different types of T-type thermocouples embedded inside the Tissue Mimicking Material (TMM). In order to obtain the temperature values from the thermocouples more effectively, a PC-based multi-channel data acquisition and monitoring...
The article is devoted to the study of the existing methods and solutions of non-intrusive methods for flow parameters measurement. The literature sources with various types of measurement instruments used to measure the flow parameters were studied and reviewed. The theoretical materials on non-intrusive methods and device implementation examples are presented. The method for combination of the measurement...
This paper gives a method of ultrasonic heat meter design. Heat is calculated by measuring the flow and temperature of the water in pipe. Firstly, principle of ultrasonic is adopted to measure the flow of water in this project. Then, water temperature is measured by the temperature sensor in pairs of inlet and outlet. Finally, heat released through the heat exchange system is calculated by MCU. Inlet...
Ultrasonic thermometry is a kind of emerging acoustic pyrometry technology, and it can break through the limitation of various electromagnetic environment, where the traditional temperature measurement methods have failed to operate satisfactorily. The temperature on the current path can be retrieved by the speed of the ultrasonic wave. When the measurement path is fixed, the key issue of ultrasonic...
This paper presents an ultrasonic thermometry state of the art study and shows principle of the ultrasonic thermometry through experiments with an ultrasonic thermometer prototype. The study covers a brief ultrasonic temperature measurement research history and focuses on recent revelations in this field. The thermometer prototype is constructed to be portable and usable for educational presentations...
In this paper, we find conditions that reconstruction of temperature distribution gets worse when the ultrasonic transceivers (transmitter and receiver) are arranged flexibly. We discovered the minimum number of the ultrasonic transceivers required for successful reconstruction and proved that the number is correct. Moreover, we proposed arrangement of the number in accordance with parity of pixel...
In many industrial technological processes, liquids are subjected to high pressures, e.g., in the high pressure food preservation. Similarly, in modern fuel injection systems for diesel engines, biofuel is subjected to a pressure up to 300 MPa. In such conditions, in liquids, high-pressure phase transitions (solidification) can occur that substantially increase the density and liquid viscosity. This...
In many industrial technological processes, liquids are subjected to high pressures, e.g., in the high pressure food preservation. Similarly, in modern fuel injection systems for diesel engines, biofuel is subjected to a pressure up to 300 MPa. In such conditions, in liquids, phase transitions can occur that substantially increase the density and liquid viscosity. This can be very detrimental for...
Accurate measurement of acoustic dispersion has important applications in theoretical acoustics, ultrasound tissue characterization, ultrasound measurement systems, etc. Usually, the parameter of interest associated to dispersion is the variation in the propagation velocity as a function of the frequency or the temperature. Nevertheless, this work is focused on the study of the variation in the propagation...
This paper presents an efficient method to measure physical parameters of thin elastic layers by using an air-coupled ultrasound technique. In the method, surface densities of elastic thin layers are approximated through solely non-contact measurement of through-transmission of ultrasonic signals. A copper foil and a copper foil coated with carbon composite on both sides are used to experimentally...
Nonlinear ultrasonic measurements has been proposed to characterize the creep damage evolution of P92 martensitic ferritic steels at a temperature of 650 °C and stresses of 100 MPa and 115 MPa, respectively. The correlation of increase-decrease-increase between the ultrasonic nonlinearity and the creep strain was achieved for both sets of specimens. Considering the metallographic studies, nonlinear...
The testing guideline of medical measuring devices on ultrasonic physiotherapy equipment is published in Thailand, which is conducted under a collaborative project between the ultrasound laboratory of the National Institute of Metrology, Thailand (NIMT) and the department of medical sciences, and the department of health service support, ministry of public health. This project has been carried out...
The presence of water in lubricating oil is destructive even in very small quantities. The ultrasonic measurement is an alternative method to find a solutions for detecting and measuring the water contamination in the lubricant oil. The amount of water contamination in lubricating oil will affect the velocity of wave propagation in the lubricant. In this study, a 2.25 MHz ultrasonic wave is propagated...
This paper presents some considerations about uncertainty and noise related to ultrasonic transducers in time of flight estimation for wind speed measurement with pulsed transmission mode. Experimental results show the noise distribution in a measurement setup using ultrasonic transducers and the relation between signal to noise ratio, uncertainties and number of cycles used in pulsed transmission...
A lot of research in security of cyber physical systems focus on threat models where an attacker can spoof sensor readings by compromising the communication channel. A little focus is given to attacks on physical components. In this paper a method to detect potential attacks on physical components in a Cyber Physical System (CPS) is proposed. Physical attacks are detected through a comparison of noise...
The article presents a hardware and software complex for the automated measurement of the pallet dimensions and defining of foreign bodies on the pallet surface. The block diagram of the system and the software are described. Methods to improve the accuracy of measurement of the geometric dimensions of the pallet are briefly described: temperature correction of the velocity of propagation of ultrasonic...
The article describes the ultrasonic level gauge of light oil. The principle of error compensation caused by instability of propagation conditions due to the presence of a temperature gradient and density along the propagation path of an ultrasonic wave is presented. The acoustic path of the level gauge is described and includes three channels: a measuring channel, a reference channel and a channel...
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