Теория исследования температурного поля биотоплива нового термоанемометрического расходомера с использованием алгоритмических методов, аппарата искусственных нейронных сетей

Створено нову наукову концепцію, нові методи та засоби удосконалення нового термоанемометричного витратоміра (ТАВ) (патент України), теоретичні засади дослідження температурного поля біопалива. Підвищено точність у 2 рази (до 1,5 %) у порівнянні з відомими роботами (3 %), підвищено швидкодію у 10 разів. Запропоновано для подальшого використання на практиці новий програмно-апаратний комплекс на основі ЕОМ (патент України), що забезпечує автоматизований процес вимірювань у реальному часі з одночасним документуванням інформації у потрібній формі (цифри, графіки, таблиці), що розширює функціональні можливості. Забезпечено збільшення точності розробленого ТАВ шляхом використання: запропонованої нової математичної моделі ТАВ із введеними додатковими поправками, що враховують вплив основних конструктивних параметрів приладу; запропонованих у результаті дослідження теплового потоку біопалива нових методів зменшення похибок ТАВ. Обґрунтовано вибір схеми ТАВ з ежекторним соплом. Проведено тарування ТАВ на сертифікованій установці та експериментальне визначення точнісних характеристик. Експериментально та моделюванням на ЕОМ підтверджено висновки, отримані аналітичним шляхом. Уперше отримано формули, що пов’язують температуру витрати палива на відстані від нагрівача з об’ємною витратою моторного палива за умови його ламінарної та турбулентної течії через витратомір. Уперше запропоновано застосувати процедуру лінійної апроксимації з одночасним вимірюванням температури у декількох точках потоку моторного палива для підвищення точності витратоміра. Уперше запропоновано для підвищення точності ТАВ реалізовувати обчислення об’ємної витрати моторного палива з використанням штучної нейронної мережі та нейропроцесора у складі цифрової ЕОМ (патент України).A new scientific concept, new methods and means of improving the flow of new termoanemometrychnoho (TAB) (patent of Ukraine), the theoretical bases of research of temperature field of biofuels. Increased accuracy (1.5%) compared with the known works (3%), high speed 10 times. A further practical use new software and hardware for computer-based (patent of Ukraine), which provides automated measurements in real time while documenting information in the right form (figures, graphs, tables) that extends the functionality. Provided designed to increase the accuracy by using TAB: proposed new mathematical model of TAB introduced additional amendments, taking into account the influence of the main design parameters of the device; The study proposed in biofuel heat flow of new methods to reduce errors TAB. The choice of the TAB circuit ejector nozzle. A certified calibration TAB to install and experimental determination accuracy characteristics. The experimental and computer modeling confirmed the conclusions obtained analytically. For the first time a formula linking the fuel temperature at a distance from the heater with a volume flow of motor fuel subject to laminar and turbulent flow through. For the first time invited to apply linear approximation process with simultaneous measurement of temperature in several points of the motor fuel flow to improve the accuracy of flow. For the first time proposed to improve the accuracy of calculating TAB sell motor fuel volume flow using artificial neural networks and neyroprotsesora in digital computers (patent of Ukraine).Создана новая научная концепция, новые методы и средства усовершенствования нового термоанемометрического расходомера (ТАВ) (патент Украины), теоретические основы исследования температурного поля биотоплива. Повышена точность (до 1,5%) по сравнению с известными работами (3%), повышено быстродействие в 10 раз. Предложено для дальнейшего использования на практике новый программно-аппаратный комплекс на основе ЭВМ (патент Украины), который обеспечивает автоматизированный процесс измерений в реальном времени с одновременным документированием информации в нужной форме (цифры, графики, таблицы), расширяет функциональные возможности. Обеспечено увеличение точности разработанного ТАВ путем использования: предлагаемой новой математической модели ТАВ с введенными дополнительными поправками, учитывающими влияние основных конструктивных параметров прибора; предложенных в результате исследования теплового потока биотоплива новых методов уменьшения погрешностей ТАВ. Обоснован выбор схемы ТАВ с эжекторным соплом. Проведено тарирование ТАВ на сертифицированной установке и экспериментальное определение точностных характеристик. Экспериментально и моделированием на ЭВМ подтверждены выводы, полученные аналитическим путем. Впервые получены формулы, связывающие температуру расхода топлива на расстоянии от нагревателя с объемным расходом моторного топлива при его ламинарном и турбулентном течении через расходомер. Впервые предложено применить процедуру линейной аппроксимации с одновременным измерением температуры в нескольких точках потока моторного топлива для повышения точности расходомера. Впервые предложено для повышения точности ТАВ реализовывать вычисления объемного расхода моторного топлива с использованием искусственной нейронной сети и нейропроцессора в составе цифровой ЭВМ (патент Украины)

