Petroleum and related products. Temperature and pressure volume correction factors (petroleum measurement tables) and standard reference conditions

2017 ◽  
2005 ◽  
Vol 76 ◽  
pp. S148
Author(s):  
J. Pena ◽  
F. Sânchez-Doblado ◽  
R. Capote-Noy ◽  
J.A. Terrón ◽  
F. Gómez

Author(s):  
D. Kretschmer ◽  
J. Odgers

In a recent publication [3], the authors tentatively explored the prediction of propane flame speeds using the calculated burned gas temperature (Tb) and the predicted flame extinction temperature (Ti). A formula was developed which utilised the above temperatures together with correction factors for inlet temperature and the oxygen/inert ratio. The present paper has extended this technique so that data from 20 different fuels have been examined over a range of conditions which include significant variations of both inlet temperature and pressure. Limitations of the technique are discussed, as are possible related applications to other premixed systems such as laminar flames and well-stirred reactors.


2019 ◽  
Vol 9 (1Feb) ◽  
Author(s):  
S A Rahimi ◽  
B Hashemi ◽  
S R Mahdavi

Background: Estimating dosimetric parameters for small fields under non-reference conditions leads to significant errors if done based on conventional protocols used for large fields in reference conditions. Hence, further correction factors have been introduced to take into account the influence of spectral quality changes when various detectors are used in non-reference conditions at different depths and field sizes.Objective: Determining correction factors (KNR and KNCSF) recommended recently for small field dosimetry formalism by American Association of Physicists in Medicine (AAPM) for different detectors at 6 and 18 MV photon beams.Methods: EGSnrc Monte Carlo code was used to calculate the doses measured with different detectors located in a slab phantom and the recommended KNR and KNCSF correction factors for various circular small field sizes ranging from 5-30 mm diameters. KNR and KNCSF correction factors were determined for different active detectors (a pinpoint chamber, EDP-20 and EDP-10 diodes) in a homogeneous phantom irradiated to 6 and 18 MV photon beams of a Varian linac (2100C/D).Results: KNR correction factor estimated for the highest small circular field size of 30 mm diameter for the pinpoint chamber, EDP-20 and EDP-10 diodes were 0.993, 1.020 and 1.054; and 0.992, 1.054 and 1.005 for the 6 and 18 MV beams, respectively. The KNCSF correction factor estimated for the lowest circular field size of 5 mm for the pinpoint chamber, EDP-20 and EDP-10 diodes were 0.994, 1.023, and 1.040; and 1.000, 1.014, and 1.022 for the 6 and 18 MV photon beams, respectively.Conclusion: Comparing the results obtained for the detectors used in this study reveals that the unshielded diodes (EDP-20 and EDP-10) can confidently be recommended for small field dosimetry as their correction factors (KNR and KNCSF) was close to 1.0 for all small field sizes investigated and are mainly independent from the electron beam spot size.


Author(s):  
Junjun Chen ◽  
Jingyuan Qu ◽  
Junjun Gong

Before the design of the nuclear facility, it is necessary to estimate the dose caused by radioactive material released into the environment during the course of the serious accidents. Semi-infinite hemisphere geometric model is established to estimate the personal external exposure dose outdoors in which the distribution of the nuclides is assumed to be uniform. The exposed staffs are in a limited cubic space when using this model to evaluate the controllability of the main control room. Thus, the volume correction factor is needed to correct the dose, whose traditional expression is f = 352/pow(V, 0.338). The formula cannot satisfy the requirement of higher accuracy due to the neglect of the influence of the shape of geometric model and γ-rays energy. Usually the actual control room is a cube and the γ-rays energies emitted from various nuclides are different. In order to calculate the accurate volume correction factor of main control room under different geometric conditions, a finite cubic geometric model is established in this paper. The length and width of the model are between 6m and 50 m, the height is between 4m and 6m, and γ-ray energy respectively are 0.05, 0.2, 0.733, 1.2 and 3 MeV, respectively. The effective volume values for different conditions are calculated by the Monte-Carlo program, and 318 groups of results are obtained. The calculated volume dose rate of 360m × 360m × 255m (assuming semi-infinite) cube at 733keV γ-rays energy is taken as a criterion, whose ratio of the other calculation results is the new volume correction factor value. By comparing two volume correction factors, the relative discrepancies are within 3 folds, proving that the calculation result is reasonable and feasible. The new volume correction factor varies with γ-rays energy and the shape of the geometric model. A neural network model corresponding to the volume correction factor is developed to apply to more cases. 80% of the results are randomly selected as the training set of neural network. The remaining 20% of the result as the test set of the cross-test is to predict the results of the trained neural network, whose relative errors are less than 5%. The neural network model can obtain the volume correction factor under different geometry and γ-ray energy conditions. Finally, a volume correction factor library is established, which can provide a powerful reference to obtain the volume correction factor of the limited space model such as the main control room.


2002 ◽  
Vol 66 (6) ◽  
pp. 1021-1028 ◽  
Author(s):  
P. McDade ◽  
B. J. Wood ◽  
W. Van Westrenen ◽  
R. Brooker ◽  
G. Gudmundsson ◽  
...  

Abstract Piston-cylinder cell assemblies experience inhomogeneous pressure distribution upon pressurization due to the variable compressibilities of the cell components. This results in the sample experiencing a pressure lower than expected, given the applied force of the piston. Although the effect is generally compensated for by applying a ‘friction’ correction, there have been wide variations in the corrections applied for some of the harder cell materials. We have determined friction correction factors for a range of cell assemblies commonly used in our laboratory relative to select well-characterized phase equilibria. Single-sleeve NaCl cells require, using the piston-in technique, very small corrections of the order −0.05 GPa for 12.7 mm diameter, and less for larger diameter assemblies. Four separate calibrations of the single sleeve 12.7 mm BaCO3 cell show that it requires a correction of −9%. This factor is entirely independent of temperature and pressure within the range 1000 to 1600°C and 1.5 to 3.2 GPa. This result is in contrast to the results of Fram and Longhi (1992) who claim that the correction for BaCO3 cells is highly dependent on pressure. For the assemblies included in this study there is an increase in the pressure correction required in the order of 12.7 mm diameter NaCl-pyrex −3%; 19 mm talc-pyrex −3.6%; 12.7 mm BaCO3 −9% and 12.7 mm BaCO3-silica glass −13%.


1976 ◽  
Author(s):  
J. W. Marzeski ◽  
W. S. Blazowski

Recent investigations have indicated that aircraft engine exhaust emissions are sensitive to ambient conditions. This paper reports on combustor rig testing intended to evaluate variations due to ambient temperature and pressure with special emphasis on idle engine operating conditions. Empirically determined CO, CxHy, and NOx correction factors — the ratio of the pollutant emission index value obtained during standard day operation to that resulting during actual ambient conditions — are presented. The effects of engine idle cycle pressure ratio, primary zone fuel-air ratio, and fuel type were investigated. Ambient temperature variations were seen to cause substantial emission changes; correction factors in excess of 2.0 were determined in some cases. Ambient pressure variations were found to be less substantial. A previously published NOx emission model and a simplified hydrocarbon combustion analysis are shown to be in general agreement with the empirical results.


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