A Note on the Theory of Temperature Logging

1969 ◽  
Vol 9 (04) ◽  
pp. 375-377 ◽  
Author(s):  
Antonio Romero-Juarez
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Heat Transfer Coefficient ◽  
Flux Line ◽  
Water Injection ◽  
Constant Heat Flux ◽  
Constant Heat ◽  
Injection Wells ◽  
Theoretical Considerations ◽  
Great Step

Interest in temperature logs has been renewed recently. One of the main problems of temperature logs in injection wells is that of determining the zones that are taking fluids. A great step toward solving this problem has been reported in a recent paper. paper. The purpose of this paper is to point out another aim of temperature logging namely, that of relating the flow rate in water injection wells to some characteristics of the temperature logs. It has been stated that a factor of 6:1 gives approximate values in converting into B/D. The factor F, which has been found empirically, may be explained from theoretical considerations and because of this, it may be estimated more accurately. It has been shown that, for flow of a liquid ,............................(1) where .......................(2) a quantity that is different from zero. Eq. 1 can be written as ,..................................(3) which shows that, as is defined in Ref. 2, is identical to A. For injection down casing, the over-all heat transfer coefficient, U, may be considered infinite. Therefore, ...................................(4) Considering the wellbore as a linear point source, ....................(5) or, if ........................................(6) .......................(7) It has been observed that surprisingly good results are obtained by using the values k = 33.6 Btu/day-ft-F and a = 0.96 sq ft/day for different locations. Taking the values p = 350 lb/bbl, c = 1 Btu/lb-F, one obtains: ........................(8) It should be noted that the lower curve of Fig. 1 of Ref. 3 does not agree, for low values of t, with the solution .........................(9) corresponding to the constant heat flux line source and for this reason the graph should be used with caution. Eq. 8 has been plotted in Fig. 1 for three values of the external radius r'. It may be used to estimate the rate of water injection down casing from the shape of the injecting temperature log above the zone of entry of fluids. P. 375

Heat Transfer Characteristics of CuO-Base Oil Nanofluid Laminar Flow Inside Flattened Tubes Under Constant Heat Flux

2010 ◽  
Author(s):  
P. Razi ◽  
M. A. Akhavan-Behabadi
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Constant Heat Flux ◽  
Electrical Heating ◽  
Heat Transfer Characteristics ◽  
Constant Heat ◽  
Base Oil ◽  
Transfer Characteristics

An experimental investigation has been carried out to study the heat transfer characteristics of CuO-Base oil nanofluid flow inside horizontal flattened tubes under constant heat flux. The nanofluid flowing inside the tube is heated by an electrical heating coil wrapped around it. The convective heat transfer coefficients of nanofluids are obtained for laminar fully developed flow inside round and flattened tubes. The effect of different parameters such as Reynolds number, flattened tube internal height, nanoparticles concentration and heat flux on heat transfer coefficient is studied. Observations show that the heat transfer performance is improved as the tube profile is flattened. The heat transfer coefficient is increased by using nanofluid instead of base fluid. Also, it can be concluded that decreasing the internal height of the flattened tubes and increasing the concentration of nanoparticles both contribute to the enhancement of heat transfer coefficient.

Experimental Investigation of Heat Transfer to Nanofluids

2008 ◽  
Author(s):  
Klaudia Chmiel-Kurowska ◽  
Grzegorz Dzido ◽  
Andrzej Gierczycki ◽  
Andrzej B. Jarze˛bski
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Experimental Investigation ◽  
Heat Transfer Coefficient ◽  
Ethylene Glycol ◽  
Constant Heat Flux ◽  
Experimental Investigations ◽  
Average Heat Transfer Coefficient ◽  
Constant Heat ◽  
Average Heat

Experimental investigations of convective heat transfer in nanofluid based on the Cu (approx. 0.15% and 0.25% vol.) nanoparticles synthesized in polyol process were conducted at constant heat flux conditions. A 30% increase in average heat transfer coefficient was found against the results obtained for a pure host liquid (ethylene glycol). Even more significant increase was in the entrance region.

