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2003

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Full-Text Articles in Engineering

Влияние На Окружающую Среду Технологии Непрерывного Литья, Marian Mazur, Marek Bogacki, Robert Oleniacz, Agnieszka Łopata Dec 2003

Влияние На Окружающую Среду Технологии Непрерывного Литья, Marian Mazur, Marek Bogacki, Robert Oleniacz, Agnieszka Łopata

Robert Oleniacz

This article presents a complex analysis of the impact of the technology of continuous casting of steel (CCS) on the rate of the air pollutant emissions from one of the Polish steel and iron plants. The emission sources occurring in the production process have been identified and their rate has been determined. The implementation of CCS has brought about significant changes in the production cycle of the steel plant and it also has caused an increase of the production effectiveness of steel products. The calculated environment effects have shown a considerable emission decrease of all pollutants in the scale of …


Prediction Of Dopant Ionization Energies In Silicon: The Importance Of Strain, A. Rockett, Duane D. Johnson, S. V. Khare, B. R. Tuttle Dec 2003

Prediction Of Dopant Ionization Energies In Silicon: The Importance Of Strain, A. Rockett, Duane D. Johnson, S. V. Khare, B. R. Tuttle

Duane D. Johnson

Based on a hydrogenic state and strain changes upon defect charging, we propose a simple, parameter-free model that agrees well with the observed group III and V monovalent-impurity ionization energies in Si, revealing the importance of such strain effects. Changes in lattice strain upon defect charging are obtained via superposition and elasticity theory using atomic relaxations from density functional theory.


Facilitating Conversations Among Web Services As Speech-Act Based Discourses, Karthikeyan Umapathy, Sandeep Purao, Vijayan Sugumaran Dec 2003

Facilitating Conversations Among Web Services As Speech-Act Based Discourses, Karthikeyan Umapathy, Sandeep Purao, Vijayan Sugumaran

Karthikeyan Umapathy

Web services composition is an emerging paradigm for enabling application deployment and integration within and across organizational boundaries. A landscape of languages and techniques for web services composition has emerged and is continuously being enriched. The ability to support conversations taking place between Web Services is an important area that is not yet fully addressed by the emerging standards. We suggest an approach to derive speech-act based message structures for conversation support that can complement existing standards.


Microstructure And Interface Characteristics Of B4c, Sic And Al2o3 Reinforced Al Matrix Composites: A Comparative Study Dec 2003

Microstructure And Interface Characteristics Of B4c, Sic And Al2o3 Reinforced Al Matrix Composites: A Comparative Study

A.S. Md Abdul Haseeb

Three aluminium metal matrix composites containing reinforcing particles of B4C, SiC and Al2O3 (0-20vol.%) were processed. The stir-casting manufacturing route followed by hot extrusion was utilized, being one of the cost-effective industrial methods. A clear interfacial reaction product/layer was found at Al-SiC interface for composites held for a relatively long processing time (>30 min). No reaction product was observed at Al-B4C and Al-Al2O3 interfaces at the resolution limit of the SEM used. On the other hand, two secondary phases (alumina and another phase containing aluminium, boron and carbon) were found in the aluminum matrix away from the interface in …


Microstructure And Interface Characteristics Of B4c, Sic And Al2o3 Reinforced Al Matrix Composites: A Comparative Study Dec 2003

Microstructure And Interface Characteristics Of B4c, Sic And Al2o3 Reinforced Al Matrix Composites: A Comparative Study

A.S. Md Abdul Haseeb

Three aluminium metal matrix composites containing reinforcing particles of B4C, SiC and Al2O3 (0-20vol.%) were processed. The stir-casting manufacturing route followed by hot extrusion was utilized, being one of the cost-effective industrial methods. A clear interfacial reaction product/layer was found at Al-SiC interface for composites held for a relatively long processing time (>30 min). No reaction product was observed at Al-B4C and Al-Al2O3 interfaces at the resolution limit of the SEM used. On the other hand, two secondary phases (alumina and another phase containing aluminium, boron and carbon) were found in the aluminum matrix away from the interface in …


Ann-Based Technique For Predicting Voltage Collapse In Power Systems, Almoataz Youssef Abdelaziz Dec 2003

Ann-Based Technique For Predicting Voltage Collapse In Power Systems, Almoataz Youssef Abdelaziz

Almoataz Youssef Abdelaziz

Voltage stability problems have been one of the major concerns for electric utilities as a result of heavy loading of power system. This paper reports on an investigation on the application of Artificial Neural Networks (ANN) in voltage stability assessment using the energy function technique. A multi-layer feed-forward ANN with error back-propagation learning algorithm is proposed for calculation of Voltage Stability Margins (VSM). Extensive testing of the proposed ANN based approach indicates its validity for determination of power system voltage collapse. Simulation results on two test systems are reported in the paper.


