Der Schwerpunkt in der Erprobungsph

Der Schwerpunkt in der Erprobungsphase lag auf der Optimierung der Randbedingungen innerhalb der Messapparatur. Dabei stellte sich die Aufgabe, geeignete Maßnahmen zur Erzeugung eines stationären Temperaturfeldes in den drei unterschiedlichen Betriebsweisen zu treffen, was für eine korrekte Auswertung der effektiven Wärmeleitfähigkeit unerlässlich ist. Sowohl in den Versuchen unter Normaldruck als auch in den Versuchen im Unterdruckbereich konnten die Randbedingungen durch regelungstechnische Maßnahmen optimiert werden. Durch eine gezielte Einstellung einer Temperaturdifferenz über den Probenkörper sowie der Temperaturen der Heizzonen kann das Temperaturfeld beeinflusst werden. Um den Anteil der Fehlwärmeströme an der mittleren Heizplatte und der elektrischen Verlustleistungen an der gesamten Heizleistung zu minimieren, wurde mit steigender Temperatur auch eine größere Temperaturdifferenz über dem Probenkörper eingestellt (bis zu 50 K bei 950 °C). Außerdem wurde ein möglichst gleichmäßiges Temperaturfeld im Druckbehälter angestrebt. Aus diesem Grund musste die über den Probenkörper eingestellte Temperaturdifferenz auch in etwa in den Schutzheizzonen eingestellt werden. Die gewählte Temperaturdifferenz zwischen der Plattenanordnung und dem äußeren Schutzheizring ermöglicht eine Beeinflussung des radialen Temperaturgradienten innerhalb der Plattenanordnung. Im Unterdruckbereich wurde außerdem die Leistung der mittleren Heizplatte manuell geregelt. Hierdurch konnte die Schwankung der Heizleistung der mittleren Heizplatte und infolgedessen der effektiven Wärmeleitfähigkeit, welche besonders im Bereich sehr niedriger Drücke und Temperaturen relativ hoch ist, minimiert werden.

結果 (英文) 1:

In the test phase focused on the optimization of the conditions within the measuring equipment. It turned the task, to take appropriate measures to create a stationary temperature field in the three different operating modes, what is essential for a correct evaluation of the effective thermal conductivity. In trials under normal pressure, as well as in the experiments in the low pressure area the boundary conditions could be optimized through control measures. The temperature field can be influenced by a specific setting of a temperature difference across the specimens, as well as the temperature of the heating zones. To minimize the proportion of incorrect heat flows to the Middle plate and the electrical losses on the entire heating performance, a greater temperature difference over the specimens ceased with increasing temperature (up to 50 K at 950 ° C). Also aimed at a possible uniform temperature field in the pressure tank. For this reason, the temperature difference set via the test specimens had to be also about set in protection heating zones. The selected temperature difference between the plate arrangement and the outer heat shield allows an influence of radial temperature gradient within the plate arrangement. In the low pressure area, the performance of the Middle plate was regulated also manually. This could the fluctuation of the heat output of the Middle plate and as a result, the effective thermal conductivity, which very low pressures and temperatures are relatively high, especially in the area be minimized.

結果 (英文) 2:

The focus in the testing phase was on optimizing the boundary conditions within the measuring apparatus. Here the task is to take appropriate measures for generating a steady temperature field in the three different modes of operation, which is essential for a correct evaluation of the effective thermal conductivity presented. Both in the experiments at atmospheric pressure as well as in the experiments in the vacuum range, the boundary conditions could be optimized by technical control measures. By selective adjustment of a temperature difference across the specimen as well as the temperatures of the heating zones the temperature field can be influenced. In order to minimize the percentage of false heat flows on the central heating plate and the electrical power losses of the total heating power, a greater temperature difference was set above the test specimen (up to 50 K at 950 ° C) with increasing temperature. In addition, the most uniform temperature field has been sought in the pressure vessel. For this reason, the set on the specimen temperature difference had to be set in about the Schutzheizzonen. The chosen temperature difference between the panel assembly and the outer Schutzheizring enables influencing the radial temperature gradient within the disk array. In low pressure area also the performance of the central hot plate was controlled manually. This enabled the variation of the heating power of the central heating plate and, consequently, the effective heat conductivity in the range of very low pressures and temperatures is particularly relatively high, can be minimized.

結果 (英文) 3:

the focus of the work was to optimize the boundary conditions within the measuring apparatus. it was the task of appropriate measures to produce a stationary temperaturfeldes in the three different modes of operation to take for a correct evaluation of the effective thermal conductivity is essential. in both the experiments under normal pressure as well as in the experiments in unterdruckbereich were the boundary conditions by regulatory measures are optimized. through targeted recruitment of a temperature difference on the probenkörper and the temperatures of the heating zones can temperaturfeld are influenced. the proportion of fehlwärmeströme the middle hot plate and electric verlustleistungen in the total heat output to minimize, with increasing temperature, a greater temperature difference on the probenkörper set (up to 50 k at 950 degrees c). in addition, as a regular in the pressure temperaturfeld was sought. for this reason, had to on the probenkörper set temperature difference also in the schutzheizzonen are employed. the selected temperature difference between the plattenanordnung and outer schutzheizring allows radial temperature gradients within the influence of the plattenanordnung. in unterdruckbereich was also the performance of the middle hot plate manually controlled. thereby the variation of the capacity of the middle hot plate and, consequently, the effective thermal conductivity, which, particularly in the area of very low pressures and temperatures is relatively high, is minimized.