Guidewire-mounted thermal sensors to assess coronary hemodynamics

The vessels of the coronary circulation are prone to arteriosclerotic disease, which can lead to the development of obstructions to blood flow. The conventional way to diagnose the severity of this type of disease is by coronary angiography. This method, however, only provides insight into the morphology of the coronary vessels, whereas for an accurate diagnosis a measure for the actual flow impediment is needed. To perform these measurements, sensor-tipped guidewires have been developed to measure intra-coronary pressure and blood flow velocity. Diagnosis of coronary disease based on the time-average of these measurements have been shown to improve the clinical outcome of treatment significantly. However, since the coronary vessels are embedded in the (contracting) cardiac muscle, the interpretation of these indices is complicated and can be improved by simultaneously assessing the dynamics of coronary pressure and flow. The research described in this thesis therefore focusses on the one hand on developing devices for the simultaneous assessment of coronary pressure and flow dynamics and on the other hand on modeling the heart and coronary vessels to support the interpretation of these dynamic measurements. In the development of a device which can measure both coronary pressure and flow, two different strategies have been chosen. In the first strategy, a method has been developed to operate an already clinically used pressure sensor-tipped guidewire (pressure wire) as a thermal anemometer to also measure flow. In an in-vitro model it has been demonstrated that the power required to electrically heat the sensor is a measure for the shear rate at the sensor surface and that the method can be used to assess coronary flow reserve (CFR). By slightly adapting the method and combining it with a continuous thermodilution method, it has also been shown that the dynamics of both pressure and volumetric flow can be measured simultaneously in physiological representative in-vitro and ex-vivo experiments. The main drawbacks of this thermal method with a pressure wire are the relatively high sensor temperature required and the inability to detect flow reversal. In the second strategy, a new flow sensor, embedded in a flexible polyimide chip, has been specially designed to be mounted on a guidewire. The flow sensing element consists of a heater, operated at constant power, and thermocouples measuring the temperature difference up- and downstream from the heater. To gain insight into the working principle and the importance of the different design parameters, an analytical model has been developed. Experiments where upscaled sensors have been subjected to steady and pulsatile flow, indicate that the model is able to reproduce the experimental results fairly well but that the sensitivity to shear rate is rather limited in the physiological range. This sensitivity to shear rate can possibly be improved by operating the heater at constant temperature, which has been investigated with invitro experiments with upscaled sensors and a finite element analysis of the real, small size sensor. These studies have demonstrated that constant temperature operation of the heater is beneficial over constant power operation and that the dynamics of physiological coronary shear rate, including retrograde flow, can be assessed at an overheat temperature of only 5 K. From these characterization studies a new design of the sensor has been proposed, which is currently being manufactured to be tested in both in-vitro and ex-vivo experiments. To support the interpretation of the dynamic pressure and flow measurements, a numerical model of the heart and coronary circulation has been developed. The model is based on the coupling of four interacting parts: A model for the left ventricle which is based on the mechanics of a single myofiber, a 1D wave propagation model for the large epicardial coronary arteries, a stenosis element, and a Windkessel representation of the coronary micro-vessels. Comparison of the results obtained with the model with experimental observations described in literature has shown that the model is able to simulate the effect of different types of disease on coronary hemodynamics. After further validation, the model can be used as a tool to study the effect of combinations of epicardial and/or microcirculatory disease on pressure- and flow-based indices. To model the relation between the pressure and flow waves in the coronary arteries correctly, as well as to assist in the decision-making regarding the mechanical treatment of coronary stenoses, the mechanical behaviour of the coronary arterial wall is required. Therefore, a mixed numerical-experimental method has been employed to fit a micro-structurally based constitutive model to in-situ extensioninflation experiments on porcine coronary arteries. It has been demonstrated that the model can accurately describe the experimental data and, additionally, it has been found that the most influential parameter, describing the collagen fiber orientation, can be considered constant at physiological loading. In further research, this can be used to tackle over-parameterization issues inherent to fitting similar constitutive models to data obtained in a clinical setting. In this thesis, a computational model of the coronary circulation is presented and methods for simultaneous pressure and flow assessment are introduced. By operating an already clinically used pressure wire as a thermal anemometer, a methodology was developed which is close to clinical application, while a new sensor was designed to be more accurate in different flow conditions

