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The purpose of this paper is to present the status of the on-going development of the new computerized environment for aircraft synthesis and integrated optimization methods (CEASIOM) and to compare results of different aerodynamic tools. The concurrent design of aircraft is an extremely interdisciplinary activity incorporating simultaneous consideration of complex, tightly coupled systems, functions and requirements. The design task is to achieve an optimal integration of all components into an efficient, robust and reliable aircraft with high performance that can be manufactured with low technical and financial risks, and has an affordable life-cycle cost.

CEASIOM (www.ceasiom.com) is a framework that integrates discipline-specific tools like computer-aided design, mesh generation, computational fluid dynamics (CFD), stability and control analysis and structural analysis, all for the purpose of aircraft conceptual design.

A new CEASIOM version is under development within EU Project AGILE (www.agile-project.eu), by adopting the CPACS XML data-format for representation of all design data pertaining to the aircraft under development.

Results obtained from different methods have been compared and analyzed. Some differences have been observed; however, they are mainly due to the different physical modelizations that are used by each of these methods.

This paper summarizes the current status of the development of the new CEASIOM software, in particular for the following modules: CPACS file visualizer and editor CPACSupdater (Matlab) Automatic unstructured (Euler) & hybrid (RANS) mesh generation by sumo Multi-fidelity CFD solvers: Digital Datcom (Empirical), Tornado (VLM), Edge-Euler & SU2-Euler, Edge-RANS & SU2-RANS Data fusion tool: aerodynamic coefficients fusion from variable fidelity CFD tools above to compile complete aero-table for flight analysis and simulation.

A collaborative design environment is needed for multidisciplinary design optimization (MDO) process, based on all the modules those for different design/analysis disciplines, and a systematic coupling should be made to carry out aerodynamic shape optimization (ASO), which is an important part of MDO.

Computerized environment for aircraft synthesis and integrated optimization methods (CEASIOM)-ASO is developed based on loosely coupling all the existing modules of CEASIOM by MATLAB scripts. The optimization problem is broken down into small sub-problems, which is called “sequential design approach”, allowing the engineer in the loop.

CEASIOM-ASO shows excellent design abilities on the test case of designing a blended wing body flying in transonic speed, with around 45 per cent drag reduction and all the constraints fulfilled.

Authors built a complete and systematic technique for aerodynamic wing shape optimization based on the existing computational design framework CEASIOM, from geometry parametrization, meshing to optimization.

CEASIOM-ASO provides an optimization technique with loosely coupled modules in CEASIOM design framework, allowing engineer in the loop to follow the “sequential approach” of the design, which is less “myopic” than sticking to gradient-based optimization for the whole process. Meanwhile, it is easily to be parallelized.

The goal for this paper is to bring the easy‐to‐use geometry drawing software RDS to a “solid” mesh, which could be analyzed and simulated in CEASIOM, to enhance both CEASIOM and RDS's capabilities.

The RDS‐SUMO interface is developed based on the feature that both RDS and SUMO define their geometric model using cross‐sectional information, i.e. their “universe” shapes are close to each other.

The translation is automated and allows the engineer to easily modify and augment the geometry in the process. Two test cases are shown, with their high quality Euler mesh and CFD computations. The A321‐look‐alike test case tests the mesh quality for transonic aerodynamics, such as high‐speed trim and drag divergence; the twin‐prop asymmetric aircraft is a “diffi+cult” non‐conventional configuration analyzed for yaw stability in one‐engine out mode.

This paper shows that the CFD solutions based on solid grids could be obtained once the design is proposed and the RDS wire‐frame model is available. The aerodynamic properties can then be predicted in early design stage, which is very efficient for preliminary aircraft design.

This fast meshing tool could obtain “working” grids of a new design within hours.

This paper aims to determine how the viscosity and curing agent content affect the flowability of moist silica sand granules. In addition, a coating device was designed according to the flow properties of silica sand granules.

The flowability of silica sand granules premixed with two curing agents of different viscosities is studied using a Jenike shear apparatus. An open-ended device was used in discharge testing of sand granules with a design based on the variable dip angle of the two plates and variable outlet size.

The test results show that increasing the curing agent content would significantly decrease the flowability of silica sand granules, and a curing agent of higher viscosity has a greater effect on the flowability of silica sand. The presence of a curing agent strengthens the cohesion among sand granules, lubricates them and restrains their deformation. The shape function of the coating device was obtained by theoretical derivation.

The flow properties provide a valuable theoretical guidance for the design of coating device for sand mold printing.

This paper deals with experimental work on flow properties of silica sand granules with different viscosities and curing agent content. The shape function of a wedge-shaped coating device is obtained based on experimental data.

The purpose of this paper is to present a semi-analytical solution to one-dimensional (1D) consolidation induced by a constant inner point sink in viscoelastic saturated soils.

