temperature

EVALUATING THE STATE OF SANITARY AND HYGIENIC CONDITIONS IN VENTILATED ROOMS

At present, the problem of energy efficiency remains extremely important. Modern building technologies allow you to create houses with the minimum power consumption, using energy efficient external protections, including plastic windows. This leads to a reduction in the heat loss of the room, but there is a danger of reducing the required air exchange.

INFLUENCE OF METAL ALLOYS RADIATIVE CHARACTERISTICS ON METHODICAL ERRORS OF TWO-COLOR COMPENSATIVE AND CLASSICAL THERMOMETRY

Investigations of methodical errors of two-color compensative and classical energy and spectral ratio pyrometry are  performed  under  conditions  of  changeable  radiative  characteristics  of metal  alloys. To  quantitatively  estimate  the  radiative characteristics we  proposed  such  parameters  as  an  average  level  of  emissivity  and  selectivity  factor. As  average  (adjustment) values  of  these  parameters  we  chose  the  values,  which  correspond  to  tungsten  in  vacuum  with  temperature  1600  K  (for wavelengths  0.7  and  0.9 µm).

PRIMARY CONVERTERS FOR TEMPERATURE MEASUREMENT IN METALLURGY

The successful implementation of the systems of automation in metallurgical industry is impossible without the presence of reliable primary information about the parameters of technological process. A temperature is one of basic parameters that determine the quantitative and quality indicators of the final products. Therefore the technological processes of metallurgical industry need the presence of various primary transformers of temperature with high accuracy, sensitivity, stability and resistance to interference.

DEPENDENCE OF THE PYROMETRIC MEASURING TEMPERATURE ON THE EMISSIVITY FACTOR OF OBJECTS

Study  of  the  dependence  of  the  temperature  determination  error  on  the  emissivity  factor  of  materials  is conducted  in  the  paper.  The  mathematical  models,  which  describe  the  ratio  of  thermodynamic  temperature  and  measured imaginary temperatures, taking into account the emissivity factor, are analyzed. The constructions of the full radiation, brightness radiation, and spectral ratio radiation pyrometers are underpinned by the considered models.

DEPENDENCE OF NEURAL NETWORKS TEMPERATURE PREDICTION ERROR ON MEASUREMENT ERROR

The  current  article  describes  the  results  of  the  study  of  the  neural  networks  temperature  prediction  error dependence  on  measurement  errors,  which  are  random,  nonlinear  and  multiplicative  errors.  It  is  noted  applicability  of  the architecture of neural network for temperature prediction. The formula of temperature step response for ideal sensor is given. 

STUDY OF THE TEMPERATURE FIELDS IN THERMOTRANSDUCER’S CASE

The choice of ways of obtaining information about the temperature of the surface layers of a moving object is the crucial in determining  the  type of  temperature transducers. This choice depends on  the  row of specific  factors:  the speed of movement of the measured object relative the object, the state of the surface, the presence of related agents in near-surface layers, the presence of disturbing factors - noise, vibration, etc. The major factor seems to be the value of the heat carried out from the diagnosed object with the help of intermediate substance. 

DEVELOPMENT OF OUTFIT FOR MEASUREMENT OF THE MELT METAL TEMPERATURE IN OPTICAL WAY

Two main methods of contact measurement of steel temperature are applied in industry: with help of disposable  and multiple  used  thermotransducers.  Reusable  ones  are  fixed  to  the  bottom  of  the  graphite  tip  fixed directly on the reinforcement. Then they are able to measure the temperature of the graphite surface. Since it needs to even the graphite temperature and the temperature of the melt metal, the measuring takes some extra time. Therefore the  thermotransducer  is mounted  in  the metal  for a  long  time.

WATER AND AIR FLOWS TEMPERATURE PREDICTION USING NEURAL NETWORK

Current article considers the results of the study of air and water flow temperature prediction error on the number of  inputs  in  neural  network.  Authors  guide  the  architecture  of  neural  network  for  temperature  prediction.  The  formula  of temperature step  response  for  real sensor  is given. Also,  the method  for  calculating  the  time  constants  for  the  temperature step response formula using real measurement data is considered.

METROLOGICAL RELIABILITY OF THERMOELECRIC NANOSENSOR OF QUANTUM TEMPERATURE STANDARD

While studying the physical foundations of the temperature standard, we obtained a quantum unit of temperature as the value of the temperature jump when one electron-phonon scattering per unit time. We expressed it in terms of the ratio of fundamental physical constants h/kB; it is equal to 3.199 493 42 ∙ 10-11 K with a relative standard uncertainty of 59.2 ∙ 10-8. The investigated quantum standard is recommended for use as an "intrinsic standard", which does not require continuously repeated measurements (to check its accuracy) in relation to the current unit of temperature.

PROCESSES OF HEAT AND MASS TRANSFER IN GAS AND HEAT PROTECTIVE SUIT WITH ICE-WATER COLD-STORAGE ACCUMULATORS

The article dwells on the mathematical model of heat and mass transfer processes in „environment-protective clothing-human” system which takes into account simultaneous penetration of ambient heat and toxic chemicals in the multi-layer membrane of garments with air gap. On the basis of this model, the parameters of a gas and heat protective suit are reasonably defined.