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The coupling effect of seepage and temperature fields in fractured rock mass is a hot topic in the area of water conservancy, nuclear waste disposal and geothermal resources development. A coupling mathematical model of the seepage, flow temperature and rock mass temperature fields in the fracture network of rock mass is established based on the seepage and temperature interaction. A calculation program is developed and applied to calculate the seepage and temperature fields of the dam foundation of a water conservancy project. The interaction mechanism of the seepage, flow temperature and rock mass temperature fields is analyzed in this paper. Results show that the seepage field largely influences the temperature field, which can provide several suggestions for the deep underground disposal of nuclear waste, geothermal resources development and fractured rock mass in dam foundations. Considering the coupling effect of the seepage, flow temperature and rock mass temperature fields by the fracture network method is necessary.

The friction of two bodies in relative motion is accompanied by several phenomena such as elevation of temperature. The aim of this work is to calculate the braking temperature of the brake disc of an aircraft during the landing phase, using a calculation code based on Finite Element Method (FEM) and the analytical method of Newcomb. This investigation uses two kinds of disc — full and real disc (original version mounted on the aircraft) — and three braking disc materials such as the cast irons FG15, FG20 and FG25. The result showed that the numbers of holes and slots existing in the real disc has no influence on the braking temperature compared to the full disc. On the other hand, all brake disc materials have almost the same thermal behavior. Both models, analytical and numerical, provided acceptable results.

Interfaces between polymers and ceramics or metals have wide applications in mechanical, electronic and chemical engineering. Loading speed and temperature have certain influence on interface properties, which affect their application in the service environment. In this paper, the interface intrinsic strength of polypropylene (PP)/silicon oxide (SiO${}_2)$ and polyethylene (PE)/aluminum are studied based on molecular dynamic (MD) tensile method at low temperature and loading speed first. Then changes of interface properties are studied by increasing loading speed and temperature, respectively. The results indicate that interface strength increases or decreases with increasing loading speed or temperature. The interface damage mechanism related to the evolution of free volume is revealed.

In order to better understand, describe and design the interfacial properties of pipe joints for pipeline structures in actual projects, this paper theoretically investigated the mechanical properties of adhesively bonded pipeline joint interface under simultaneous actions of axial tensile loading and temperature changes based on the bilinear rigid-softening constitutive model. Analytical solutions for interface relative slips, shear stresses and load-displacement relationship, as well as expressions for ultimate loads and effective bonding lengths, were derived. Different failure processes including softening or debonding stages caused by the bonding lengths were discussed, demonstrating the full-ranged interfacial failure of pipeline joints and explaining their stress transfer mechanism, interface crack propagation and ductile behavior. The finite element analysis for certain cases was also checked to coincide with the solutions. This helps establish a theoretical analysis basis for the application of pipeline joints in actual environments with loading and temperature differences.

This paper presents a hybrid approach to enhance heat transfer (HT) within a copper square duct for gas turbine (GT) blade cooling systems. The proposed method combines the gannet optimization algorithm (GOA) with the Spiking Deep Residual Network (SDRN), referred to as the GOA–SDRN technique. Since GTs operate at temperatures exceeding metal melting points, internal cooling is crucial to safeguard the blades and extend their lifespan. This study’s main goal is to apply rib tubular or turbulence promoters in internal cooling turbine blades, with a focus on managing temperature and maximizing HT to enhance GT blade-cooling systems. To achieve this, the proposed method analyzes the effectiveness of ribs by employing internal rib configurations, subsequently coated with composite nanomaterials such as thermal polymer and titanium carbide powder. The study investigates turbulent flow through the square passage at various Reynolds Numbers (Re), maintains constant ambient hot air temperature, and evaluates the performance of ribs. Specifically, the flow and HT within a square channel, resembling the air-cooled turbine blade cross-section, will be examined. The effectiveness of the GOA–SDRN method will then be assessed using MATLAB and compared against existing methodologies. The proposed method outperforms existing optimization methods significantly, achieving the highest efficiency of 94%, compared to 62% for SSA, 70% for CSA, and 84% for HBO. Additionally, the proposed method exhibits the lowest cost of $35, compared to $67 for SSA, $55 for CSA, and $48 for HBO. In summary, the proposed method offers superior efficiency and cost-effectiveness, making it the preferred choice for the application.