Structural Usable Speech Measure Using Lpc Residual, Ananth N. Iyer, Melinda Gleiter, Brett Y. Smolenski, Robert E. Yantorno Dec 2003

Structural Usable Speech Measure Using Lpc Residual, Ananth N. Iyer, Melinda Gleiter, Brett Y. Smolenski, Robert E. Yantorno

Ananth N Iyer

In an operational environment speech is degraded by many kinds of interferences. The operation of many speech processing techniques are plagued by such interferences. Usable speech extraction is a novel concept of processing degraded speech data. The idea of usable speech is to identify and extract portions of degraded speech that are considered useful for various speech processing systems. The performance reduction of speaker identification systems under degraded conditions and use of usable speech concept to improve the performance has been demonstrated in previous work. A new usable speech measure, based on the structure of Linear Predictive Coding (LPC) residual …


Microstructure And Interface Characteristics Of B4c, Sic And Al2o3 Reinforced Al Matrix Composites: A Comparative Study, Haseeb Asma Dec 2003

Microstructure And Interface Characteristics Of B4c, Sic And Al2o3 Reinforced Al Matrix Composites: A Comparative Study, Haseeb Asma

Haseeb ASMA

Three aluminium metal matrix composites containing reinforcing particles of B4C, SiC and Al2O3 (0-20 vol.%) were processed. The stir-casting manufacturing route followed by hot extrusion was utilized, being one of the cost-effective industrial methods. A clear interfacial reaction product/layer was found at Al-SiC interface for composites held for a relatively long processing time (>30 min). No reaction product was observed at Al-B4C and Al-Al2O3 interfaces at the resolution limit of the SEM used. On the other hand, two secondary phases (alumina and another phase containing aluminium, boron and carbon) were found in the aluminum matrix away from the interface …


Non-Steady-State Approach #11;To Steady-State Kinetics: #11;Case Study Of H2s Oxidation By Oxygen, Andrey N. Zagoruiko, Vladimir V. Mokrinskii Nov 2003

Non-Steady-State Approach #11;To Steady-State Kinetics: #11;Case Study Of H2s Oxidation By Oxygen, Andrey N. Zagoruiko, Vladimir V. Mokrinskii

Andrey N Zagoruiko

Non-steady-state kinetic models may be used for treatment of steady-state kinetic data in case when algebraic elaboration of steady-state kinetic equations is impossible or complicated. The proposed approach includes numerical integration of time-dependent differential equations until achievement of steady-state, resulting in possibility to numerically obtain the rate values for separate reaction stages for given composition of reaction mixture. The obtained non-steady-state model may be then applied in simulation of catalyst pellets and catalyst beds in research and engineering purposes. The case study demonstrates application of such approach for steady-state kinetic description of complicated reaction system of H2S oxidation by oxygen. …


Memories Of Dad 15.11.1902- 16.10.1970 A Celebration Of The Life And Works Of Edmund Ramsay Wigan, Marcus R. Wigan Nov 2003

Memories Of Dad 15.11.1902- 16.10.1970 A Celebration Of The Life And Works Of Edmund Ramsay Wigan, Marcus R. Wigan

Marcus R Wigan

Edmund Ramsay Wigan was a distinguished Acoustical and Mechanical Engineer, who patented literally several dozen devices and ideas, was responsible for the field radios used by the Allied forces in Europe in World War 2, and when invited as the special merit Senior Principal at the BBC Research lab in Kingston, Surrey, invented the quality meters, tuned all the BBC broadcasting aerials for quality, and did applied research creating a reliable measure for subjective levels of sound distortion. As a minor practical measure invented the one cycle offset used ever since to avoid feedback in large multi-miked rooms. He was …


Usable Speech Detection Using Linear Predictive Analysis, Nitya Sundaram, Robert E. Yantorno, Brett Y. Smolenski, Ananth N. Iyer Nov 2003