Remote control of nonlinear motion for mechatronic machine by means of CoDeSys compatible industrial controller

Navedeni članak opisuje hardversko-softverski kompleks čiji je cilj naučiti studente kako daljinski upravljati mehatroničkim mehanizmima putem standardne industrijske automatizacije. Svrha ovoga rada je razmotriti sljedeće probleme: upravljački algoritam gibanja zakrivljenom putanjom, odgovarajući razvoj softvera za industrijske regulatore koji koriste CoDeSys okruženje, primjenu CoDeSys programskog paketa za razvoj interaktivnih HTML-aplikacija s web-sučeljem.The given article describes the hardware-software complex aimed to teach students how to control the mechatronic mechanisms remotely by means of standard industrial automation. The purpose of this paper is to consider the following problems: the curved trajectory movement algorithm control, the corresponding software development for the industrial controllers using CoDeSys environment, CoDeSys software package usage for the development of interactive HTML-applications with WEB-interface

Aeronautical Engineering. A continuing bibliography, supplement 112

This bibliography lists 424 reports, articles, and other documents introduced into the NASA scientific and technical information system in July 1979

3D Structuration Techniques of LTCC for Microsystems Applications

This thesis aimed at developing new 3D structuration techniques for a relatively recent new ceramic technology called LTCC, which stands for Low Temperature, Co-fired Ceramic. It is a material originally developed for the microelectronic packaging industry; its chemical and thermal stabilities make it suitable to military-grade and automotive applications, such as car ignition systems and Wi-Fi antennae (GHz frequencies). In recent years however, the research in ceramic microsystems has seen a growing interest for microfluidics, packaging, MEMS and sensors. Positioned at the crossing of classical thick-film technology on alumina substrate and of high temperature ceramics, this new kind of easily structurable ceramic is filling the technological and dimensional gap between microsystems in Silicon and classical "macro microsystems", in the sense that we can now structure microdevices in the range from 150 mm to 150 mm. In effect, LTCC technology allows printing conductors and other inks from 30 mm to many mm, structuration from 150 mm to 150 mm, and suspended structures with gaps down to 30 mm thanks to sacrificial materials. Sensors and their packaging are now merged in what we can call "functional packaging". The contributions of this thesis lie both in the technological aspects we brought, and in the innovative microfluidic sensors and devices created using our developed methods. These realizations would not have been possible with the standard lamination and firing techniques used so far. Hence, we allow circumventing the problems related to microfluidics circuitry: for instance, the difficulty to control final fired dimensions, the burden to produce cavities or open structures and the associated delaminations of tapes, and the absence of "recipe" for the industrialization of fluidic devices. The achievements of the presented research can be summarized as follows: The control of final dimensions is mastered after having studied the influence of lamination parameters, proving they have a considerable impact. It is now possible to have a set of design rules for a given material, deviating from suppliers' recommendations for the manufacture of slender structures requiring reduced lamination. A new lamination method was set up, permitting the assembly of complex microfluidic circuits that would normally not sustain standard lamination. The method is based on partial pseudo-isostatic sub-laminations, with the help of a constrained rubber, subsequently consolidated together with a final standard uniaxial lamination. The conflict between well bonded tapes and acceptable output geometry is greatly attenuated. We achieved the formulation of a new class of Sacrificial Volume Materials (SVM) to allow the fabrication of open structures on LTCC and on standard alumina substrates; these are indeed screen-printable inks made by mixing together mineral compounds, a glassy phase and experimental organic binders. This is an appreciable improvement over the so-far existing SVMs for LTCC, limited to closed structures such as thin membranes. An innovative industrial-grade potentially low-cost diagnostics multisensor for the pneumatic industry was developed, allowing the measurement of compressed air pressure, flow and temperature. The device is entirely mounted by soldering onto an electro-fluidic platform, de facto making it a true electro-fluidic SMD component in itself. It comprises additionally its own integrated SMD electronics, and thanks to standard hybrid assembly techniques, gets rid of external wires and tubings – this prowess was never achieved before. This opens the way for in situ diagnostics of industrial systems through the use of low-cost integrated sensors that directly output conditioned signals. In addition to the abovementioned developments, we propose an extensive review of existing Sacrificial Volume Materials, and we present numerous applications of LTCC to sensors and microsystems, such as capacitive microforce sensors, a chemical microreactor and microthrusters. In conclusion, LTCC is a technology adapted to the industrial production of microfluidic sensors and devices: the fabrication steps are all industrializable, with an easy transition from prototyping to mass production. Nonetheless, the structuration of channels, cavities and membranes obey complex rules; it is for the moment not yet possible to choose with accuracy the right manufacturing parameters without testing. Consequently, thorough engineering and mastering of the know-how of the whole manufacturing process is still necessary to produce efficient LTCC electro-fluidic circuits, in contrast with older techniques such as classical thick-film technology on alumina substrates or PCBs in FR-4. Notwithstanding its lack of maturity, the still young LTCC technology is promising in both the microelectronics and microfluidics domains. Engineers have a better understanding of the structuration possibilities, of the implications of lamination, and of the most common problems; they have now all the tools in hand to create complex microfluidics circuits

