Time-Resolved Micro-Raman Thermometry for Microsystems in Motion

2008 ◽  
Vol 130 (12) ◽  
Author(s):  
Justin R. Serrano ◽  
Sean P. Kearney

Micro-Raman thermometry has been demonstrated to be a feasible technique for obtaining surface temperatures with micron-scale spatial resolution for microelectronic and microelectromechanical systems (MEMSs). However, the intensity of the Raman signal emerging from the probed device is very low and imposes a requirement of prolonged data collection times in order to obtain reliable temperature information. This characteristic currently limits Raman thermometry to steady-state conditions and thereby prevents temperature measurements of transient and fast time-scale events. In this paper, we discuss the extension of the micro-Raman thermometry diagnostic technique to obtain transient temperature measurements on microelectromechanical devices with 100 μs temporal resolution. Through the use of a phase-locked technique we are able to obtain temperature measurements on electrically powered MEMS actuators powered with a periodic signal. Furthermore, we demonstrate a way of obtaining reliable temperature measurements on micron-scale devices that undergo mechanical movement during the device operation.

Author(s):  
Justin R. Serrano ◽  
Sean P. Kearney

Micro-Raman thermometry has demonstrated to be a feasible technique for obtaining micron-scale spatial resolution of microelectronic and micro-electromechanical system (MEMS) temperatures. However, the low intensities of the Raman signals emerging from the device under study force the need for prolonged data collection times in order to obtain reliable temperature information. This characteristic currently limits Raman thermometry to steady state conditions, and thereby prevents temperature measurements of transient and fast time-scale events. In this paper we discuss the extension of the micro-Raman thermometry diagnostic technique to obtain transient temperature measurements on microelectromechanical devices with 100 μs temporal resolution. Through the use of a phase-locked technique we are able to obtain temperature measurements on electrically-powered MEMS actuators powered with a periodic signal. Furthermore, we demonstrate a way of obtaining reliable micro-scale temperature measurements on devices that undergo mechanical movement during the device operation.


2016 ◽  
Author(s):  
M. Willsch ◽  
T. Bosselmann ◽  
D. Gaenshirt ◽  
J. Kaiser ◽  
M. Villnow ◽  
...  

2020 ◽  
Author(s):  
L. I. Shekhtman ◽  
A. S. Arakcheev ◽  
V. M. Aulchenko ◽  
V. N. Kudryavtsev ◽  
V. D. Kutovenko ◽  
...  
Keyword(s):  

Author(s):  
Patrick Nau ◽  
Zhiyao Yin ◽  
Oliver Lammel ◽  
Wolfgang Meier

Phosphor thermometry has been developed for wall temperature measurements in gas turbines and gas turbine model combustors. An array of phosphors has been examined in detail for spatially and temporally resolved surface temperature measurements. Two examples are provided, one at high pressure (8 bar) and high temperature and one at atmospheric pressure with high time resolution. To study the feasibility of this technique for full-scale gas turbine applications, a high momentum confined jet combustor at 8 bar was used. Successful measurements up to 1700 K on a ceramic surface are shown with good accuracy. In the same combustor, temperatures on the combustor quartz walls were measured, which can be used as boundary conditions for numerical simulations. An atmospheric swirl-stabilized flame was used to study transient temperature changes on the bluff body. For this purpose, a high-speed setup (1 kHz) was used to measure the wall temperatures at an operating condition where the flame switches between being attached (M-flame) and being lifted (V-flame) (bistable). The influence of a precessing vortex core (PVC) present during M-flame periods is identified on the bluff body tip, but not at positions further inside the nozzle.


Author(s):  
R. D. Burke ◽  
P. Olmeda ◽  
J. R. Serrano

A novel experimental procedure is presented which allows simultaneous identification of heat and work transfer parameters for turbocharger compressor models. The method introduces a thermally transient condition and uses temperature measurements to extract the adiabatic efficiency and internal convective heat transfer coefficient simultaneously, thus capturing the aerodynamic and thermal performance. The procedure has been implemented both in simulation and experimentally on a typical turbocharger gas stand facility. Under ideal conditions, the new identification predicted adiabatic efficiency to within 1% point1 and heat transfer coefficient to within 1%. A sensitivity study subsequently showed that the method is particularly sensitive to the assumptions of heat transfer distribution pre- and postcompression. If 20% of the internal area of the compressor housing is exposed to the low pressure intake gas, and this is not correctly assumed in the identification process, errors of 7–15% points were observed for compressor efficiency. This distribution in heat transfer also affected the accuracy of heat transfer coefficient which increased to 20%. Thermocouple sensors affect the transient temperature measurements and in order to maintain efficiency errors below 1%, probes with diameter of less than 1.5 mm should be used. Experimentally, the method was shown to reduce the adiabatic efficiency error at 90 krpm and 110 krpm compared to industry-standard approach from 6% to 3%. However at low speeds, where temperature differences during the identification are small, the method showed much larger errors.


2019 ◽  
Vol 3 (2) ◽  
pp. 6
Author(s):  
Hartmut Borchert ◽  
Stefan Brieschenk ◽  
Berthold Sauerwein

Author(s):  
Richard Burke ◽  
Pablo Olmeda ◽  
José Ramón Serrano

A novel experimental procedure is presented which allows simultaneous identification of heat and work transfer parameters for turbocharger compressor models. The method introduces a thermally transient condition and uses temperature measurements to extract the adiabatic efficiency and internal convective heat transfer coefficient simultaneously, thus capturing the aerodynamic and thermal performance. The procedure has been implemented both in simulation and experimentally on a typical turbocharger gas stand facility. Under ideal conditions, the new identification predicted adiabatic efficiency to within 1%point and heat transfer coefficient to within 1%. A sensitivity study subsequently showed that the method is particularly sensitive to the assumptions of heat transfer distribution pre and post compression. If 20% of the internal area of the compressor housing is exposed to the low pressure intake gas, and this is not correctly assumed in the identification process, errors of 7–15%points were observed for compressor efficiency. This distribution in heat transfer also affected the accuracy of heat transfer coefficient which increased to 20%. Thermocouple sensors affect the transient temperature measurements and in order to maintain efficiency errors below 1%, probes with diameter of less than 1.5mm should be used. Experimentally, the method was shown to reduce the adiabatic efficiency error at 90krpm and 110krpm compared to industry standard approach from 6% to 3%. However at low speeds, where temperature differences during the identification are small, the method showed much larger errors.


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