Equipment needed for H1 lab.
Task (as outlined in main handout on Environmental Measurement)
A battery-powered data logger is available with up to 8 thermistor sensors on long leads and a humidity sensor. Set up the equipment to record the distribution of air (not surface) temperature across two orthogonal cross-sections of the room at a chosen time, preferably when the heating has been in operation for a few hours. In each case, note the main heat sources and sinks, ventilation conditions, no. of occupants, etc. Then set up to do a set of readings over 48 hours.
For the 48 hour reading you may wish to use a larger number of sensors by also setting up the 6 thermistor sensors on long leads, and a humidity sensor provided. These can be placed along and across the room and preferably also outside. Set the logger to take readings at say five-minute intervals over a 48-hour period.
Use these graphs to present and analyse the temperature and humidity history of the room. Present your readings in an appropriate form (preferably graphical); and suggest the causes and significance of any deviations from uniform temperature. Comment on the performance of the instruments.
Accompany the transverse profile thermistor measurements with an investigation of the response of the occupants – and also record humidity and 'globe' temperature. Note the occupants' activity, clothing, air movement, etc. – and compare with published standards. An infrared thermometer is available to measure surface temperature – its calibration may need checking.
- Coursework handout
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Equipment : 1206 logger with 8 thermistors (most leads up to 10 m, some up to 20 m) and a humidity probe. 1256 Squirrel logger with 4 thermistors (leads up to 20 m), 2 thermistors with shorter leads and a humidity probe.
Infrared thermometer (CHY-121, Rapid 85 or Raytek ST), Hand-held temperature and humidity meter, Globe device.