НАУКА /3. Депозитарий научных работ:
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По данной предметной области :
Техническая термодинамика-(3)
Теплофизические свойства веществ-(47)
Тепломассобмен-(8)
Механика жидкостей и газов-(1)
Топливо и его подготовка на ТЭС-(2)
Свойства водных растворов, используемых на ТЭС-(1)
Конструкционные материалы-(0)
Информационные технологии-(5)
Теплотехнический эксперимент-(2)
Наноматериалы и нанотехнологии-(1)
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Категория: НАУКА /3. Депозитарий научных работ
Radim Mares and Jana Kalova . Thermophysical Properties Converted from Data and Equations Based on Old Temperature Scales Доклад на 15 Международной конференции по свойствам воды и водяного пара
Thermophysical properties measured before 1990 are based on obsolete temperature scales. In spite of great progress of experimental technique, there are data measured before 1990 that are still considered as very precious. In similar way it is with correlations of old but reliable thermophysical data. The only change of a parameter, as critical temperature, does not guarantee a correct approach to the right conversion. Comparison of values from an equation based on obsolete temperature scale with a new equation calculated for the same numerical values of temperature gives comparison at two different thermal states. There are thermophysical properties the temperature conversion of which depends on derivatives of equation converting an old temperature scale to the new one. Specific heat capacity, coefficient of thermal conductivity etc. could serve as examples of such properties. Complicated situation is with such properties as entropy and properties derived from it. The paper brings discussion of examples of temperature conversion of experimental data and equations as well.
Тема : Теплофизические свойства веществ
Review of Techniques for Thermophysical Property. Kenneth C. MiIls, Lee Courtney, Robert F. Brooks and Brian J. Monaghan The methods available for the measurements of the following thermophysical properties of high temperature melts are reviewed viz. density, viscosity, surface tension, heat capacity, enthalpy, thermal diffusivity and conductivity, electrical conductivity and emissivity. The methods are illustrated with reference to work carried out on molten silicon. In order to combat contamination of the melt from container/sample reactions there has been a gradual switch to the use of (i) containerless methods employing various forms of levitation or microgravity (drop towers, parabolic flights and space experiments) and (ii) sub-second rapid heating and other non-intrusive techniques. However, there are other equally-important conditions which must be addressed to obtain accurate property values, e.g. the control of oxygen partial pressure in surface tension measurements and the selection of the most reliable method to analyse data. It is our contention that equal attention should be given to these problems.
Тема : Теплофизические свойства веществ
S.Ganesh Prakash, R.Ravi, R.P.Chhabra Corresponding states theory and transport coefficients of liquid metals A study of the applicability of CST towards predicting transport coefficients in liquid metals has been undertaken with particular
emphasis on alkali metals. Characteristic parameters were obtained from six different first principles calculations of inter-ionic
potentials of simple metals reported in the literature. A wide variation was observed in the characteristic parameters as reported by
various authors. Among these, the potential parameters of Shyu et al. provided the best correlation of experimental diffusivity and
viscosity data for alkali metals over moderate temperature ranges. However, use of the Goldschmidt diameter as the characteristic
distance parameter and kBTm, where Tm is the melting temperature, as the characteristic energy parameter gave as good, if not better,
results for alkali metals. This parameter set was not found to be satisfactory when non-alkali metals were also included. Chapman’s
characteristic parameters, obtained from a fit to the viscosity data, provided a reasonable correlation of the diffusivity data to most,
but not all metals studied. Fundamental issues associated with attempting to group all liquid metals under a single corresponding
states theory as well with the conventional use of the potential well-depth and the distance at which the potential becomes zero as
characteristic parameters for liquid metals have been pointed out. A preliminary statistical analysis has been performed to assess the
reliability of our predictions in view of the experimental uncertainties in viscosity and diffusivity data.
Тема : Теплофизические свойства веществ
TEMPMEKO 2013
TEMPMEKO 2013
Последний выпуск журнала International Journal of Thermophysics
(Volume 36 Number 8)
Опубликованы отдельные доклады на конференции:
TEMPMEKO 2013 Special Issue 4: Selected Papers of the 12th International Symposium on Temperature, Humidity, Moisture and Thermal Measurements in Industry and Science
.
Обзорный доклад “Toward Reliable Industrial Radiation Thermometry”
Тема : Теплотехнический эксперимент
The realization and the dissemination of thermodynamic temperature scales
Since the establishment of the International Temperature Scale of 1990 (ITS-90), much progress has been made in the development of radiometers and blackbody sources. Cryogenic electrical-substitution radiometry is widely used in detector and radiometer calibrations, and stable, high-temperature metal–carbon eutectic blackbodies are under development. Radiation thermometers can be calibrated for absolute radiance responsivity, and blackbody temperatures determined from the amount of optical power without the use of any fixed points to directly measure thermodynamic temperatures. These thermodynamic temperatures can be measured with lower final uncertainties than the ITS-90 derived temperatures, and these developments will directly impact future international temperature scales.
