scholarly journals Advanced Determination of Heat Flow Density on an Example of a West Russian Oil Field

Geosciences ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 346
Author(s):  
Yury Popov ◽  
Mikhail Spasennykh ◽  
Anuar Shakirov ◽  
Evgeny Chekhonin ◽  
Raisa Romushkevich ◽  
...  

Reliable geothermal data are required for basin and petroleum system modeling. The essential shortcomings of the methods and results of previous geothermal investigations lead to a necessity to reappraise the data on the thermal properties and heat flow. A new, advanced experimental basis was used to provide reliable data on vertical variations in the thermal properties of formation and heat flow for the area surrounding a prospecting borehole drilled through an unconventional hydrocarbon reservoir of the Domanik Formation in the Orenburg region (Russia). Temperature logging was conducted 12.5 months after well drilling. The thermal properties of the rocks were measured with continuous thermal core profiling on all 1699 recovered core samples. Within non-cored intervals, the thermal conductivity of the rocks was determined from well-logging data. The influence of core aging, multiscale heterogeneity and anisotropy, in situ pressure and temperature on the thermal properties of rock was accounted for. The terrestrial heat flow was determined to be 72.6 ± 2.2 mW·m−2—~114% larger than the published average data for the studied area. The experiment presents the first experience of supporting basin modeling in unconventional plays with advanced experimental geothermal investigations.

2018 ◽  
Vol 26 (1(127)) ◽  
pp. 120-124
Author(s):  
Iwona Frydrych ◽  
Goran Demboski

The paper investigates the influence of fabric structure variations and finishing on the thermal properties of woven fabrics for a tailored garment. Four distinctive pairs of fabrics were investigated, where the weft density, weft yarn count or type and finishing were varied within the fabrics in each pair. Several thermal properties such as conductivity, diffusivity, absorptivity, resistance, the ratio of maximal and stationary heat flow density and the stationary heat flow density were measured using an Alambeta device. The results obtained showed that variation of the weft yarn count and finishing have a significant effect on several thermal properties. Increasing the weft count increased the thermal conductivity, absorptivity, resistance and the ratio of maximal and stationary heat flow density. The application of oilproof and waterproof finishing affected thermal diffusivity, thermal absorptivity and thermal resistance. Milled finishing contributed to increasing the thermal resistance.


Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6863
Author(s):  
Desalegn Atalie ◽  
Pavla Tesinova ◽  
Melkie Getnet Tadesse ◽  
Eyasu Ferede ◽  
Ionuț Dulgheriu ◽  
...  

Consumers expect high-performance functionality from sportswear. To meet athletic and leisure-time activity requirements, further research needs to be carried out. Sportswear layers and their specific thermal qualities, as well as the set and air layer between materials, are all important factors in sports clothing. This research aims to examine the thermal properties of sports fabrics, and how they are affected by structure parameters and maintained with different layers. Three inner and four outer layers of fabric were used to make 12 sets of sportswear in this study. Before the combination of outer and inner layers, thermal properties were measured for each individual layer. Finally, the thermal resistance, thermal conductivity, thermal absorptivity, peak heat flow density ratio, stationary heat flow density, and water vapor permeability of bi-layered sportswear were evaluated and analyzed. The findings show that sportswear made from a 60% cotton/30% polyester/10% elastane inner layer and a 100% polyester outer layer had the maximum thermal resistance of 61.16 (×103 K·m2 W−1). This performance was followed by the sample made from a 90% polyester/10% elastane inner layer and a 100% polyester outer layer, and the sample composed of a 100% elastane inner layer and a 100% polyester outer layer, which achieved a thermal resistance value of 60.41 and 59.41 (×103 K·m2 W−1), respectively. These results can be explained by the fact that thicker textiles have a higher thermal resistance. This high-thermal-resistance sportswear fabric is appropriate for the winter season. Sportswear with a 90% polyester/10% elastane inner layer had worse water vapor resistance than sportswear with a 60% cotton/30% polyester/10% elastane and a 100% elastane layer. Therefore, these sports clothes have a higher breathability and can provide the wearers with very good comfort. According to the findings, water vapor permeability of bi-layered sportswear is influenced by geometric characteristics and material properties.


1986 ◽  
Vol 23 (9) ◽  
pp. 1257-1264 ◽  
Author(s):  
K. Wang ◽  
P. Y. Shen ◽  
A. E. Beck

In heat flow determinations, it is customary to treat the surface temperature variation as a finite sum of Fourier components. The medium is assumed to be homogeneous or horizontally stratified with each layer having a constant conductivity and diffusivity. This allows the effect of each periodic component to be calculated analytically. We extend this formulation to include cases where thermal conductivities in some layers of a stratified medium may vary linearly with depth as have been found in the sediments of some continental lakes. The application of this formalism to temperature measurements in Lake Greifensee and Lac Leman shows that even with excellent records of bottom temperature variations over several years, failure to take into account the conductivity variation leads to errors as high as 20% in heat flow density values, depending on the depth interval used. The combined effects of lack of detailed knowledge of conductivity structure and the use of too short and (or) inaccurate records of bottom temperature variations, leading to very significant errors, are also discussed, with particular reference to the problems arising from a lack of recognition of the existence of nonannual terms in the bottom temperature variation and the use of probes that do not penetrate the sediments deeply enough.


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