Temperature measurement average

The temperature for methane and butane calculated with the isothermal model is a factor 1.4 times greater than the average temperature measured by Lihou and Maund (1982) in their small-scale tests, although higher local maximum temperatures were measured. In this model, combustion is stoichiometric, thus leading to very high fireball temperatures which, in turn, lead to high radiation emissions. Effective surface emissions measured experimentally were one-half the value calculated from this model, because combustion is not stoichiometric and emissivity is less than unity. 

The temperature distribution within the different shelves compared with the average temperature measured within the stable phase of the process and the average shelf temperature must comply with supplier specifications. 

In the following section, we give a few values of the average temperature measured by viscosimetry or by light scattering however, these values cannot validly be compared with simple theoretical results. 

Convection involves the transfer of heat between a surface at a given temperature (Tj) and fluid at a bulk temperature (T ). The exact definition of the bulk temperature (Tj,) varies depending on the details of the situation. For flow adjacent to a hot or cold surface, is the temperature of the fluid far from the surface. For boiling or condensation, Tb is the saturation tanperature of the fluid. For flow in a pipe, is the average temperature measured at a particular cross section of the pipe. 

Temperature is an often underestimated measuring parameter. An accurate average temperature measurement is essential to achieve accurate inventory calculations. Spot measurements are not useful when the product temperature is stratified. 

In general, average temperature-measuring elements are used in case of temperature stratification. The latest development is the multitemperature thermometer (MTT) shown in Fig. T-26 that utilizes 16 thermosensors evenly distributed over the maximum possible liquid height. A very accurate class A PtlOO element at the bottom is the reference. Accuracies of better than 0.05°C (0.08°F) are possible. The elements can also be individually measured to obtain temperature profiles and vapor temperatures. MTTs are available with both nylon and stainless steel protection tubes. It provides a rugged construction suitable for the harsh environments of a bulk storage tank. 

Another type of average temperature measuring element is the multiresistance thermometer (MRT). Its operation is based on a number of copper wire temperature sensing elements of different lengths. Average temperature measurement is achieved by measuring the longest fully immersed resistance thermometer chosen... 

The measurement techniques most frequently used are derived from Raoult s and Van t Hoff s laws applied to cryometry, ebulliometry, osmometry, etc. They are not very accurate with errors on the order of ten per cent. Consequently, the molecular weight is often replaced by correlated properties. The mean average temperature or viscosity can thus replace molecular weight in methods derived from ndM. 

Temperature. Temperature sensor selection and installation should be based on the process-related requirements of a particular situation, ie, temperature level and range, process environment, accuracy, and repeatabiHty. Accuracy and repeatabiHty are affected by the inherent characteristics of the device and its location and installation. For example, if the average temperature of a flowing fluid is to be measured, mounting the device nearly flush with... 

The resistance method gives an average temperature of the whole winding. Some parts will be hotter than others usually the end turns will be somewhat cooler than parts of the winding in the middle of the iron core. NEMA committee members have been collecting test data on many machines to determine the correlation between temperature measurements by detector and by resistance, and the standards are periodically updated to reflect any of the technology improvements. 

At low temperatures the average temperatures ealeulated from the individual measurements eorresponded to the temperature setting. They were appreeiably lower at higher temperatures and it was found that the temperature setting eorresponded to the highest temperature that eould be reaehed in the individual measurements. It was also evident that the edge of the hotplate was eolder than the middle, i.e. the effeetive measured temperature was not the same everywhere over the surface of the hotplate a homogeneous temperature distribution is most likely to be found in the center of the plate. 

Surface condition Machined, abraded and pickled surfaces all exhibit much the same behaviour in water, and after exposure of up to about one year at temperatures less than I00°C average attack measures 0 0025-0 0050mm/y. Almost always, however, corrosion of beryllium in water is accompanied by pitting and, on machined surfaces, pits of as much as 0-25mm have been observed in 0-0005M hydrogen peroxide at 85°C. Under similar conditions, annealed material has been found to be somewhat less resistant to attack than either machined or pickled surfaces. 