Тема : Теплотехнический эксперимент
The Viscosity and Self-Diffusion of Rarefied Steam:Refinement of Reference Data. L. R. Fokin and A. N. Kalashnikov Авторы публикации – Фокин Л.Р., Калашников А.Н.
Новые экспериментальные данные по вязкости разреженного водяного пара подтверждают предсказательную способность использования модифицированного (m:6:3) потенциала Штокмайера. Проведена совместная обработка данных по вязкости и коэффициенту самодиффузии пара в диапазоне температур от 280 до 1400 К и рассчитаны уточненные таблицы справочных данных для указанных свойств.
Тема : Теплофизические свойства веществ
Transport Coefficients for the NASA Lewis Chemical Equilibrium Program. Roger A. Svehla. April 1995
This report documents the new transport property data that will be used in the NASA Lewis Research Centers Chemical Equilibrium and Applications Program (CEA). It complements a previous publication that documented the thermodynamic and transport property data then in use. Sources of the data and a brief description of the method by which the data were obtained are given. Coefficients to calculate the viscosity, thermal conductivity, and binary interactions are given for either one, or usually, two temperature intervals, typically 300 to 1000 K and 1000 to 5000 K. The form of the transport equation is the same as used previously. The number of species was reduced from the previous database. Many species for which the data were estimated were eliminated from the database. Some ion-neutral interactions were added.
Available electronically at http://gltrs.grc.nasa.gov/GLTRS
Тема : Теплофизические свойства веществ
W. Wagnera and A. Pruß The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use In 1995, the International Association for the Properties of Water and Steam ~IAPWS!
adopted a new formulation called ‘‘The IAPWS Formulation 1995 for the Thermodynamic
Properties of Ordinary Water Substance for General and Scientific Use’’, which we
abbreviate to IAPWS-95 formulation or IAPWS-95 for short. This IAPWS-95 formulation
replaces the previous formulation adopted in 1984. This work provides information
on the selected experimental data of the thermodynamic properties of water used to
develop the new formulation, but information is also given on newer data. The article
presents all details of the IAPWS-95 formulation, which is in the form of a fundamental
equation explicit in the Helmholtz free energy. The function for the residual part of the
Helmholtz free energy was fitted to selected data for the following properties: ~a! thermal
properties of the single-phase region (prT) and of the vapor–liquid phase boundary
(psr 8r 9T), including the phase-equilibrium condition ~Maxwell criterion!, and ~b! the
caloric properties specific isochoric heat capacity, specific isobaric heat capacity, speed of
sound, differences in the specific enthalpy and in the specific internal energy, Joule–
Thomson coefficient, and isothermal throttling coefficient. By applying modern strategies
for optimizing the functional form of the equation of state and for the simultaneous
nonlinear fitting to the data of all mentioned properties, the resulting IAPWS-95 formulation
covers a validity range for temperatures from the melting line ~lowest temperature
251.2 K at 209.9 MPa! to 1273 K and pressures up to 1000 MPa. In this entire range of
validity, IAPWS-95 represents even the most accurate data to within their experimental
uncertainty. In the most important part of the liquid region, the estimated uncertainty of
IAPWS-95 ranges from 60.001% to 60.02% in density, 60.03% to 60.2% in speed of
sound, and 60.1% in isobaric heat capacity. In the liquid region at ambient pressure,
IAPWS-95 is extremely accurate in density ~uncertainty <60.0001%! and in speed of
sound ~60.005%!.
Тема : Теплофизические свойства веществ
Академик А.И. Леонтьев. Вклад отечественных ученых в теорию теплообмена.
Академик А.И. Леонтьев. Вклад отечественных ученых в теорию теплообмена – исторический обзор,
опубликованный в 1999 г. в журнале «Теплофизика и аэромеханика»
«В одной статье невозможно оценить вклад в теорию теплообмена всех отечественных ученых, поэтому я, как правило, рассматривал только те работы, которые получили признание мировой научной общественности…»
Текст обзора
Тема : Тепломассобмен
БЕЛОКОНОВА Н.А. Автореферат докторской диссертации:СОВЕРШЕНСТВОВАНИЕ МЕТОДОЛОГИИ КОНТРОЛЯ И УПРАВЛЕНИЯ ТЕХНОЛОГИЧЕСКИМИ ПРОЦЕССАМИ ПОДГОТОВКИ ВОДЫ НА ТЕПЛОВЫХ ЭЛЕКТРОСТАНЦИЯХ. Екатеринбург, 2009 Работа выполнена в ГОУ ВПО "Уральский государственный технический университет – УПИ имени первого Президента России Б.Н. Ельцина" и в химической службе Свердловского филиала ОАО «ТГК-9»
Цель работы: совершенствование методологии аналитического и технологического контроля вод ТЭС путем поиска, исследований, разработки, обоснования и реализации новых методик определения количественного содержания органических примесей и критериев оценки их физико-химических свойств для снижения накипеобразования и коррозии поверхностей нагрева теплоэнергетического оборудования.
Тема : Свойства водных растворов, используемых на ТЭС
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