scholarly journals Sensitivity analysis of temperature field in the heated soft tissue with respect to the perturbations of porosity

2017 ◽  
Vol 49 ◽  
pp. 498-513 ◽  
Author(s):  
Grażyna Kałuża ◽  
Ewa Majchrzak ◽  
Łukasz Turchan
Keyword(s):  
Sensitivity Analysis ◽  
Temperature Field ◽  
Soft Tissue

scholarly journals Evolution regularity of temperature field of active heat insulation roadway considering thermal insulation spraying and grouting: A case study of Zhujidong Coal Mine, China

2021 ◽  
Vol 40 (1) ◽  
pp. 151-170
Author(s):  
Weijing Yao ◽  
Happiness Lyimo ◽  
Jianyong Pang
Keyword(s):  
Sensitivity Analysis ◽  
Temperature Field ◽  
Thermal Insulation ◽  
Wall Temperature ◽  
Heat Insulation ◽  
Surrounding Rock ◽  
Rock Temperature ◽  
Grouting Materials ◽  
Zone Radius ◽  
Thermal Conductivities

Abstract To study the active heat insulation roadways of high-temperature mines considering thermal insulation and injection, a high-temperature −965 m return air roadway of Zhujidong Coal Mine (Anhui Province, China) is selected as a prototype. The ANSYS numerical simulation method is used for the sensitivity analysis of heat insulation grouting layers with different thermal conductivities and zone ranges and heat insulation spray layers with different thermal conductivities and thicknesses; thus, their effects on the heat-adjusting zone radius, surrounding rock temperature field, and wall temperature are studied. The results show that the tunneling head temperature of the Zhujidong Mine is >27°C all year round, consequently causing serious heat damage. The heat insulation circle formed by thermal insulation spraying and grouting can effectively alleviate the disturbance of roadway airflow to the surrounding rock temperature field, thereby significantly reducing the heat-adjusting zone radius and wall temperature. The decrease in the thermal conductivities of the grouting and spray layers, expansion of the grouting layer zone, and increase in the spray layer thickness help effectively reduce the heat-adjusting zone radius and wall temperature. This trend decreases significantly with the ventilation time. A sensitivity analysis shows that the use of spraying and grouting materials of low thermal conductivity for thermal insulation is a primary factor in determining the temperature field distribution, while the range of the grouting layer zone and the spray layer thickness are secondary factors. The influence of the increased surrounding rock radial depth and ventilation time is negligible. Thus, the application of thermal insulation spraying and grouting is essential for the thermal environment control of mine roadways. Furthermore, the research and development of new spraying and grouting materials with good thermal insulation capabilities should be considered.

Modeling of Laser-Soft Tissue Interactions Using the Dual-Phase Lag Equation: Sensitivity Analysis with Respect to Selected Tissue Parameters

2017 ◽  
Vol 379 ◽  
pp. 108-123
Author(s):  
Ewa Majchrzak ◽  
Marek Jasiński ◽  
Łukasz Turchan
Keyword(s):  
Sensitivity Analysis ◽  
Soft Tissue ◽  
Laser Irradiation ◽  
Soft Tissues ◽  
Initial Conditions ◽  
Internal Heat ◽  
Bioheat Transfer ◽  
Phase Lag ◽  
Dual Phase ◽  
Coupled Equations

Thermal processes occurring in soft tissues are subjected to laser irradiation are analyzed. The transient bioheat transfer is described by the generalized dual-phase lag model. This model consists of two coupled equations concerning the tissue and blood temperatures supplemented by the appropriate boundary and initial conditions. The efficiency of the internal heat source connected to the laser irradiation results from the solution of the diffusion equation. This approach is acceptable when the scattering dominates over the absorption for wavelengths between 650 and 1300 nm, and just such a situation occurs in the case of soft tissues. Sensitivity analysis with respect to the parameters occurring in the mathematical model is done using the direct approach (differentiation of the basic equations and the boundary-initial conditions with respect to the parameter considered), especially the absorption coefficient and scattering coefficient of the soft tissue are considered. At the stage of numerical modeling the basic problem and additional problems connected with the sensitivity functions are solved using the finite difference method. In the final part the conclusions and examples of computations are presented.

scholarly journals The Influence of Pin Deviation on the Fracture Correction and the Fixator Adjustment with Sensitivity and Kinematic Analysis

2018 ◽  
Vol 2018 ◽  
pp. 1-16
Author(s):  
Xia Zhao ◽  
Jianfeng Li
Keyword(s):  
Sensitivity Analysis ◽  
Soft Tissue ◽  
External Fixator ◽  
Clinical Case ◽  
Operation Time ◽  
Inverse Kinematic ◽  
Evaluation Index ◽  
Kinematic Method ◽  
Orientation Deviation ◽  
The Impact

Fracture correction is important orthopedics operation and can be performed by unilateral external fixator. Due to pin deviations being inevitable during the operation, searching the impacts of pin deviation on the fracture correction and fixator joint adjustment are important. This study puts forward evaluation index with sensitivity analysis for investigating the impact of three orientation deviations and three position deviations on fracture correction. Meanwhile, based on a clinical case from a 28-year-old female, the influence of pin deviation on the adjustment of fixator joints was analyzed by inverse kinematic method. Different pin deviations have different sensitivity; the sensitivity of orientation deviation is relatively larger than position deviation. The existence of pin deviation will result in the change of the adjustment value of fixator joints. In addition, the experiments of seven situations were established to verify the analytical results. This study revealed the sensitivity of different pin deviations which can also be used to predict the adjustment value of fixator joints and the accuracy of fracture correction. This research also helps to reduce operation time and decrease damage to soft tissue by reducing the frequency of inserting pins.

Sign in / Sign up

Export Citation Format

Share Document