Equation (4.3) is exactly true only if q is an infinitesimal amount of heat, causing an infinitesimal temperature rise, dr. However, unless the heat capacity is increasing rapidly and nonlinearly with temperature, equation (4.3) gives an accurate value for Cp at the average temperature of the measurement Continued addition of heat gives the heat capacity as a function of temperature. The results of such measurements for glucose are shown in Figure 4.1.2... 

Consider now a situation in which the bias limits in the temperature measurements are uncorrelated and are estimated as 0.5 °C, and the bias limit on the specific heat value is 0.5%. The estimated bias error of the mass flow meter system is specified as 0.25% of reading from 10 to 90% of full scale. According to the manufacturer, this is a fixed error estimate (it cannot be reduced by taking the average of multiple readings and is, thus, a true bias error), and B is taken as 0.0025 times the value of m. For AT = 20 °C, Eq. (2.9) gives ... 

DC current was supplied through the development and test sections for direct heating. The outer temperature on the heated wall was measured by means of an infrared radiometer. Experiments were carried out in the range of Re = 10-450. The average Nusselt number was calculated using the average temperature of the inner tube wall and mean temperature of the fluid at the inlet and outlet of the tube. 

There s another reason why the computed solution average temperature had decreasing accuracies in Tests 1, 2 and 3 respectively. The reason is that we started with increasingly viscous solutions, which caused the response time of the temperature measurement to increase rapidly. This response time becomes even more significant because as the solution viscosity increases there are significant rises in the reaction rates and temperatures. 

Since we did not measure the conversion during the experiment, we computed the equilibrium vapor pressure at the average solution temperature. We believe that, for safety design, the equilibrium vapor pressure is an adequate estimate of the styrene vapor pressure. For example, even at a 50% conversion, the difference is only 10 at the experimental temperatures. Figures 6, 7 and 8 compared the observed pressures with the computed total pressures. The latter were based on the equilibrium vapor pressure. As expected, there were increasing variations in Tests 1, 2 and 3 respectively because of their higher initial conversions. From these figures we can verify that our pressure and temperature measurements were in phase with respect to time. 

The power of this technique is due to the fact that the temperature-depth profile is a direct remnant of paleotemperatures at the ice-sheet surface. It provides a quantitatively accurate measure of long-term average temperatures. This allows the stable isotope records to be calibrated for major climate events (Cuffey et ah, 1995). 

A similar experiment was conducted using N-299 carbon black. In this case the premastication was limited to 3 min of mixing time. The average batch temperature measured after this mixing operation was 309°F. Each experiment was performed in duplicate the average of two mixes is shown in Figure 16.6. The viscosity of the final control compound was similar to that of the premasticated mbber. 

The q(T) can be independently measured by a viscometer and the value of y is determined by the PCS measurement at a certain temperature (typically 21 22 °C). Under the condition that the hydrodynamic diameter of the probe molecule is constant in the temperature range examined, we can obtain the temperature of the confocal area. It is worth noting that the present method estimates average temperature inside the confocal volume of the microscopic system because ECS provides the average value of the translational diffusion velocity over multiple fluorescent molecules passing through the sampling area. 

In addition to the four detectors used to detect backscattered radiation from the sample, there is a fifth detector to measure the transmission spectrum of the reference absorber (a- Fe, a- Fe203, Fc304 see Fig. 3.16). Sample and reference spectra are recorded simultaneously, and the known temperature dependence of the Mossbauer parameters of the reference absorber can be used to give a measurement of the average temperature inside the SH, providing a redundancy to measurements made with the internal temperature sensor (see Sect. 3.3.4). 

This is equivalent to assuming a constant standard error in the measurement of the j response variable, and at the same time the standard errors of different response variables are proportional to the average value of the variables. This is a "safe" assumption when no other information is available, and least squares estimation pays equal attention to the errors from different response variables (e.g., concentration, versus pressure or temperature measurements). 

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