Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "coal seam" wg kryterium: Temat


Wyświetlanie 1-3 z 3
Tytuł:
Determination of stress state in coal seam based on inverse problem solution using acoustic sounding data
Autorzy:
Kudaibergenov, Mels K.
Iskakov, Kazizat T.
Kudaibergenova, Bakytzhan S.
Powiązania:
https://bibliotekanauki.pl/articles/88885.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:
coal seam
stress
elasticity theory
biharmonic equation
inverse problem
Opis:
The paper presents an algorithm for calculating the horizontal, vertical and tangential stresses in a horizontal coal seam lying between galleries. These stresses are expressed in terms of the Airy function, which satisfies a homogeneous biharmonic equation. For its numerical solution it is necessary to set boundary conditions. Practical limitations do not allow us to determine the tangential stresses on horizontal boundaries of the coal seam. Calculations of stresses are proposed to be carried out in two steps. The first step is to solve the inverse problem for the biharmonic equation to find unknown tangential stresses on horizontal boundaries of the coal seam. The inverse problem is solved by minimizing the residual functional. Its strong convexity is proved, which implies the existence and uniqueness of the solution of the inverse problem. The second step is to solve the boundary value problem for the biharmonic equation to calculate stresses in the coal seam. The result of a numerical experiment is presented.
Źródło:
Mining Science; 2019, 26; 173-187
2300-9586
2353-5423
Pojawia się w:
Mining Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of the impact of exploitation structures on pressure distribution and adsorbed methane content in coal seams using dynamic flow models. A case study
Autorzy:
Szott, Wiesław
Miłek, Krzysztof
Łętkowski, Piotr
Gołąbek, Andrzej
Powiązania:
https://bibliotekanauki.pl/articles/1402316.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:
methane drainage
coal seam
exploitation structures
desorption
reservoir simulation
Opis:
One of the most serious difficulties encountered during the estimation of results of various methods of methane drainage from coal seams is the determination of the initial condition of the analysed coal seam prior to commencement of the actual process of methane drainage. It is well known that the exploitation operation in adjacent coal seams, as well as preparatory works in the analysed seam may significantly modify the original state of methane adsorption in that seam, as well as influence the distribution of pore pressure and saturation of its natural fractures with fluids (gas, water). This state is of dynamic nature and depends on a long and complex history of the mining activity in the analysed facility and its surrounding. Detailed specification of the above condition is usually replaced by qualitative and very approximate models, which does not allow for consideration of the process preceding the methane drainage. The subject of the paper is the quantitative evaluation of the initial conditions for a coal seam with the use of dedicated simulation models of the analysed seam along with its broad surroundings. Results of this modelling including modifications of appropriate transport parameters of layers between the seams and their influence on detailed distribution of pore pressures, levels of methane desorption from the coal matrix, directions of reservoir fluids flow (methane, water) and saturation with these fluids in natural fractures of the selected seam, as well as in the pores of overburden and underburden rocks will be thoroughly analysed for determination of spacious and temporal effects of the mining activities in terms of their influence on the selected seam.
Źródło:
Mining Science; 2020, 27; 133-153
2300-9586
2353-5423
Pojawia się w:
Mining Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Finite element analysis of load characteristic of shield bolter miner cutting head under complex coal seam condition
Autorzy:
Qiao, S.
Xia, Y. M.
Liu, Z. Z.
Liu, J. S.
Ning, B.
Wang, A. L.
Powiązania:
https://bibliotekanauki.pl/articles/89071.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:
complex coal seam
shield bolter miner
load characteristic
specific energy
load fluctuation
Opis:
Aiming at the complex conditions of the first shielded bolter miner in the actual work, the mechanical model of bolter miner cutting head was established. Based on cutting mechanism of the conical pick and the cutting head, the cutting head load and torque analysis model under complex coal seam were established. The dynamic characteristics of load and torque in the process of cutting head are analyzed under three different working conditions of cutting roof-coal layers, coal-floor layers and coal seam by finite element method. The results show that when the damage variable D=1, the coal-rock completely lacks the bearing capacity, and it forms arc-shaped crushing groove on the coal-rock. The large difference of torque between roof-coal layers and the roof-coal layers in the conical pick is 112 Nm, which indicates that the cutting head has the best performance with cutting the coal seam first and then cutting the rock. In the process of excavation, the load fluctuation coefficient of cutting the coal-floor layers and roof-coal layers is about 1.2 times of that of the coal seam. The results can provide a reference for the efficient cutting and performance evaluation of the bolter miner.
Źródło:
Mining Science; 2017, 24; 85-97
2300-9586
2353-5423
Pojawia się w:
Mining Science
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-3 z 3

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies