Embedded supervisory control and output reporting for the oscillating ultrasonic temperature sensors

Ultrasonic temperature sensors can potentially outperform conven-tional sensors because they are capable of very fast sensing across the complete ultrasound pathway, whilst conventional sensors only sense temperature at a single point and have substantial thermal inertia. We report recent develop-ments in electronic instrumentation for oscillating ultrasonic temperature sen-sors with the aim of achieving high accuracy and low scatter at a low cost

Experimental evaluation of ultrasonic oscillating temperature sensors (UOTS) under cyclically changing temperatures

In contrast to most conventional temperature sensors, which need to come to thermal equilibrium with the medium of interest to report its temperature, UOTS interrogate the medium based on the propagation speed of ultrasound, and will return temperature data that are “averaged” for the complete ultrasound pathway. It has been demonstrated that UOTS can provide consistent high-resolution temperature readings under steadily decreasing temperatures using inexpensive ultrasonic transducers and low cost electronic instrumentation

Comparison of the responsiveness of ultrasonic oscillating temperature sensors (UOTSes) and conventional sensors to temperature inflection points

Ultrasonic oscillating temperature sensors (UOTSes), in distinction to conventional temperature sensors, feature almost negligible settling time. This property can be useful for detecting malfunctions, failures and misuses of heat exchangers. However, most exchangers handle substantial thermal masses, which obscure the detection of any temperature changes. We compared the responsiveness of conventional DS18B20 sensors and an UOTS to the change in the temperature gradient of over 3.5 kg of water using a posteriori records. Temperature inflection points were estimated by extending the curves for separate distinct heating and cooling intervals that fit best and finding their interception. For the UOTS, the interception occurred about 100 seconds sooner, making it a potential candidate for detecting heat exchangers’ irregularities

Accurate heat loss evaluation of water-cooled electric motors using a differential ultrasonic calorimeter

Measuring thermal losses of electric motors are important for their design optimization and correct pricing after manufacture. This measurement can be conducted by measuring the temperature difference of the motor coolant (commonly water) between the coolant's inlet and outlet. High speed of measurement facilitates testing various load scenarios and manufacture throughput; high measurement accuracy and resolution enables correct conclusions on efficiency of various design alterations and price bracketing of manufactured pieces. Ultrasonic temperature sensors can fast sense temperature with high resolution and accuracy across the complete ultrasonic pathway. Conventional high resolution ultrasonic sensors are expensive; however, oscillating ultrasonic temperature sensors can be implemented using mass produced transducers and electronic parts which cost a fraction of the price of conventional high resolution ultrasonic measurement equipment. The presented ongoing research focuses on development of a differential ultrasonic oscillating temperature sensor for evaluation of power losses in electrical motors. Computer simulations, electronic and firmware design, and experimental results are presented and discussed

Comparison of the responsiveness of ultrasonic oscillating temperature sensors (UOTSes) and conventional sensors to temperature inflection

Ultrasonic oscillating temperature sensors (UOTSes), in distinction to conventional temperature sensors, feature almost negligible settling time. This property can be useful for detecting malfunctions, failures and misuses of heat exchangers. However, most exchangers handle substantial thermal masses, which obscure the detection of any temperature changes. We compared the responsiveness of conventional DS18B20 sensors and an UOTS to the change in the temperature gradient of over 3.5 kg of water using a posteriori records. Temperature inflection points were estimated by extending the curves for separate distinct heating and cooling intervals that fit best and finding their interception. For the UOTS, the interception occurred about 100 seconds sooner, making it a potential candidate for detecting heat exchangers’ irregularities

Ultrasonic oscillating temperature sensor for operation in air

Ultrasonic oscillating temperature sensors (UOTSes) allow sensing temperatures of the medium of interest across the complete ultrasonic pathway and quickly react to the temperature changes. These features are advantageous comparing to the conventional temperature sensors, which need to come to the thermal equilibrium to the environment in order to report the correct temperature, and sense temperature at a particular point only. To date UOTSes were used for temperature measurements in liquids only. In its simplest form an UOTS requires a pair of ultrasonic transducers and an amplifier, that feeds the signal from the receiver to the transmitter. Positive feedback leads to sustained oscillations with the frequency, which is dependent on the temperature distribution between the transducers as it determines the ultrasound velocity thus the ultrasound propagation delay. For the reporting protype we used a pair of narrowband 40 kHz ultrasonic transducers and an electronic driver built around a dual operating amplifier (opamp) LM358. The transducers were mounted on an aluminium 2020 slot 5 profile using two rubber lined Munsen rings with backplates and positioned at desirable distances with the help of four roll-in T-nuts. One opamp provided the mid supply reference point, and the other operated as an inverting amplifier with the gain ranging within 10..50. Increasing the distance between the transducers required increasing the gain to sustain the oscillations. When the distance changed, resulting in the change in the propagation delay, the output frequency of the UOTS changed too, confirming the feasibility of measuring air temperature using UOTSes. The frequency changed substantially when the air between the transducers was heated using a hairdryer. We present details of the mechanical and electronic design of the working prototype and discuss the obtained experimental results

Using Ultrasonic Oscillating Temperature Sensors (UOTSes) to Measure Aggregate temperatures in Liquid and Gaseous Media

An ultrasonic oscillating temperature sensor (UOTS) features a pair of ultrasonic transducers and an amplifier, which compensates for the energy losses in the signal pathway. An UOTS oscillates with frequency, which is related to the ultrasound velocity in the medium between the transducers, which, in turn, depends on the medium’s temperature. In this paper, we discuss our past experiments with UOTSs in aqueous media and the initial results of a feasibility study on the use of an UOTS in air

Advanced Information Systems and Technologies

This book comprises the proceedings of the V International Scientific Conference "Advanced Information Systems and Technologies, AIST-2017". The proceeding papers cover issues related to system analysis and modeling, project management, information system engineering, intelligent data processing computer networking and telecomunications. They will be useful for students, graduate students, researchers who interested in computer science

Advanced Information Systems and Technologies

This book comprises the proceedings of the V International Scientific Conference "Advanced Information Systems and Technologies, AIST-2017". The proceeding papers cover issues related to system analysis and modeling, project management, information system engineering, intelligent data processing computer networking and telecomunications. They will be useful for students, graduate students, researchers who interested in computer science