Based on the Kelvin–Voigt constitutive law and 1D consolidation equation of saturated soils subject to an inner sink, the analytical solutions of the effective stress, the pore pressure and the surface settlement in Laplace domain were derived by using Laplace transform. Then, the semi-analytical solutions of the pore pressure and the surface settlement in physical domain were obtained by implementing Laplace numerical inversion via Crump method.

As for the case of linear elasticity, it is shown that the simplified form of the presented solution in this study is the same as the available analytical solution in the literature. This to some degree depicts that the proposed solution in this paper is reliable. Finally, parameter studies were conducted to investigate the effects of the relevant parameters on the consolidation settlement of saturated soils. The presented solution and method are of great benefit to provide deep insights into the 1D consolidation behavior of viscoelastic saturated soils.

The presented solution and method are of great benefit to provide deep insights into the 1D consolidation behavior of viscoelastic saturated soils. Consolidation behavior of viscoelastic saturated soils could be reasonably predicted by using the proposed solution with considering variations of both flux and depth because of inner point sink.

The paper aims to quantitatively investigate vacant industrial land valuation accuracy in China, given the importance of the industrial market as an underlying pillar to promote urban growth especially in emerging economies.

In China, the government formulates a Land Benchmark Price (LBP) to serve as a price reference point to sell land rights. To gain an in-depth understanding of the valuation practice by LBP, this paper uses correlation analysis to investigate the varying dynamics between the transaction-based prices and LBP appraisal-based estimates. Furthermore, a margin of error examination investigates the distortion in LBP land appraisals, with an amended LBP presented to improve the accuracy of the current LBP method.

Different influencing factors are identified to impact the actual market transaction prices and the LBP construction, leading to a large discrepancy in industrial land appraisals. A systematic problem is recognised that the construction of the LBP follows urban bid curve theory, whereas the land transaction prices do not, demonstrating that an urgent LBP update is needed to capture the market dynamics for industrial market.

The paper sets out discrepancies in valuation accuracy surrounding the application of the LBP valuation approach in China. This has practical implications for valuers in terms of raising their awareness of the deficiencies in the approach and the pitfalls they need to guard against in their appraisals. It also has implications for developers and investors who rely on valuer appraisals to assess the viability of land purchases; hence, they need to express caution in the appraisal advice sought. Finally, the results demonstrate to the standard setters how they need to modify the LBP equations to better capture market dynamics.

The paper examines valuation accuracy in transitional economies, through valuation differentials between appraised price and the transacted price. The value of the work lies in the analysis of the fundamental differentials between market price and appraised value, which is of importance to investors/developers, practicing valuers, as well as government officials responsible for setting the valuation standards.

The purpose of this paper is to explore the effects of wind direction and ease allowance on thermal comfort in sportswear.

The effects of wind direction (front, side, back and calm (no wind) 1.5 m/s) and seven magnitudes of ease allowance on sportswear thermal insulation and surface temperature were investigated. An 11 zones’ thermal manikin was used to acquire the static thermal insulation. Surface temperature was captured by a thermal imager.

The results showed that the wind was a significant effect on thermal performance, however, wind direction effect was only significant in the segment covered with multilayer fabric, such as the abdomen and hip (p=0.034). Although the ease allowance influenced the overall thermal insulation obviously, the difference between seven sizes suits was not significant. Nevertheless, the ease allowance affected the surface temperature of chest and back significantly (p=0.023, 0.007). Correlation between thermal insulation and surface temperature was negative, and correlation level was degraded when affected by wind factor.

Sportswear’s fabric and style did not discussed as effect factors. It would be taken into accounted in the future research.

Wind direction impact thermal comfort in multilayer regions significantly. It is a reference to improve sportswear’s comfort design.

In this paper, the effects of the adhesive and curing agent contents on the tensile strength, bending strength, gas evolution and gas permeability of three-dimensional printed sand molds are studied. A strength model of the three-dimensional printed sand molds is proposed. The multi-material composite sand mold forming test is carried out. In addition, the mesostructure of the sand mold is studied.

The performances of three-dimensional printed sand mold such as tensile strength, bending strength, gas evolution and gas permeability are studied using the standard test methods. The mesostructure of the sand mold is studied by digital core technology.

A sand mold strength model based on the resin adhesive content, curing agent content and sand mold compactness are obtained. Two types of multi-material composite three-dimensional printed sand molds are proposed. An increase in the curing agent content in the sand mold widens the mesoscopic characteristic size distribution of the sand mold, and large-sized mesostructures appear, resulting in a decrease in the sand mold bearing capacity.

Process parameters that affect the performance of three-dimensional printed sand mold are revealed. The sand mold bearing curve provides a reference for the ultimate design of three-dimensional printed sand mold.

The paper deals with experimental work on the performance and mesostructure of multi-material composite three-dimensional printed sand mold with different contents of adhesive and curing agent. That gives a perspective on future designs of sand mold based on these principles.