Usable Speech Detection Using Linear Predictive Analysis, Nitya Sundaram, Robert E. Yantorno, Brett Y. Smolenski, Ananth N. Iyer

Ananth N Iyer

A speech segment is defined as “usable,” if speech, which is corrupted by interfering speech, can still be used for applications like speaker identification. In tactical communications, where there are multiple signals transmitted over the same channel such as telephone or radio transmission, separation of usable speech from speech corrupted by voices of other speakers is desired. This separation is important in making automatic speaker and speech recognition systems more robust. A novel approach towards developing a usable speech measure could be model-based. Using this concept of model-based usable speech detection, the use of Linear Prediction is investigated. The method …


Convergence Of The Singular Value Based Model Order Reduction Algorithm, Tammy Stitz Nov 2003

Convergence Of The Singular Value Based Model Order Reduction Algorithm, Tammy Stitz

Tammy Stitz

This thesis revisits the singular value based model order reduction technique that was developed in [33] to prove that the solution of the full order model converges to the solution of the reduced order model and to characterize the error between the full order model and the reduced order model.

To prove convergence, a general, stable, linear, time-invariant system is transformed using the technique of [33]. Then, a reduced order model is obtained using the method of matched asymptotics. This reduced order model is the same as that which results
from applying the method of [33] to the original system. …


Light-Induced Defect States In Hydrogenated Amorphous Silicon Centered Around 1.0 And 1.2 Ev From The Conduction Band Edge, Joshua M. Pearce, J. Deng, R. W. Collins, C. R. Wronski Nov 2003

Light-Induced Defect States In Hydrogenated Amorphous Silicon Centered Around 1.0 And 1.2 Ev From The Conduction Band Edge, Joshua M. Pearce, J. Deng, R. W. Collins, C. R. Wronski

Joshua M. Pearce

To take into account the presence of multiple light-induced defect states in hydrogenated amorphous silicon(a-Si:H) the evolution of the entire spectra of photoconductive subgap absorption, α(hν), has been analyzed. Using this approach two distinctly different light-induced defect states centered around 1.0 and 1.2 eV from the conduction band edge are clearly identified. Results are presented on their evolution and respective effects on carrier recombination that clearly point to the importance of these states in evaluating the stability of different a-Si:Hsolar cell materials, as well as elucidating the origin of the Staebler–Wronski effect.


Fast Voltage Contingency Screening Using Radial Basis Function Neural Network, T Jain, L Srivastava, Sn Singh Nov 2003

Fast Voltage Contingency Screening Using Radial Basis Function Neural Network, T Jain, L Srivastava, Sn Singh

SN Singh PhD

No abstract provided.


Analysis Of Core Buckling Defects In Sheet Metal Coil Processing, P.M. Lin, Jonathan A. Wickert Nov 2003

Analysis Of Core Buckling Defects In Sheet Metal Coil Processing, P.M. Lin, Jonathan A. Wickert

Jonathan A. Wickert

The elastic stability of a wound coil comprising a central core and many layers of sheet metal is modeled and analyzed. A common failure mode resulting from unfavorable internal stresses—called v-buckling—is characterized by a section of the core buckling inward, possibly with several nearby sheet metal layers. In the present study, the core is modeled as a thin cylinder that is subjected to (i) the uniform external pressure generated by the coil's wound-in stresses and (ii) a nonuniform elastic foundation around its circumference that represents core-coil contact or loss thereof. The model and an iterative numerical technique are used to …


Study Of Organic Droplets On Metal Surfaces In Aqueous Surfactant Solutions In The Presence Of An Applied Electric Potential, Samuel Morton, R. Counce, D. Keffer, D. Depaoli, M. Hu Oct 2003

Study Of Organic Droplets On Metal Surfaces In Aqueous Surfactant Solutions In The Presence Of An Applied Electric Potential, Samuel Morton, R. Counce, D. Keffer, D. Depaoli, M. Hu

Samuel A Morton

No abstract provided.


Combined Beamforming And Space-Time Block Coding With A Sparse Array Antenna, Robert H. Morelos-Zaragoza, Mohammad Ghavami Oct 2003

Combined Beamforming And Space-Time Block Coding With A Sparse Array Antenna, Robert H. Morelos-Zaragoza, Mohammad Ghavami

Robert Henry Morelos-Zaragoza

In this paper, we continue our investigation of joint beamforming and transmit diversity with space-time block coding. In particular, the performance of a four-element array antenna is considered, in the context of an indoor wireless communication system. The main contribution is to show that transmit diversity may be practically achieved, even with correlated beams produced by a sparse array antenna.


