C-2500 HTSC-2500 HTS高温传导系统

The Model C-2500-HTS Thermal Conductivity system is designed for measureing the thermal

conductivities of highly conducting materials from room temperatures to 1000

 

SPECIFICATIONS

Conductivity Range:

0.02 to 50 BTU/hr.ft. F

Temperature Range:

R.T. to 1000 C

Accuracy:

+/- 5%

Sensing Surfaces:

Nickle alloys/air cooling. Interface thermal

resistance correction curve supplied

Calibration:

ASTM C177-76

Heat Guard:

Automatic

Readout In Following Units:

Sample Heat Flux....BTU/hr.ft. (Dual Readouts)

Sample Ambient Temperature.......................... F

Sample Temperature Difference....................... F

 

THE HIGH TEMPERATURE, THERMAL

CONDUCTIVITY MEASUREMENT

TECHNIQUE

The contact(sensing) surfaces of the high temperature conductivity system are composed of traceable Alumel, whose thermoelectric and physical properties are known.

 

A disc of Chromel, whose properties are also known as a function of temperature, is placed in thermal, and electrical contact between the Alumel surfaces. At a constant heat flow, a temperature difference will be established across the Chromel disc, consequently, a thermoelectric voltage will be generated between the Alumel surfaces. This voltage is directly related to the heat flux through the Alumel surface Two such heat flux sensors encompass the sample to be measured, thus, the heat flux entering the sample can be averaged with the heat flux exiting the sample. The values so obtained obviate the necessity for guarded hot plates,

thus yielding greater accuracy

 

The temperature difference across the sample is sensed with two Type “K” Chromel/Alumel thermocouple discs which provide an average value over the entire sample surface.