Temperature & Heat Flux Sensor MCT
High Frequency Micro Thermocouple, adaptable to any Surface for Measuring Surface Temperatures and Heat Flux into the Surface
Typical Applications
These special thermocouples are ideal for very fast measurements of temperature changes on the surface of a body. These sensors are ideal for measurements during a short individual event. In the latter case, these measurements can be used to calculate heat flows into the surface. From the signal of the surface temperature change, the convective heat flow into the wall can be determined. The thermocouple is regarded as a half-infinite- body. The max. measuring time ends when the rear part of the sensor also starts to warm up after approx. 40 to 100 ms since then the calculation basis are lost.
To calculate the heat flow we offer the program Heat Flux Calculator HFC. It calculates the heat flow in a simple manner using the temperature and material data of the sensor.
The sensor is small enough to accommodate in each contour e.g. in a wing nose of a space shuttle. In addition, its sensitive end can be completely inserted into the surface by filing and grinding. Alternatively, the end of the probe can be coated with a finished metal coating. This offers the advantage of a longer service life at higher temperatures, but has the disadvantage of a fixed geometry.
Heat flux sensor MCT 19, 36 and MCTB 48 with bore hole for central pressure measurement. Alternative design with thread and /or short cable for easy screwing
The MCTB 48 model also offers the unique possibility by coaxially installing a pressure probe to measure changes of pressure at one and the same position as the temperature as well. Our pressure probe M60-1LM3 can be screwed into the thermocouple with its thread.
If the experiments take place at constantly high temperatures, the surface begins to corrode after some time and the signal disappears. The duration of the measurement for type E is about 35 minutes at temperatures of 615 °C and about 8 minutes at 715 °C. In these cases, the thermocouple can be refurbished by re-grinding the sensor surface. This leads to a almost unlimited durability.
To amplify the low signals of the thermocouple we recommend a voltage amplifier with 1 MHz bandwidth, like our MVA 10 with 1 MHz filter.
As far as what has been said so far is concerned, the sensors are confronted with both convective and thermal radiation. In the measurements, the sum of both heat components is measured.
If you only want to determine the heat flow of the thermal radiation, we offer a special design. In this, the blackened thermocouple is placed behind a window made of ZnS glass. We also supply the installation adapters for direct installation.
Technical Data
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Type of thermocouple: |
Type E (Type K as a special design) |
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Material: |
Chromel - Constantan, coaxial |
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Temperature range: |
Type E: - 200 to 900 °C |
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Type K: - 200 to 1170°C |
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Temperature sensitivity: |
0.5 K |
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Heat flux: |
20 KW/m² to 20 MW/m² |
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Response time: |
3 μs |
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√ ρ c k: |
About 9000 W √s/m²K |
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Diameter: |
1.9, 3.6 and 4.8 mm |
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Size: |
MCT 19: d = 1.9 x 26 mm |
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MCT 36: d = 3.6 mm x 17 mm |
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MCTB 48: d = 4.8 x 25 mm |
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Special version with bore hole for pressure measurement, diameter for adjustment between 1-3 mm |
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Sensitivity: |
About 60 µV/K for type E, 39.9 µV/K for type K , (s. IEC-584 T1) |
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Calibration: |
Calibrated by the University of Aachen |
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Tip: |
Can be individually shaped by the user |
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Specials: |
For the thermocouple MCTB 48 a coaxial borehole with d = 0.8 mm for connecting a pressure probe with a diameter of 1.9 to 3 mm is possible (e.g. M60-1L-M3) |
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Connection: |
Via 2 m temperature resistance coaxial cable with BNC pos. |
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Amplification: |
Amplifier is needed. We recommend our MVA 10 plus 1 MHz filter |
Article-No. 100-001-0: HFC Heat Flux Calculator program
Article-No. 100-001-1: MCT 19, type E, diameter 1.9 mm
Article-No. 100-001-2: MCT 36, type E, diameter 3.6 mm
Article-No. 100-001-21: Special version incl. dapter for MCT 19 for measuring convestive and radiant heat flux
Article-No. 100-001-22: Special version with ZnS window adapter for MCT 19 for measuring radiant heat flux only
Article-No. 100-001-3: MCTB 48, diameter 4.8 mm
Article-No. 100-001-7: Surcharge for a short 20 cm cable plus connection to a 2 m extension cable with BNC pos. for sensor with screw for easy screwing
Article 100-001-8: Surcharge for thread for easier mount, M2, M3.5 and M5 with counter nut
Article 100-001-9: Surcharge for type K instead of type E
Publications
Olivier H.:
Thin Film Gauges and Coaxial Thermocouples for Measuring Transient Temperatures
Olivier H., Grönig H.:
Instrumentation Technique of Aachen Shock Wave Tunnel - ICIASF 1995a3
Hans-Jürgen Fahl:
The Validation of the Explosive Fumes Dynamics in Rooms
Sensitivity of the Coaxial Thermocouple MCT:
corresponding to IEC 584 T1 for Type E
Download
- Brochure Coaxial Thermocouple MCT [PDF, 427 KB]
- Brochure Heat Flux Calculator – HFC [PDF, 752 KB]