Temperature Correction Factor

If the shift caused by temperature is known then the response at a reference temperature can be used to predict the response at other temperatures. In this work, the temperature of 20 °C is taken as the reference temperature. To. The temperature factor. Ft, which can be applied to the response at the reference temperature to estimate the response at other temperatures, can be obtained by dividing the data collected at temperature T, by the corresponding data collected at temperature To. It can be expressed as  

Temperature factor for temperature T e, Strain at temperature T and time i Eof- Strain at reference temperature To and time i n Number of readings 

Because of the similarity in the shape of the response curves, the temperature factor is almost constant for a given temperature. 

For a given temperature T, the coefficient of variation (COV) of Ft is very low. This shows the time independence of the temperature factors. Table 4.9 presents 

Type Stress (MPa) Temperature ( C) Temperature factor SD of temperature factor COV (%) of temperature factor 

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The concentration of dissolved ionic substances can be roughly estimated by multiplying the specific conductance by an empirical factor of 0.55—0.9, depending on temperature and soluble components. Since specific conductance is temperature dependent, all samples should be measured at the same temperature. Alternatively, an appropriate temperature-correction factor obtained by comparisons with known concentrations of potassium chloride may be used. Instmments are available that automatically correct conductance measurements for different temperatures. 

The mercury barometer (Fig. 10-11) indicates directly the absolute pressure of the atmosphere in terms of height of the mercuiy column. Normal (standard) barometric pressure is 101.325 kPa by definition. Equivalents of this pressure in other units are 760 mm mercury (at 0°C), 29.921 iuHg (at 0°C), 14.696 IbFin, and 1 atm. For cases in which barometer readings, when expressed by the height of a mercuiy column, must be corrected to standard temperature (usually 0°C), appropriate temperature correction factors are given in ASME PTC, op. cit., pp. 23-26 and Weast, Handbook of Chemistty and Physics, 59th ed., Chemical Rubber, Cleveland, 1978-1979, pp. E39-E41. 

The calculation procedure for temperature correction factors won t work for a temperature cross in a single shell pass, but this is an undesirable situation anyway. 

Temperature correction factor, vacuum flow. Figure 2-43... 

TEMPERATURE CORRECTION FACTOR IN % FROM RUPTURE PRESSURE AT 72T. 

If the temperature at the valve inlet is expected to be 50°F, then the temperature correction factor... 

Gravity and Temperature Correction Factors for Low Pressme Venting Calculations for Vapors... 

Chart II Temperature Correction Factors for Maximum Safe Speeds of LS or RIM Wheels... 

Chart III Temperature Corrections Factors for Maximmn Safe Speeds of DH Wheels... 

Figure 12.19. Temperature correction factor one shell pass two or more even tube passes...

Temperature correction factor plots for other arrangements can be found in the TEMA standards and the books by Kern (1950) and Ludwig (2001). Mueller (1973) gives a comprehensive set of figures for calculating the log mean temperature correction factor, which includes figures for cross-flow exchangers. 

The following assumptions are made in the derivation of the temperature correction factor F in addition to those made for the calculation of the log mean temperature difference ... 

Figure 12.20. Temperature correction factor two shell passes four or multiples of four tube passes...

Figure 12.22. Temperature correction factor, split flow shell, 2 tube pass...

When the condensation process is not exactly isothermal but the temperature change is small such as where there is a significant change in pressure, or where a narrow boiling range multicomponent mixture is being condensed the logarithmic temperature difference can still be used but the temperature correction factor will be needed for multipass condensers. The appropriate terminal temperatures should be used in the calculation. 

The temperature correction factor, Ft, will normally be higher with plate heat exchangers, as the flow is closer to true counter-current flow. 

Determine the log mean temperature correction factor, Ft see method given below. 

Figure 12.62. Log mean temperature correction factor for plate heat exchangers (adapted from Raju and Chand (1980))...

The volumetric flow rate of propane at the reactor inlet is given by the product of the molal flow rate, the molal volume of the gas at standard conditions, and the pressure and temperature correction factors implied by the ideal gas law. 

The temperature-time superposition principle is illustrated in Figure 8 by a hypothetical polymer with a TK value of 0°C for the case of stress relaxation. First, experimental stress relaxation curves are obtained at a series of temperatures over as great a time period as is convenient, say from 1 min to 10 min (1 week) in (he example in Figure 8. In making the master curve from the experimental data, the stress relaxation modulus ,(0 must first be multiplied by a small temperature correction factor/(r). Above Tg this correction factor is where Ttrt is the chosen reference... 

Tables have been published relating Baume, Brix and specific gravity. As density is temperature dependent it is necessary to either bring the syrup to a fixed temperature or, as is more common in practice, to use temperature correction factors or tables. The relationship between density and concentration is slightly different for invert sugar or glucose syrups. The Brix scale is sometimes applied to products that are not sucrose syrups, such as concentrated fruit juice. Recipes are certainly in use that state boil to x Brix . In practice these instructions mean that the material should give the same reading as a sugar syrup of that concentration. As often happens in confectionery these practices have been proved to work empirically.

Temperature Correction Factor The rate of the above reaction is temperature dependent. Hence, if the temperature (experimental) is higher or lower than that used to define a unit of activity, a definite correction factor should be applied as per Table 2.10. 

Calibration of thermocouples should be carried out at two temperatures. One of these is an ice-point reference at 0.0°C. The other should be a hot point slightly higher than the expected sterilization temperature. Correction factors are applied at both temperatures and the response of... 

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