Measurement of Transient Fluid Temperature in the Heat Exchangers

In the chapter, a method for measuring the transient temperature of the flowing fluid based on time temperature changes of the thermometer is described. In the presented method, the thermometer is considered as an inertial system of first and second order. To reduce the influence of random errors in the temperature measurement, the local polynomial approximation based on nine points is used. As a result, the first and second derivatives of a temperature, which indicate how the temperature of the thermometer varies over time, are determined very accurately. Next, the time constant is defined as a function of fluid velocity for sheathed thermocouples with different diameters. The applicability of the presented method is demonstrated on real data in the experiment. The air temperature is estimated from measurements carried out by the three thermocouples having different outer diameters when the air velocity varied in time. A comparison of the computed temperatures of air gives confidence to the accuracy of the presented method. The method presented in this chapter for measuring the transient temperature of the fluid can be used for the online monitoring of fluid temperature change with time

Determination of transient temperature fields in thick-walled elements using the inverse method

The purpose of this paper is to propose a method of determining the transient temperature of the inner surface of thick-walled elements. The method can be used to determine thermal stresses in pressure elements. An inverse marching method is proposed to determine the transient temperature of the thickwalled element inner surface with high accuracy. The inverse method was validated computationally. The comparison between the temperatures obtained from the direct heat conduction problem solution and the results obtained by means of the proposed inverse method is very satisfactory. The advantage of the method is the possibility of determining the heat transfer coefficient at a point on the exposed surface based on the local temperature distribution measured on the insulated outer surface. The heat transfer coefficient determined experimentally can be used to calculate thermal stresses in elements with a complex shape. The proposed method can be used in online computer systems to monitor temperature and thermal stresses in thick-walled pressure components because the computing time is very short

Determination of transient fluid temperature using the inverse method

This paper proposes an inverse method to obtain accurate measurements of the transient temperature of fluid. A method for unit step and linear rise of temperature is presented. For this purpose, the thermometer housing is modelled as a full cylindrical element (with no inner hole), divided into four control volumes. Using the control volume method, the heat balance equations can be written for each of the nodes for each of the control volumes. Thus, for a known temperature in the middle of the cylindrical element, the distribution of temperature in three nodes and heat flux at the outer surface were obtained. For a known value of the heat transfer coefficient the temperature of the fluid can be calculated using the boundary condition. Additionally, results of experimental research are presented. The research was carried out during the start-up of an experimental installation, which comprises: a steam generator unit, an installation for boiler feed water treatment, a tray-type deaerator, a blow down flashvessel for heat recovery, a steam pressure reduction station, a boiler control system and a steam header made of martensitic high alloy P91 steel. Based on temperature measurements made in the steam header using the inverse method, accurate measurements of the transient temperature of the steam were obtained. The results of the calculations are compared with the real temperature of the steam, which can be determined for a known pressure and enthalpy

The Role of Information Structure in the Process of Learning the Passive Voice

Der Erwerb des deutschen Passivs erfasst mehrere Teilbereiche der Grammatik, womit die Lerner/innen vor eine komplexe Aufgabe gestellt werden. Als weitere Schwierigkeit kommt hinzu, dass Passivkonstruktionen nur unter bestimmten informationsstrukturellen Bedingungen auftreten kőnnen. In der Regel dann, wenn das Subjekt des Passivsatzes (meist der Patiens) schon vorerwähnt wurde (given/bekannt) und das Objekt (meist der Agens) als new/unbekannt eingeführt wird. In Hinblick darauf, dass sich die Ausdrucksmittel zur Kodierung der Informationsstruktur in verschiedenen Sprachen nur tendenziell gleichen, kann hier angenommen werden, dass die DaF -Lernende (darunter auch die polnischen Deutschlerner/innen) nur mühsam Kontexte erkennen, in denen Passiv befördert wird. Die Prozesse der Sprachproduktion sowie der Sprachrezeption von Passivsätzen könnten jedoch durch die passivfordernden Kontexteinflüsse erleichtert werden.Learning the passive voice involves becoming acquainted with a number of partial grammatical issues, which alone makes it a complex task for native speakers but especially for foreign language learners. One other difficulty is caused by the fact that passive structures can be used only on certain conditions, that is mostly when the subject (patient) of the passive sentence is what is given and the complement (agent) appears as a new element of the sentence. In the context of foreign language learning it must be emphasized that the means for encoding information structure does not correlate (or only appears to correlate, as in Polish in relation to German) across languages. In other words, each language community has their own preferences as to how to structure discourse. It can thus be assumed that the German language learner will have difficulty recognizing and using proper information structures both in the process of understanding and producing passive sentences, and that the influence of context may play a crucial role in that process.Rola struktury informacyjnej w procesie nauczania strony biernej Opanowanie strony biernej obejmuje wiele cząstkowych zagadnień gramatycznych, co stawia użytkowników języka niemieckiego (native speakers, ale przede wszystkim obcokrajowców) przed bardzo kompleksowym zadaniem. Inną trudnością jest to, że konstrukcje bierne mogą być użyte tylko wtedy, gdy spełnione są określone warunki, tj. najczęściej wtedy, gdy podmiot zdania strony biernej (Patiens) został już wspomniany, a dopełnienie (Agens) pojawia się w zdaniu jako element nowy. W kontekście nauczania języków obcych należy podkreślić, że środki wyrazu używane do kodowania struktury informacyjnej w różnych językach nie pokrywają się lub pokrywają się tylko pozornie (tak jak między językiem niemieckim i polskim). Innymi słowy każda społeczność językowa posiada własne preferencje co do sposobu konstruowania dyskursu. Można wiec przyjąć, ze uczący się języka niemieckiego mają problemy z rozpoznaniem i użyciem odpowiednich struktur informacyjnych zarówno w procesie rozumienia jak i przy produkcji zdań strony biernej oraz że wpływ kontekstu może odegrać w tym procesie decydującą rolę

