This article is closely tied to the author’s Radial-axial runner blade design using the coordinate slice technique. It picks up the thread of the content and follows as stated in the Future development section with conformal mapping of camber curves. The article introduces Proposition for theoretically pure conformity and the computational procedure of the mapping feasible and useful in engineering practice. The feasibility bears an error and leads to a quasi-conformity which is evaluated. Contribution of this study consists in the quasi-conformal construction with error control. The geometric object for the construction is the 3D Euclidean space with a curvilinear coordinate system. It is considered a differentiable manifold, and maps between such spaces are tools. The blade camber surface is described by curves conformally mapped into coordinate slices. The geometric entities and maps can be viewed as objects and methods of a computer object-oriented program. Francis runner blade serves as an example. The potential of the method lies in design freedom based on stacking the blade including stacked X-Blade design. This is presented in an example.
Investigating the observability of a comprehensive system prior to designing an observer is crucial for determining the accuracy and reliability of the observation model. This model is essential for solving problems related to identification, navigation, and control, particularly in inertial navigation system (INS) where sensor quantity is limited while the control signals need to be optimized. In this paper, we analyzes the degree of observerbility of states in INS, including position, velocity, attitude, and sensor biases, by utilizing a Lie derivative approach. The proposed approach leverages the advantages of the Lie derivative to evaluate the observability level of states under different conditions involving system dynamic, observer selection, and computational methods. Simulation results indicate that the degree of observability varies across different scenarios.
The present analysis explores the mass and heat transport behavior of bioconvective Boger ternary nanofluid flow via a shrinking/elongating deforming cone with a magnetic field and porous medium. Moreover, the significance of nonlinear thermal radiation, activation energy, heat sink/source, and convective boundary conditions on the fluid flow is considered to assess the mass and heat transfer attributes. The present analysis is pertinent to systems that need improved thermal management, especially in applications like cooling technologies and energy devices that include complicated fluids and spinning equipment. In contrast to traditional research, the current study concurrently takes into account nonlinear thermal radiation, convective boundary conditions, and heat sink/source, all of which have a substantial impact on thermal transport but are frequently handled independently. Similarity transformations are employed to convert the governing partial differential equations (PDEs) into ordinary differential equations (ODEs). The finite difference method (FDM) is utilized to solve the reduced ODEs numerically. The study optimizes the heat transfer rate impacted by significant factors using the response surface methodology (RSM). The central composite design is employed in a variety of industrial applications to statistically analyze and optimize the heat transfer rate. A graphic depicts how different circumstances affect the different profiles. An increase in the solvent percentage is indicative of improved velocity profiles. As radiation and heat sink/source parameters amplify, the thermal profile also rise. An upsurge in the Biot number enhances the temperature profile. As the solvent fraction parameter advances, the skin friction diminishes by about 1.96 % and 3.31 %, indicating a reduction in wall shear attributable to increased elasticity.
Mycelium-stabilized straw insulation (MSSI) is a biodegradable, bio-based material considered a sustainable alternative to conventional thermal insulation products; however, reliable experimental data describing its thermal performance under temperature conditions relevant to building operation remain limited. The aim of this study was to determine the thermal conductivity of MSSI produced from wheat straw inoculated with Pleurotus ostreatus and to evaluate the influence of temperature on its thermal behaviour. Thermal conductivity measurements were performed using a FOX314 heat flow meter apparatus in accordance with ISO 8301. Six samples with bulk densities ranging from approximately 81 to 93 kg/m3 were tested at a mean temperature of 10 °C, while additional measurements on three representative samples were conducted over a temperature range from −10 °C to +20 °C. All specimens were subjected to long-term conditioning prior to testing to ensure mass stability. The measured thermal conductivity values ranged from 0.0378 W/(m·K) at −10 °C to 0.0425 W/(m·K) at +20 °C, with a mean value of 0.0416 W/(m·K) at 10 °C. The results demonstrate a clear increase in thermal conductivity with rising temperature, following an approximately linear trend. This study provides temperature-dependent thermal conductivity data for stabilized mycelium-straw insulation measured under steady-state conditions, addressing a gap in existing research. The obtained results reflect material behaviour under realistic building operating temperatures and support the potential application of MSSI as an environmentally sustainable thermal insulation material.
This paper presents a device sensitive to dielectric material properties, based on a square shaped split-ring resonator (SRR) metasurface operating in the terahertz (THz) frequency band. In the proposed structure, most of the single resonant element is anchored in a silicon substrate, while the remaining part is movable (a magnetic-material-based free-standing cantilever) and can be deformed by an external magnetic field. Owing to its variable geometry, these micro-electro-mechanical systems (MEMS) constitute a reconfigurable resonant element. The structure is designed and analyzed using finite element method (FEM) numerical modeling. The analytical model is presented using an equivalent electrical circuit model. The resonance behavior (at 0.38 THz and 1.13 THz under zero-deflection conditions) is investigated for dispersive, non-dispersive gaseous and liquid material sweep, and a parametric analysis is performed for various deflection levels. This model-based analysis shows that frequency shift of the tunable metasurface sensor, under external material influence and different deflection levels, has potential for sensing (based on detecting changes in the effective permittivity (ε eff)) and non-destructive testing applications. This analysis makes the path for future fabrication and experimental validation.
