Home / Advanced Search

  • Title/Keywords

  • Author/Affliations

  • Journal

  • Article Type

  • Start Year

  • End Year

Update SearchingClear
  • Articles
  • Online
Search Results (1,031)
  • Open Access

    ARTICLE

    ENERGY EFFECTIVENESS OF SIMULTANEOUS HEAT AND MASS EXCHANGE DEVICES

    G. Prakash Narayana, Karan H. Mistrya, Mostafa H. Sharqawya, Syed M. Zubairb, John H. Lienhard Va,†

    Frontiers in Heat and Mass Transfer, Vol.1, No.2, pp. 1-13, 2010, DOI:10.5098/hmt.v1.2.3001

    Abstract Simultaneous heat and mass exchange devices such as cooling towers, humidifiers and dehumidifiers are widely used in the power generation, desalination, air conditioning, and refrigeration industries. For design and rating of these components it is useful to define their performance by an effectiveness. In this paper, several different effectiveness definitions that have been used in literature are critically reviewed and an energy based effectiveness which can be applied to all types of heat and mass exchangers is defined. The validity and the limitations of the various effectiveness definitions are demonstrated by way of several examples More >

  • Open Access

    ARTICLE

    Fracture Behavior in AFM-Specimen with Single Crack under Different Loading Conditions

    Qing-fen Li1, Li Zhu1, Shi-fan Zhu1, F-G Buchholz1

    Structural Durability & Health Monitoring, Vol.6, No.3&4, pp. 273-288, 2010, DOI:10.3970/sdhm.2010.006.273

    Abstract The fracture behavior in all fracture mode (AFM)-specimen with a single edged crack under different loading conditions is investigated by the aid of the commercial ANSYS code. The separated strain energy release rates (SERRs) along the crack front are calculated by the modified virtual crack closure integral (MVCCI)-method. It is shown that the computational results of the AFM-specimen are in good agreement with some available findings for pure mode I, mode II, mode III, and mixed-mode I+III loading conditions. Furthermore, the crack growth problems under complex mixed-mode II+III loading condition by using the AFM-specimen, are More >

  • Open Access

    ARTICLE

    Energetic Galerkin BEM for wave propagationNeumann exterior problems

    A. Aimi1, M. Diligenti1, S. Panizzi1

    CMES-Computer Modeling in Engineering & Sciences, Vol.58, No.2, pp. 185-220, 2010, DOI:10.3970/cmes.2010.058.185

    Abstract In this paper we consider 2D wave propagation Neumann exterior problems reformulated in terms of a hypersingular boundary integral equation with retarded potential. Starting from a natural energy identity satisfied by the solution of the differential problem, the related integral equation is set in a suitable space-time weak form. Then, a theoretical analysis of the introduced formulation is proposed, pointing out the novelties with respect to existing literature results. At last, various numerical simulations will be presented and discussed, showing accuracy and stability of the space-time Galerkin boundary element method applied to the energetic weak More >

  • Open Access

    ABSTRACT

    The energy localization by the rupture propagation

    I.A. Miklashevich1

    The International Conference on Computational & Experimental Engineering and Sciences, Vol.15, No.4, pp. 145-152, 2010, DOI:10.3970/icces.2010.015.145

    Abstract The simple analytical model for the energy flux by the earthquake is proposed. The energy flux can be evaluated through the Umov-Pointing vector by the rupture propagation in media. Discontinuity of vector components is found. This discontinuity cause the change of an energy flow direction and localization of the energy field. More >

  • Open Access

    ABSTRACT

    Fracture behavior of plain concrete beams -- experimental verification of one parameter model

    B.K.Raghu Prasad1, Rabindra Kumar Saha1, A.R.Gopalakrishnan1

    The International Conference on Computational & Experimental Engineering and Sciences, Vol.14, No.3, pp. 65-84, 2010, DOI:10.3970/icces.2010.014.065

    Abstract Several different models have been proposed to characterize mode-I crack propagation in concrete. The fictitious crack model proposed by Hillerborg et al. and the blunt crack band theory developed by Bazant & Oh are particularly well suited for a finite element analysis. The two-parameter fracture model proposed by Jenq & Shah is found to be applicable only for beams with s/w=4, where s=span & w=depth of the beam. The general applicability of the model for other testing configurations is not published. In the present study an experimental verification of a one-parameter model based on fundamental… More >

