Search results for "Structural engineering"
showing 10 items of 1998 documents
Electromechanical impedance method for the health monitoring of bonded joints: Numerical modelling and experimental validation
2014
The electromechanical impedance (EMI) method is one of the many nondestructive evaluation approaches proposed for the health monitoring of aerospace, civil, and mechanical structures. The method consists of attaching or embedding one or more wafer-type piezoelectric transducers (PZTs) to the system of interest, the host structure, and measuring certain electrical characteristics of the transducers. As these characteristics are also related to the impedance of the host structure, they can be used to infer the mechanical properties of the monitored structure. In the study presented in this paper, we utilize the EMI to monitor the quality of adhesively bonded joints. A finite element formulati…
Computation of flow velocity in rough channels
2006
Accurate estimate of flow-velocity profile is of crucial importance both for scientific purposes and for solving numerous engineering problems that include, among others, sediment transport, contaminant transport, flow resistance evaluation. This paper presents a new empirical equation to represent the vertical velocity profile. The proposed equation is essentially a modified form of the well-known logarithm law of the wall and contains three parameters having a clear physical meaning. The applicability of the equation and its accuracy assessment for different hydraulic conditions, including non-uniform conditions, is verified by using experimental data obtained by different sources. The va…
Short-duration rainfalls in Sicily
1990
The Italian Hydrographic Service publishes yearly maximum rainfall depths with 1-, 3-, 6-, 12-, and 24-hr duration, recorded by recording rain gauges. It also publishes selected short-duration (t<1 hr) rainfall amounts. It is impossible to carry out a statistical analysis of the short-duration rainfalls for each recording rain gauge because the published data correspond to different record durations and to different recording rain gauges from year to year. Therefore, there is a practical need to derive empirical relationships between the 1-, 3-, 6-, 12-, and 24-hr duration amounts and shorter duration (t<1 hr) rainfall amounts. Such a relationship has been proposed by Bell and has been veri…
Closed-form solutions of the energy balance equation for drip laterals under the Darcy-Weisbach resistance formula
2018
Many studies have investigated easy methods to design drip laterals, as well as the best resistance equation to use, which is fundamental to accurately account for friction losses. This paper addresses both the features of lateral design relationships and the influence of the friction-loss equation on the design variables. First, simple closed-form solutions of the energy balance equation for both sloped and horizontal drip laterals are derived with the simplified Darcy-Weisbach resistance formula by assuming the Darcy friction factor as invariant versus the Reynolds number. Second, an error analysis is performed assuming the friction factor as constant in the design, which is compared to u…
Future district heating plant integrated with municipal solid waste (MSW) gasification for hydrogen production
2019
Abstract Characterizing municipal solid waste (MSW) is a critical step in planning, designing, operating, or upgrading solid waste management systems. For a theoretical investigation of hydrogen production by gasification and water-gas shift reaction, we characterized Norwegian MSW and used the data. Three different gasification setups, named as ‘A-1’, ‘A&S-2’, and ‘S-3’ were modeled using Aspen plus simulation software for direct and indirect gasification processes according to the different gasification agents. The MSW characterization result showed a reasonable agreement with existing studies in different countries. The maximum hydrogen yield achieved in setup ‘S-3’ was around 94% of the…
Reduced weather data for building climatization and application to 29 European locations
1995
Abstract A method for setting up a reference year of reduced temperature data, proposed by Klein and Erbs, has been applied by us to 29 European locations for which an official test-reference year is available. This reference year of reduced temperatures may be utilized in computer programs for analysis of the thermal behaviour of buildings. The effectiveness of the method has been tested by calculating the annual energy demand in 29 European locations for three modules with different thermophysical characteristics.
Innovative control logics for a rational utilization of electric loads and air-conditioning systems in a residential building
2015
The paper focuses on the evaluation of the impact on residential buildings of innovative control logics defined for a rational utilization of the electric loads and air-conditioning systems. The control logics are implementable thanks to a Decision Support and Energy Management Systems developed by the same authors and easily installable in new and still-existing houses. The paper shows how a significant reduction of the primary energy consumption can be obtained by controlling the air-conditioning units together with the other electric loads of the house. After having explained how the control logics operate, a simulation tool is described, developed for a preliminary evaluation of their e…
Electricity demand response schemes in China: Pilot study and future outlook
2021
Abstract Electricity demand response (DR) improves the overall energy management efficiency and allows for the integration of large-scale renewable energy into the power grid through interactive management and control of the supply and demand sides. However, in China and other emerging countries (e.g., Japan and Australia) with DR programs, the DR market mechanism is not well-established. This is particularly the situation in countries where the state power system is not freely open to participate in the DR market. Previous research has proven that considerable DR resources are largely existing in the demand side; however, the dearth of a market mechanism hinders the development of DR. Henc…
Parametric Hull Design with Rational Bézier Curves and Estimation of Performances
2021
In this paper, a tool able to support the sailing yacht designer during the early stage of the design process has been developed. Cubic Rational Bézier curves have been selected to describe the main curves defining the hull of a sailing yacht. The adopted approach is based upon the definition of a set of parameters, say the length of waterline, the beam of the waterline, canoe body draft and some dimensionless coefficients according to the traditional way of the yacht designer. Some geometrical constraints imposed on the curves (e.g., continuity, endpoint angles, curvature) have been conceived aimed to avoid unreasonable shapes. These curves can be imported into any commercial Computer Aide…
Modelling Aspects in Accumulative Roll Bonding Process by Explicit Finite Element Analysis
2013
Accumulative Roll-Bonding (ARB) process is a severe plastic deformation (SPD) process, capable of developing grains below 1 μm in diameter and improving mechanical properties of the material. In this study, the authors compared two different FE-codes with respect of its applicability for numerical analysis of the ARB process. Modelling this process was achieved using the explicit code for Abaqus/CAE both in 2D and 3D. The proposed model was used to assess the impact of ARB cycles on the final material properties. The numerical results in 2D and 3D were compared and contrasted. The research work presented in this paper is focused on the simulation optimization based on CPU time minimization.…