Numerical investigation of CuO-water nanofluid turbulent convective heat transfer in square cross-section duct under constant heat flux

2016 ◽  
Vol 33 (6) ◽  
pp. 1714-1728 ◽  
Author(s):  
Hsien-Hung Ting ◽  
Shuhn-Shyurng Hou
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Convective Heat Transfer ◽  
Cross Section ◽  
Convective Heat ◽  
Constant Heat Flux ◽  
Constant Heat ◽  
Content Type

Purpose – The purpose of this paper is to numerically investigate the convective heat transfer of water-based CuO nanofluids flowing through a square cross-section duct under constant heat flux in the turbulent flow regime. Design/methodology/approach – The numerical simulation is carried out at various Peclet numbers and particle concentrations (0.1, 0.2, 0.5, and 0.8 vol%). The finite volume formulation is used with the semi-implicit method for pressure-linked equations algorithm to solve the discretized equations derived from the partial nonlinear differential equations of the mathematical model. Findings – The heat transfer coefficients and Nusselt numbers of CuO-water nanofluids increase with increases in the Peclet number as well as particle volume concentration. Also, enhancement of the heat transfer coefficient is much greater than that of the effective thermal conductivity at the same nanoparticle concentration. Research limitations/implications – Simulation of nanofluids turbulent forced convection at very high Reynolds number is worth for further study. Practical implications – The heat transfer rates through non-circular ducts are smaller than the circular tubes. Nevertheless, the pressure drop of the non-circular duct is less than that of the circular tube. This study clearly presents that the nanoparticles suspended in water enhance the convective heat transfer coefficient, despite low volume fraction between 0.1 and 0.8 percent. Adding nanoparticles to conventional fluids may enhance heat transfer performance through the non-circular ducts, leading to extensive practical applications in industries for the non-circular ducts. Originality/value – Few papers have numerically studied convective heat transfer properties of nanofluids through non-circular ducts. The present numerical results show a good agreement with the published experimental data.

scholarly journals Heat transfer coefficient in elliptical tube at the constant heat flux

2019 ◽  
Vol 23 (Suppl. 4) ◽  
pp. 1323-1332
Author(s):  
Stanislaw Lopata ◽  
Pawel Oclon ◽  
Tomasz Stelmach ◽  
Pawel Markowski
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Cross Section ◽  
Measurement Data ◽  
Constant Heat Flux ◽  
Working Fluid ◽  
Constant Heat ◽  
The Heat Transfer Coefficient

Cross-flow heat exchangers with elliptical tubes are often used in industrial application. In comparison with round tubes, the elliptical tubes have a better aero-dynamic shape, which results in a lower pressure drop of working fluid flowing through the inter-tubular space of heat exchanger. Also, a higher heat flux is transferred from gas to the wall of such a tube due to the more intense heat exchange process. To prove this thesis, the values of the heat transfer coefficient from the wall of the elliptical pipe to the water flowing inside were determined, using the data from the conducted measurements. This study presents also research stand with a vertically positioned tube. In order to obtain a constant heat flux through the wall of elliptical tube, a resistance wire is used, evenly wound on the external surface of tube measuring section. The use of thermal insulation minimized heat loss to the environment to a negligible value. Installed K-type thermocouples allowed one to obtain, for various measurement conditions, the temperature distribution within the elliptical tube wall (for a given cross-section) and the water flowing inside it (in a given cross-section, at different depths, for both axes of the ellipse). The design of the stand allows such measurements in several locations along the length of the measurement section. The measurement results were used to verify numerical calculations. The relative error of the heat transfer coefficient value determined on the basis of CFD calculations using the SST-TR turbulence model in relation to the one determined on the basis of the measurement data is about 11%.

Sign in / Sign up

Export Citation Format

Share Document