Тези доповідей VIII Міжнародної науково-технічної конференції «Інформаційно-комп’ютерні технології – 2016»

Представлено доповіді учасників Міжнародної науково-технічної конференції «Інформаційно-комп’ютерні техно-логії 2016». Наведено аналіз та результати досліджень су-часних проблем комп'ютерно-інформаційних технологій, систем керування, автоматизації, радіотехніки, телеко-мунікацій, біотехнічних апаратів та цифрової обробки сиг-налів, використання інформаційно-комп’ютерних техноло-гій в освіті

Gas Flow measurement

Tato bakalářská práce je zaměřena na problematiku tepelných snímačů průtoku. Jsou zde krátce popsány základní vlastnosti proudící tekutiny a základní pojmy v oboru měření průtoku a možnosti jeho měření. Podrobněji je zde popsán princip funkce tepelných snímačů průtoku a jejich provedení. Dále byla s čidly FS2 a FS7 od firmy IST AG provedena série měření. V měření byly zjištěny požadavky na napájení, časové konstanty a série měření za účelem určení matematického modelu čidel. Matematické modely byly sestaveny různými způsoby a byla zjištěna jejich závislost na teplotě. Díky měření bylo možné navrhnout univerzální elektronický obvod řízený mikrokontrolerem Arduino Mega 2560. Mikrokontroler provozuje snímač v režimu konstantního rozdílu teplot. S navrženou elektronikou byla provedena kontrolní ověřovací měření a bylo ověřeno potlačení parazitního vlivu teploty.This bachelor's thesis is focussed on thermal flow meters. There are shortly described basic characteristics of flow and basic terms in flow measurement and its opportunities. The principles of operation of thermal flow meters and its implementation is described closely. With sensors developed by the company of IST AG called FS2 and FS7 was done series of measurements, like measurement of time responses, supply demands, and measurements in the view of determining of mathematical models of the sensors. Mathematical models were determined in a few different ways and its dependence on ambient temperature was found. Thanks to measurement were designed universal electric circuit controlled by microcontroller Arduino Mega 2560. Microcontroller keeps sensors in constant temperature difference mode. There were made trial measurements with designed electronics and the suppression of temperature was checked.

