Mobile Refuge Chamber Research Articles

Failure Mode Analysis and Dynamic Response of a Coal Mine Refuge Chamber with a Gas Explosion

A gas and coal dust explosion is potential hazard in majority coal mines. A coal mine mobile refuge chamber is a new class of device for miners those who are unable to escape after an accident which can provide basic survival conditions. In this paper, in order to study the propagation law of an underground methane/air mixture explosive wave, and check the failure mode of a coal mine mobile refuge chamber, a full-sized underground tunnel model and a refuge chamber model have been established in ANSYS/LS-DYNA (LSTC, R7.0.0, Livermore, CA, USA, 2014). The simulation results show that the reflected wave pressure on the front surface of the refuge chamber was about twice as high than the incident wave. The pressure on various locations of the chamber was also analyzed. When the peak pressure of the explosive shockwave reached 0.64 MPa, the maximum displacement and stress occur at the center of the front door and the joint of stiffeners and the front plate, respectively. Most parts of the coal mine mobile refuge chamber were in a plastic failure state and the refuge chamber could be defined as damaged. The front door, the front plate, the connecting flange, and the stiffeners on each side were the primary key components. In the end, suggestions were proposed for the refuge chamber.

Comparison of Static and Dynamic Analysis on KJYF96/8 Mobile Refuge Chamber

This paper studied the difference between the static analysis and dynamic analysis on the mobile refuge chamber. The structure strength static analysis of KJYF96/8 mobile refuge chamber was made by the finite element software SolidWorks Simulation and the stress cloud chart and the displacement cloud chart were obtained. The corresponding relation between the dynamic analysis result and the static analysis result was obtained based on the comparison with the result of the dynamic analysis. The results indicate that the values of the max stress and displacement by static analysis with a uniform external pressure of the dynamic pressure peak value are greater than those by dynamic analysis. And the weighting method of static analysis can be used in the coal mine mobile refuge chamber structure design process instead of dynamic analysis.

The Segment Loading Static Finite Element Analysis on the Mobile Refuge Chamber

This paper studied the difference between the segment loading static analysis method and the uniform loading static analysis method on the mobile refuge chamber. The structure strength static analysis of the mobile refuge chamber was made in the uniform and segment loading ways by the finite element software SolidWorks Simulation. The stress cloud charts and the displacement cloud charts were obtained. The comparison result indicates that the results of the segment loads method are less than those of the uniform loading method and is closer to those of the dynamic analysis method. Therefore the segment loading static analysis method is better than the uniform loading one.

Pressure characteristics and dynamic response of coal mine refuge chamber with underground gas explosion

Coal mine refuge chambers are new devices for coal mine safety which can provide basic survival conditions after gas explosion. In order to simulate the propagation of underground methane/air mixture blast wave, and check structural safety of coal mine mobile refuge chamber, an underground tunnel model and a refuge chamber model have been established based on explicit nonlinear dynamic ANSYS/LS-DYNA 970 program. Results show that the reflected wave pressure on the impact surface was about two times higher than that on the incident one. The relationship between the pressure fields of the chamber was analyzed. The maximum pressure of gas explosion reached about 0.71 MPa, and the pulse width was 360 ms. The maximum absolute displacement and stress occurs at the main door center and the connection of stiffeners and the front plate, respectively. The entire coal mine mobile refuge chamber was in elastic state and its strength and stiffness meet the safety requirements. The cabin door, the front plate and the connecting flange at cabin back as well as the stiffeners on each side were the most critical components. Suggestions were put forward for the refuge chamber.

Structural Design and Analysis of the New Mobile Refuge Chamber

At present, the mobile refuge chambers are mostly used square or circular structures. Based on these researches, a new chamber structure is presented in this paper, which is square and circular combined structure. The size and connection way are designed through the analysis of the working conditions and the requirements of the installation, transportation, maintenance and so on. Then the new structure is simplified to four kinds of cabin model, which can be analyzed by the ANSYS software. By the simulation analysis the reliability of the new structure is determined, which provides a theoretical basis for guiding the structural design of the mobile refuge chamber.

Test Research for Thermal Protective Properties of Mobile Refuge Chamber

In this paper we have a discussion on heat insulation method of the using of mobile refuge chamber for coal mine and the improved scheme was put forward to improve the performance of thermal protective properties of the refuge chamber. Then according to the theoretical analysis and the external heating test methods to be compared,we conduct an analysis.The test method are introduced, and the factors caused the temperature changes are analyzed based on the test.These results have directive significance for the further improvement of refuge chambers.

