Gesamtliste der Publikationen

Anzahl der Treffer: 997
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Fröhlich, Thomas; Hohmann, Michael; Schalles, Marc
Calibration bench for heat flux sensors. - In: Journal of thermoelectricity, ISSN 1607-8829, (2015), 1, S. 49-59

Gatzemeier, Benno; Fröhlich, Thomas; Fehling, Thomas; Heydenbluth, Detlef
Sartorius susceptometer for precise measurement of susceptibility and magnetization of weights. - In: 5th International Metrology Conference 2014 (CAFMET 2014), ISBN 978-1-63439-598-4, (2015), S. 109-112

Hohmann, Michael; Marin, Sebastian; Schalles, Marc; Krapf, Gunter; Fröhlich, Thomas
Dry block calibrator using heat flux sensors and an adiabatic shield. - In: International journal of thermophysics, ISSN 1572-9567, Bd. 36 (2015), 8, S. 2085-2098

The main problems of conventional dry block calibrators are axial temperature gradients and calibration results which are strongly influenced by the geometry and the thermal properties of the thermometers under test.To overcome these disadvantages, a new dry block calibrator with improved homogeneity of the inner temperature fieldwas developed for temperatures in the range from room temperature up to 600 ˚C. The inner part of the dry block calibrator is a cylindrical normalization block which is divided into three parts in the axial direction. Between these parts, heat flux sensors are placed to measure the heat flux in the axial direction inside the normalization block. Each part is attached to a separate tube-shaped heating zone of which the heating power can be controlled in a way that the axial heat flux measured by means of the heat flux sensors is zero. Additionally, an internal reference thermometer is used to control the absolute value of the temperature inside the normalization block. To minimize the radial heat flux, an adiabatic shield is constructed which is composed of a secondary heating zone that encloses the whole assembly. For rapid changes of the set point from high to low temperatures, the design contains an additional ventilation system to cool the normalization block. The present paper shows the operating principle as well as the results of the design process, in which numerical simulations based on the finite element method were used to evaluate and optimize the design of the dry block calibrator. The final optimized design can be used to build a prototype of the dry block calibrator.



http://dx.doi.org/10.1007/s10765-015-1943-y
Oliveira, Rafael S.; Fröhlich, Thomas; Lepikson, Herman A.; Winter, Simon; Theska, René
Uncertainty of measurement for the inertial torque estimation in angular acceleration ramps of rotating shafts. - In: Proceedings of the 15th international conference of the European Society for Precision Engineering and Nanotechnology, (2015), S. 165-166

Ullmann, Vinzenz; Emam, Sherief; Manske, Eberhard;
White-light interferometers with polarizing optics for length measurements with an applicable zero-point detection. - In: Measurement science and technology, ISSN 1361-6501, Bd. 26 (2015), 8, S. 084010, insges. 15 S.

https://doi.org/10.1088/0957-0233/26/8/084010
Manske, Eberhard; Füßl, Roland; Mastylo, Rostyslav; Vorbringer-Dorozhovets, Nataliya; Birli, Oliver; Jäger, Gerd
Ongoing trends in precision metrology, particularly in nanopositioning and nanomeasuring technology. - In: Technisches Messen, ISSN 2196-7113, Bd. 82 (2015), 7/8, S. 359-366

http://dx.doi.org/10.1515/teme-2015-0011
Ullmann, Vinzenz; Kühnel, Michael; Kühnel, Michael *1981-*; Manske, Eberhard;
Concentric run-out error determination of rotary tables with an interferometric probe head :
Interferometrische Rundlauffehlerbestimmung von Drehtischen für die optische Rundheitsmessung. - In: Technisches Messen, ISSN 2196-7113, Bd. 82 (2015), 6, S. 299-308

http://dx.doi.org/10.1515/teme-2015-0021
Vasilyan, Suren; Fröhlich, Thomas
Direct force compensation on Lorentz force flowmeters for electrolyte flow measurements. - In: 2015 IEEE/OES eleventh current, waves and turbulence measurement (CWTM), ISBN 978-1-4799-8419-0, (2015), insges. 7 S.

http://dx.doi.org/10.1109/CWTM.2015.7098115
Schalles, Marc; Fröhlich, Thomas; Flügge, Jens
PCM-shielding of precision measuring equipment by means of latent heat. - In: Precision engineering, Bd. 42 (2015), S. 80-84

https://doi.org/10.1016/j.precisioneng.2015.04.002
Fröhlich, Thomas; Augustin, Silke; Ament, Christoph
Temperature-dependent dynamic behavior of process temperature sensors. - In: International journal of thermophysics, ISSN 1572-9567, Bd. 36 (2015), 8, S. 2115-2123

For a number of applications in control and safety value monitoring, a profound knowledge of the dynamic behavior of process temperature sensors is of great importance. Sensor test procedures and model identification methods are state of the art for small temperature changes, i.e., steps. For wider temperature ranges, the temperature dependency of the material characteristics is significant, too. The resulting non-linearities limit the utilization of classical model concepts. In this paper, we introduce and solve a non-linear ordinary differential equation for the linear dependency of the material characteristic parameters, i.e., for the basic case of non-constant material parameters. The analytic solution will be explained, and the results are discussed and compared to a finite element method model of a basic cylinder.



http://dx.doi.org/10.1007/s10765-015-1869-4