Thermoelectric magnetohydrodynamics

The effect of the interaction of steady uniform transverse magnetic fields with the thermoelectic current in liquid metals that might exist at the nonisothermal, electically conducting interface of the metal liners, termed as TEMHD hereafter, is the subject of some theoretical and extensive experimental investigation reported in this thesis. The investigation has primarily been motivated by the possibility of significant consequences of such an effect in the lithium blankets of magnetically confined thermonuclear reactors (TNR) and the lack of any previous serious attempt to investigate this interaction experimentally. It is shown theoretically that at high Hartmann numbers (M) in various TEMHD configurations, the flow is equivalent to the ordinary MHD flow with an inherent pressure gradient due to the thermoelectric current and magnetic field, B. How well the TEMHD interaction is effective is measured in terms of a new nondimensional number D, the ratio of thermoelectric e.m.f. and the motion (determined by viscous and inherent force balance) induced e.m.f.. Theoretical analysis for the secondary flow due to buoyancy in simple configurations shows that the secondary flow is at least an order of magnitude lower than the corresponding TEMHD flow. However, for other complex configurations there exists a B , a function of Rayleigh and Prandti numbers, in order to ignore the buoyancy effect. The experimental results obtained with Hg in Cu channels, as reported in this thesis, show that even in laboratory model experiments this TEMHD interaction in liquid metals in metal containers with non-isothermal interface does produce a significant body force. This body force is measurable in terms*of either the fluid flow velocity (stirring) or the static pressure gradient if the fluid flow is suitably constrained. It has been shown that these measurements provide a new method of finding experimentally the thermopower of liquid metals in magnetic fields as accurately as in conventional methods if the configuration is rightly chosen. These measurements are sensitive enough to the presence of traces of impurity to serve the purpose of determining the degree of refinement in metallurgical processes. Since lithium has an absolute thermopower, ignoring the sign, four times that of Hg, the scaling up of the TEMHD performance in Hg-Cu combination gives an adequate simulation of the blanket system TEMHD .With the complex geometry of TNR and the magnetic field system therein, the TEMHD configurations to be considered are very varied. Initially, to avoid buoyancy driven flow, simple thermally stable stratified configurations have been adopted in the form of (i) uniform horizontal copper pipes of circular cross-section (1.25 and 2.54 cm in diameter) with a sinusoidal (first harmonic) peripheral temperature distribution, and (ii) horizontal straight copper pipe with a rectangular cross-section (2i 2.5 cm square) with insulated sidewall interfaces and heated from the top and cooled at the bottom. Apart from the static pressure difference and velocity measurements, temperature oscillations are reported even in these basic thermally stable configurations which are suppressed at some field strength,B cr. For a fixed heat transfer,- the temperature in the TEMHD system has been found to drop with increase in B. These two unexpected experimental observations have been tentatively explained on the basis of finite amplitude instability due to magnetic-buoyancy force driven relaxation of isotherm curvature. In order to investigate TEMHD flow without pressure gradient, experimental investigations in (endless) annular channels with the top surface free, heated and cooled at the vertical sidewalls in uniform steady axial magnetic fields have been performed for mixed and totally conducting solid-liquid interfaces. Since in this configuration the buoyancy effect is inherently present, a few measurements of secondary flow and free surface profile are presented along with velocity and temperature measurements. The temperature at the hot wall increases with B as is normally expected, due to suppression of buoyancy induced vorticity by B. The critical magnetic field for transverse vorticity suppression and the build-up of magnetic drag by boundary layer formation has been found to occur at distinctly different values. By the choice of suitable nonlinear heating and mixed conducting interfaces, it has been shown that free shear layers could be generated. This experiment also confirms the possibility of higher TEMHD velocity as a function of B for aligned temperature gradient and B, as predicted by theoretical analysis. A discussion on the vorticity and stationary and drifting wave motion, as has been observed in these experiments, is provided. A simple novel structure of the lithium blanket of the TOKAMAK type of TNR in the form of double spiral modules is suggested to exploit TEMHD effect to pump lithium for heat transfer purpose. Limited experimental results that could be obtained on a laboratory model, with Hg as the fluid and the module fabricated with Cu are presented. The experimental measurements have been conducted with inclined tube manometers, flowmeters, mechanical veined vorticity-velocity probes, pitot tube • and thermoelectric potential probes. The thermoelectric potential probes, which have been iinverted as a modification of the ordinary potential probes to suit the TEMHD environment, provide simultaneous measurement of temperature and velocity at B > Bcr and the calibration procedure is much easier than for the alternative methods of measurement. A chapter on the review of literature relevant to TEMHD is provided to serve as a background of the investigation reported here, and a few areas of further investigation in TEMHD are suggested