Estimations Of Ammonia And Hydrogen Sulfide Fluxes From Cattle Feedlot Surfaces In Texas High Plains, Bok-Haeng Baek, Jacek A. Koziel, Jarett P. Spinhirne, David B. Parker, Nolan A. Cole Oct 2003

Estimations Of Ammonia And Hydrogen Sulfide Fluxes From Cattle Feedlot Surfaces In Texas High Plains, Bok-Haeng Baek, Jacek A. Koziel, Jarett P. Spinhirne, David B. Parker, Nolan A. Cole

Jacek A. Koziel

A dynamic flow-through chamber system and continuous analyzers were used for on-site measurements of ammonia-nitrogen (NH 3 -N) and hydrogen sulfide-sulfur (H 2 S-S) fluxes from commercial feedlot surfaces in northwestern Texas during two week period in the summer of 2002. Ambient air and air inside chamber temperatures, and manure pack temperature were measured continuously. Manure pack moisture content, pH, and TKN were measured daily to characterize its correlation with NH 3 -N fluxes. The preliminary average NH 3 -N flux from the feedlot surface for the entire measurement period was 1,669 ± 1,212 NH 3 -N µ g/m 2 …


Generation And Calibration Of Standard Gas Mixtures For Volatile Fatty Acids Using Permeation Tubes And Solid Phase Microextraction, Jacek A. Koziel, Jarett P. Spinhirne Oct 2003

Generation And Calibration Of Standard Gas Mixtures For Volatile Fatty Acids Using Permeation Tubes And Solid Phase Microextraction, Jacek A. Koziel, Jarett P. Spinhirne

Jacek A. Koziel

Volatile fatty acids (VFAs) are major components of odors associated with agricultural operations and livestock housing, solid waste processing and disposal, and industrial and municipal wastewater collection and treatment systems. Emissions estimation and assessment of odor control methods depend on reliable air sampling and analysis methods for VFAs. The objective of this research was to develop and test a method for continuous and reliable generation of standard gas mixtures for VFAs based on permeation tubes. Standard gas mixtures for acetic, propionic, isobutyric, butyric, isovaleric, valeric, and hexanoic acids were generated with permeation tubes and monitored for a 100-day period. The …


Zmiany W Metodyce Modelowania Rozprzestrzeniania Się Zanieczyszczeń W Powietrzu Opartej Na Modelu Gaussa, Robert Oleniacz, Marek Bogacki Oct 2003

Zmiany W Metodyce Modelowania Rozprzestrzeniania Się Zanieczyszczeń W Powietrzu Opartej Na Modelu Gaussa, Robert Oleniacz, Marek Bogacki

Robert Oleniacz

The paper presents the changes that have occurred in December 2002 in the Polish reference modeling methodology (based on the stationary Gaussian atmospheric dispersion model) used for the air quality impact assessment in Poland since the 60s of the 20th century. Discusses the changes that have occurred in the preparation of data for the simulation, the procedure used in shortened and full range of calculation, the algorithms of initial computations and the results of calculations.

English Title: Changes in the methodology of modeling the pollutant dispersion in the air based on the Gaussian model.


Neuro-Fuzzy Approach For Development Of New Neuron Model, Manmohan, D. K. Chaturvedi, P. S. Satsangi, P. K. Kalra Oct 2003

Neuro-Fuzzy Approach For Development Of New Neuron Model, Manmohan, D. K. Chaturvedi, P. S. Satsangi, P. K. Kalra

D. K. Chaturvedi Dr.

The training time of ANN depends on size of ANN (i.e. number of hidden layers and number of neurons in each layer), size of training data, their normalization range and type of mapping of training patterns (like X–Y, X–DY, DX–Y and DX–DY), error functions and learning algorithms. The efforts have been done in past to reduce training time of ANN by selection of an optimal network and modification in learning algorithms. In this paper, an attempt has been made to develop a new neuron model using neuro-fuzzy approach to overcome the problems of ANN incorporating the features of fuzzy systems …


