H112F Radiation Errors in Temperature Measurement

H112F Radiation Errors in Temperature Measurement

A small scale bench top accessory designed to experimentally investigate how measured temperatures can be influenced by the effects of radiation, temperature sensor design and surface finish. Three temperature sensors of different form and surface finish are mounted centrally in a circular stainless steel duct that is surrounded locally by an electrical heater.

An additional temperature sensor records the temperature of the inside of the heated duct adjacent to the centrally mounted thermocouples. A radiation shield may be raised or lowered over the centrally mounted thermocouples to investigate the effects of shielding.

H112F Radiation Errors in Temperature Measurement

A small scale bench top accessory designed to experimentally investigate how measured temperatures can be influenced by the effects of radiation, temperature sensor design and surface finish.

Three temperature sensors of different form and surface finish are mounted centrally in a circular stainless steel duct that is surrounded locally by an electrical heater .An additional temperature sensor records the temperature of the inside of the heated duct adjacent to the centrally mounted thermocouples.

A radiation shield may be raised or lowered over the centrally mounted thermocouples to investigate the effects of shielding

The circular duct is mounted on the discharge from a centrifugal fan. Air from the fan is blown through the duct past the temperature sensors at a controlled velocity of between 0 and 8m/s. The air velocity is measured by an in duct anemometer.

The duct heater is controlled using the variable 240v ac supply from the H112 Heat Transfer Service Unit. The heater power supply and temperature sensors connect to the H112 Heat Transfer Service Unit while velocity is recorded on auxiliary instrumentation supplied as part of the H112F unit. All relevant components are secured to a bench mounted plate that is designed to be situated alongside the H112 Heat Transfer Service Unit

Requires the H112 Heat Transfer Service Unit for operation.

  • Demonstration of how temperature measurements can be affected by radiant heat transfer to a sensor from its surroundings and to show:
  • Effect of temperature difference between the sensor and its surroundings
  • Effect of air velocity.
  • Effect of sensor size.
  • Effect of sensor Emissivity.
  • Demonstration of methods of reducing the errors in temperature measurement, which are due to radiation from a source that is visible to the sensor. Including:
  • Use of a radiation shield between the sensor and the source of radiation.
  • Design of a radiation resistant sensor.