Stellungsmöglichkeiten der Fokuspartikel nur / tylko und ihr Verhältnis zum Bezugsausdruck – im Deutschen und Polnischen

Possibilities of Positioning Focus Particles nur/tylko in German and Polish and their Relation to the Domain Focus particles are distinctively characterized by their capability of changing positions in a sentence. Any change of the position involves a change in the sentence intonation and meaning. In German, focus particles can, as a rule, be attached to any type of the XP phrase, such as DP, PP, AP, VP, or CP. What can be identified as the domain depends on the structural integration of the particle in the sentence. The recognition of the domain is a prerequisite for a correct interpretation of a sentence. The present paper, using the findings of research on the focus particle nur, studies the positioning of the particle ‚tylko‘ in the sentence and its relation to the domain based on the National Corpus of Polish (NKJP).Eine besondere Eigenschaft von FPn ist Variabilität ihrer syntaktischen Positionen im Satz. Den verschiedenen Stellungsmöglichkeiten folgen unterschiedliche Akzentmuster wie auch Bedeutungsunterschiede. Im Deutschen können sich Fokuspartikeln grundsätzlich mit jeder X-bar-Phrase verbinden. Von der Art der strukturellen Einbettung hängt es ab, welcher Teil einer Äußerung als Bezugsausdruck der Fokuspartikel identifiziert wird, was wiederum für die korrekte Interpretation eines Fokuspartikelsatzes entscheidend ist. Der vorliegende Beitrag untersucht kontrastiv zu dem Deutschen die Positionierungsmöglichkeiten der polnischen Fokuspartikel tylko sowie ihr Stellungsverhalten zum Bezugsausdruck. Der Analyse wurden hierbei Sätze des nationalen Korpus der polnischen Sprache (NKJP) unterzogen

Reduction of dynamic error in measurements of transient fluid temperature

Under steady-state conditions when fluid temperature is constant, temperature measurement can be accomplished with high degree of accuracy owing to the absence of damping and time lag. However, when fluid temperature varies rapidly, for example, during start-up, appreciable differences occur between the actual and measured fluid temperature. These differences occur because it takes time for heat to transfer through the heavy thermometer pocket to the thermocouple. In this paper, a method for determinig transient fluid temperature based on the first-order thermometer model is presented. Fluid temperature is determined using a thermometer, which is suddenly immersed into boiling water. Next, the time constant is defined as a function of fluid velocity for four sheated thermocouples with different diameters. To demonstrate the applicability of the presented method to actual data where air velocity varies, the temperature of air is estimated based on measurements carried out by three thermocouples with different outer diameters. Lastly, the time constant is presented as a function of fluid velocity and outer diameter of thermocouple

Положение частиц auch/też, także, również по отношению к их домену в польском и немецком языках

The present paper aims to indicate the relation of focus particles także, też, również (auch) to their domains in the Polish sentence. The study is based on language examples taken from the National Corpus of Polish (NKJP). The investigation poses the question whether the basic patterns which were noticed in relation to the German focus particle auch can also be found as governing the use of również, także, and też. Such regularities, if shown and verified, can inspire further contrastive research in the area of foreign language learning. The findings of the present study shall be viewed as combining the semantic and pragmatic approach to language.The present paper aims to indicate the relation of focus particles także, też, również (auch) to their domains in the Polish sentence. The study is based on language examples taken from the National Corpus of Polish (NKJP). The investigation poses the question whether the basic patterns which were noticed in relation to the German focus particle auch can also be found as governing the use of również, także, and też. Such regularities, if shown and verified, can inspire further contrastive research in the area of foreign language learning. The findings of the present study shall be viewed as combining the semantic and pragmatic approach to language.Le numéro contient uniquement les résumés en anglais.Том не содержит аннотаций на английском языке

L'immunothérapie spécifique dans le traitement de l'asthme d'origine allergique

LILLE2-BU Santé-Recherche (593502101) / SudocSudocFranceF

Dislocation phenomena as topological means of information structure in German and Polish print media

Seit kurzem werden die Versetzungsstrukturen immer haufiger zum Untersuchungsgegenstand der linguistischen Forschung. Dieses Interesse ist kommunikativ-pragmatisch determiniert, d. h. es erfolgt aus dem Bewusstsein ihrer Bedeutung bei der informationsstrukturellen Gliederung von Auserungen. Das Ziel des vorliegenden Beitrags ist die Vorkommenshaufigkeit sowie Vielsichtigkeit der Herausstellungsstrukturen in der betreffenden Funktion in Pressetexten der beiden Sprachen (Deutsch-Polnisch) aufzuzeigen.Dislocation structures are increasingly becoming an object of linguistic research. This interest is determined communicatively and pragmatically, i. e. it results from the awareness of these constructions in information-structural aspects of utterances. The aim of the present paper is to determine frequency of occurrence as well as complexity of dislocation structures in this function in German and Polish print media