Ammonia Concentrations In Poultry Broiler Production Units Treated With Liquid Alum, K. A. Armstrong, Robert T. Burns, F. R. Walker, L. R. Wilhelm, D. Raj Raman Oct 2003

Ammonia Concentrations In Poultry Broiler Production Units Treated With Liquid Alum, K. A. Armstrong, Robert T. Burns, F. R. Walker, L. R. Wilhelm, D. Raj Raman

D. Raj Raman

High ammonia concentrations in commercial broiler production houses can result in poor bird performance, lower feed conversion ratios, and higher mortalities. Growers have traditionally controlled in-house ammonia levels by increasing ventilation. During cold weather, increased ventilation rates result in higher heating energy requirements. Granular alum (aluminum sulfate, Al2(SO4)3 · 14H2O) has been successfully used as a litter amendment to reduce ammonia volatilization from litter inside broiler production houses. In this study, liquid aluminum sulfate was investigated as a litter amendment for ammonia suppression in four commercial poultry-broiler units. This project investigates four treatment levels of liquid alum in four adjacent …


Combined Beamforming And Space-Time Block Coding With Sparse Array Antennas, Robert H. Morelos-Zaragoza Oct 2003

Combined Beamforming And Space-Time Block Coding With Sparse Array Antennas, Robert H. Morelos-Zaragoza

Robert Henry Morelos-Zaragoza

In this paper, the combination of beamforming and space-time block coding is investigated. An adaptive scheme for the assignment of transmission beams is proposed. Data for the determination of beams are obtained using a triangular switch-beam array antenna at the transmitter. The number of peak points is determined from the data and a prescribed threshold level. Orthogonal space-time block coding is then applied to the transmission beams. We examine the distribution of the number of assigned beams as a function of indoor wireless channel parameters. Also, the effects of a small number of array elements and associated correlated beams, and …


Stabilized Blue Emission From Polyfluorene-Based Light-Emitting Diodes: Elimination Of Fluorenone Defects, Xiong Gong Sep 2003

Stabilized Blue Emission From Polyfluorene-Based Light-Emitting Diodes: Elimination Of Fluorenone Defects, Xiong Gong

Xiong Gong

This work was partially supported by the Mitsubishi Chemical Center for Advanced Materials at UCSB and the Air Force Office of Scientific Research through the MURI Center (“Polymeric Smart Skins”), Charles Lee, Program Officer. Synthesis of the CF3OXD and related tetrahedrally coordinated molecules was supported by a grant to G. Bazan from DuPont Displays. The XPS results were obtained by using the MRL (Material Research Laboratory at UCSB) Central Facilities supported by the National Science Foundation under DMR 96-32716. We thank Prof. W. R. Salaneck of Linköping University (Sweden) for important comments. X. Gong is grateful to Dr. Gang Yu …


Comparison Between Analytical Probabilistic And Computer Simulation Models, Using Current Design Examples, Barry A. Palynchuk Phd Sep 2003

Comparison Between Analytical Probabilistic And Computer Simulation Models, Using Current Design Examples, Barry A. Palynchuk Phd

Barry A. Palynchuk PhD

Closed form analytical expressions have been developed to solve several basic problems related to the hydrologic design of storm water management facilities. The collection of these analytical expressions is referred to as the Analytical Probabilistic Storm Water Models (APSWM). APSWM can be used as an alternative to the design storm simulation models in the design and analysis of storm water management facilities. In this paper, a comparison is made between APSWM and design storm simulation models as applied to an actual design case. Conventional outputs such as runoff volume, peak discharge, and peak discharge from detention ponds are reviewed and …


Measurements Of The Longitudinal Wave Speed In Thin Materials Using A Wideband Pvdf Transducer, Kwang Yul Kim, Wei Zou, Stephen D. Holland, Wolfgang Sachse Sep 2003

Measurements Of The Longitudinal Wave Speed In Thin Materials Using A Wideband Pvdf Transducer, Kwang Yul Kim, Wei Zou, Stephen D. Holland, Wolfgang Sachse

Stephen D. Holland

A flat transducer was constructed, using a 9-mm-thick PVDF (polyvinylidene fluoride) film for generation and detection of high-frequency ultrasonic waves, and used for measurements of the phase velocity of longitudinal waves traveling along the thickness direction in a very thin material. The transducer has a useful wideband frequency characteristic extending from 10 MHz to over 150 MHz. Measurements of the phase velocity of the longitudinal waves are carried out using a 0.212-mm-thick glass slide and a 0.102-mm-thick stainless-steel shim, using water as a coupling medium. The thickness limit for this measurement appears to be approximately 20 mm. The phase velocity …