Design Scheme of Outside Environmental Monitoring System for Coal Mine Mobile Refuge Chamber

The paper mainly introduced research state of coal mine mobile refuge chamber and its outside environmental monitoring system, analyzed particularity of chamber-outside environment and design requirements of outside environmental monitoring system for coal mine mobile refuge chamber, and put forward design goals and idea of software design, hardware design and protective device of outside environmental monitoring system for coal mine mobile refuge chamber. It put forward a design scheme of outside environmental monitoring system for coal mine mobile refuge chamber according to the actual applications and design goals. The design scheme consists of software, hardware and protective device. And it detailed expounded environmental monitoring system’s working principle, signal transmission principle and workflow. The paper can provide technology reference for development of outside environmental monitoring system for coal mine mobile refuge chamber in China.

Coal Mine Mobile Refuge Chamber with Square Cross Section Structure Finite Element Analysis

Coal mine mobile refuge chamber, as the important equipment of underground refuge system, has a close relation to the life safety of the miners. At present, there are a lot of production refuge Chamber manufacturers, but they do not enjoy a unified standard in shape or size. This paper focuses on the establishment of the KJYF96/10 mobile refuge chamber model by Solidworks and adopts the structural finite element analysis by Simulation, drawing a conclusion of refuge chamber stress and displacement cloud chart. It is expected to offer an effective reference to improving the structure strength and reducing design costs.

Simulation Analysis on Structure Safety of Two Typical Refuge Chamber Shell Forms Under Explosion Load

Abstract In order to reduce the risk of sealing and improve the structural strength safety for coal mine mobile refuge chamber, two models with certain proportion were set up after mechanical analysis. One was one-piece coal mine mobiles refuge chamber form which involves less sealing problems between sections, the other was segmented coal mine mobiles refuge chamber form which is easy to transport. A simulation analysis method was used to confirm their structure safety. Verified finite element analysis method was used to simulate the responses under blast loading. Considering the harsh conditions, the maximum pressure of the triangle impact load was 0.8 MPa, and the pulse width was 300ms. The maximum stress of one-piece one is less than segmented one. It demonstrated that section connecting position can cause more stress concentration. The maximum displacement one of one-piece is more than segmented one. It demonstrated that segmented type had lower displacement. Weak part of one-piece was middle position of front and back end shell. Weak parts of segmented type were middle position of sides and section connecting position. Based on their weak places analyzed, suggestions were put forward for the two kinds. Arc structure might be used in the front and back end shell. The front and back end shell might be thickened. Only inclined shaft with larger wellhead is suitable for this type. Segmented type could be used in large or medium-sized one.

Simulation analysis on structure safety of coal mine mobile refuge chamber under explosion load

In order to check structural strength of coal mine mobiles refuge chamber, and do security evaluation of the mobile refuge chamber, a refuge chamber model was established, then a finite element method was instituted for it to ensure the refuge chamber would not be severely damaged when gas or coal dust explosion suddenly happened. A triangle shock wave with 1.2MPa over-pressure, 300ms lasting time was settled. Explicit nonlinear dynamic analysis program was used to simulate response of the refuge chamber. The maximum stress was 244MPa, located in central part of sides and tail end of the last capsule. The maximum displacement was 29.32mm, located in central part of sides and tail end of the last capsule. The calculation indicated that the refuge chamber was not obviously damaged. It could reliable work to meet safety requirements. Compared with the reported experimental results, the simulation method was verified. Based on analysis, suggestions were put forward for further improving.

Analysis on Effect of Heat Bridge to Heat Transfer of Refuge Chamber’s Shell

In order to improve the heat-insulating capability of the refuge chamber’s shell and reduce energy consumption of the cooling system, the horizontal cylindrical mobile refuge chamber for coal mine was taken as the research object. By selecting two connection types between the inner shell and the outer shell for calculation, which were direct connection type and indirect connection type, and comparing these with the connectionless heat transfer, the heat transfer process in the refuge chamber subjected to thermal loadings of constant temperature was respectively discussed with numerical analysis method. Effect of heat bridges to heat transfer of the refuge chamber’s shell was analyzed. The analysis results showed that the average heat flux through direct connection heat bridge and indirect connection heat bridge had respectively increased by 668% and 30% than that of the connectionless heat transfer. The influencing scope of the former was larger than the latter’s. And more heat entered the refuge chamber through the direct connection heat bridge. Therefore, the indirect connection type should be used in the design of the refuge chamber’s shell.