  • Open Access

    ARTICLE

    Application of Energy Finite Element Method to High-frequency Structural-acoustic Coupling of an Aircraft Cabin with Truncated Conical Shape

    M. X. Xie1, H. L. Chen1, J. H. Wu1, F. G. Sun1

    CMES-Computer Modeling in Engineering & Sciences, Vol.61, No.1, pp. 1-22, 2010, DOI:10.3970/cmes.2010.061.001

    Abstract Energy finite element method (EFEM) is a new method to solve high-frequency structural-acoustic coupling problems, but its use has been limited to solving simple structures such as rods, beams, plates and combined structures. In this paper, the high-frequency structural-acoustic coupling characteristics of an aircraft cabin are simulated by regarding the shell as a number of flat shell elements connected with a certain angle in EFEM. Two tests validated the method employed in this paper. First, the structural response analysis of a cylinder was calculated in two ways: dividing the shell by axis-symmetric shells after deriving… More >

  • Open Access

    ARTICLE

    A Comparative Study of Phase Changing Characteristics of Granular Phase Change Materials Using DSC and T-History Methods

    Mohamed Rady1, Eric Arquis2

    FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.2, pp. 137-152, 2010, DOI:10.3970/fdmp.2010.006.137

    Abstract In the present article, differential scanning calorimetry (DSC) and a modified T-history method have been used to study the phase changing behavior of granular composites. Further modifications and improvements of the two methods are employed to handle granular materials undergoing phase change over a temperature range. A simple procedure has been advised to obtain accurate results from the DSC measurements based on the estimation of the thermal resistance between the sample and its enclosure. The concept of enthalpy and its relationship with temperature has been employed in the T-history analysis to obtain enthalpy-temperature and apparent More >

  • Open Access

    ARTICLE

    Dynamic Properties of Cortical Bone Tissue: Izod Tests and Numerical Study

    Adel A. Abdel-Wahab1, Angelo Maligno1, Vadim V. Silberschmidt1

    CMC-Computers, Materials & Continua, Vol.19, No.3, pp. 217-238, 2010, DOI:10.3970/cmc.2010.019.217

    Abstract Bone is the principal structural component of a skeleton: it assists the load-bearing framework of a living body. Structural integrity of this component is important; understanding of its mechanical behaviour up to failure is necessary for prevention and diagnostic of trauma. In dynamic events such as traumatic falls, involvement in car crash and sports injuries, bone can be exposed to loads exceeding its structural strength and/or fracture toughness. By developing adequate numerical models to predict and describe its deformation and fracture behaviour up to fracture, a detailed study of reasons for, and ways to prevent… More >

  • Open Access

    ARTICLE

    Invariant Based Transversely-Isotropic Material and Failure Model for Fiber-Reinforced Polymers

    M. Vogler1, G. Ernst1, R. Rolfes1

    CMC-Computers, Materials & Continua, Vol.16, No.1, pp. 25-50, 2010, DOI:10.3970/cmc.2010.016.025

    Abstract In this article, a constitutive formulation of a transversely-isotropic material and failure model for fiber-reinforced polymers is presented comprising pre-failure material nonlinearities, a novel invariant based quadratic failure criterion (IQC) as well as post failure material softening. The failure surface of the IQ criterion is assumed to take the influence of triaxiality on fracture into account. Further, a distinction between fiber failure and inter-fiber failure is conducted. Material softening is governed by a fracture energy formulation and the introduction of an internal length. The constitutive model is implemented into a programming user interface of the More >

  • Open Access

    ARTICLE

    Studies on Methodological Developments in Structural Damage Identification

    V. Srinivas1, Saptarshi Sasmal1, K. Ramanjaneyulu2

    Structural Durability & Health Monitoring, Vol.5, No.2, pp. 133-160, 2009, DOI:10.3970/sdhm.2009.005.133

    Abstract Many advances have taken place in the area of structural damage detection and localization using several approaches. Availability of cost-effective computing memory and speed, improvement in sensor technology including remotely monitored sensors, advancements in the finite element method, adaptation of modal testing and development of non-linear system identification methods bring out immense technical advancements that have contributed to the advancement of modal-based damage detection methods. Advances in modal-based damage detection methods over the last 20-30 years have produced new techniques for examining vibration data for identification of structural damage. In this paper, studies carried out… More >

Displaying 991-1000 on page 100 of 1031. Per Page