Optical And Acoustic Habitat Characterization With The Seabed Auv, Hanumant Singh, Ryan Eustice, Oscar Pizarro, Christopher Roman Aug 2003

Optical And Acoustic Habitat Characterization With The Seabed Auv, Hanumant Singh, Ryan Eustice, Oscar Pizarro, Christopher Roman

Christopher N. Roman

The Seabed AUV is an Autonomous Underwater Vehicle (AUV) built to serve as a readily available and operationally simple tool for high resolution imaging. It is a hover-capable vehicle that performs optical sensing with a 12 bit 1280/spl times/1024 CCD camera and acoustic high resolution mapping using an MST 300 kHz sidescan and a 675 kHz pencil beam bathymetric sonar. The AUV has been designed for operations from small vessels with minimal support equipment. It has an operational depth of 2000 meters and at 1 m/s can run for up to 10 hours. In this paper we report on the …


Atp-Independent Contractile Proteins From Plants, Michael Knoblauch, Gundula Noll, Torsten Müller, Dirk Prüfer, Ingrid Schneider-Hüther, Dörte Scharner, Aart Van Bel, Winfried Peters Aug 2003

Atp-Independent Contractile Proteins From Plants, Michael Knoblauch, Gundula Noll, Torsten Müller, Dirk Prüfer, Ingrid Schneider-Hüther, Dörte Scharner, Aart Van Bel, Winfried Peters

Winfried S. Peters

This paper has no abstract; this is the first paragraph. Emerging technologies are creating increasing interest in smart materials that may serve as actuators in micro- and nanodevices. Mechanically active polymers currently studied include a variety of materials. ATP-driven motor proteins, the actuators of living cells, possess promising characteristics, but their dependence on strictly defined chemical environments can be disadvantagous. Natural proteins that deform reversibly by entropic mechanisms might serve as models for artificial contractile polypeptides with useful functionality, but they are rare. Protein bodies from sieve elements of higher plants provide a novel example. sieve elements form microfluidics systems …


Ocena Funkcjonowania Instalacji Oczyszczania Gazów Odlotowych Z Procesu Grafityzacji Elektrod Węglowych W Sgl Carbon S.A. W Nowym Sączu, Marian Mazur, Robert Oleniacz, Marek Bogacki, Przemysław Szczygłowski Aug 2003

Ocena Funkcjonowania Instalacji Oczyszczania Gazów Odlotowych Z Procesu Grafityzacji Elektrod Węglowych W Sgl Carbon S.A. W Nowym Sączu, Marian Mazur, Robert Oleniacz, Marek Bogacki, Przemysław Szczygłowski

Robert Oleniacz

The paper presents a general analysis of the suitability of individual elements of the flue-gas treatment system used in SGL Carbon SA in Nowy Sacz (Poland) for the graphitization process carried out in new LWG furnaces (Castner type). The flue-gas treatment system consisted of two installations: catalytic afterburning and flue-gas desulfurization. The analysis of the suitability of various methods of flue-gas treatment was based primarily on the assessment of the effects of their application, including the reduction of concentrations of selected components in post-graphitizing gases. The work also summarizes the results of evaluation of the functioning of the whole flue-gas …


Modelling And Simulation Of Momentum, Heat, And Mass Transfer In A Deep-Bed Grain Dryer, Istadi Istadi, Johnner P. Sitompul, Siswo Sumardiono Aug 2003

Modelling And Simulation Of Momentum, Heat, And Mass Transfer In A Deep-Bed Grain Dryer, Istadi Istadi, Johnner P. Sitompul, Siswo Sumardiono

Istadi

This article concerns the modelling and simulation of a deep-bed grain dryer in a large diameter-column. Two-dimensional (2D) models of deep-bed grain dryers were built by considering simultaneously momentum, heat, and mass transfer in the drying phase together with coupled heat and mass balance in the grain phase. The dynamic equations are solved numerically by using finite difference method. The momentum equations are applied to simulate pressure drop and velocity field of the drying air across the bed. The mass and heat balance in the two phases determine the profile of temperature and moisture content in both phases. Further, drying …