Kurt Lund Consulting, Del Mar, California, USA
A kernel of grain is modeled as an isothermal sphere, with descriptive differential equations scaled or rendered into non-dimensional form, where moisture transfer is governed by internal diffusivity, not by surface conditions. The time dependent problem is solved with COMSOL and the average non-dimensional moisture content and its time-rate of change are obtained; by regression, these numerical ...
S. Suganthi, M. Anandraj, and L. Sujatha
Department of Electronics & Communication Engineering, Rajalakshmi Engineering College, Chennai, India
Department of Physics, Rajalakshmi Engineering College, Chennai, India
Porous Silicon (PS) can easily be formed by electrochemical etching of silicon in HF based electrolytes at room temperature. Since, PS is compatible with silicon IC technology; it finds lot of applications in the fabrication of MEMS devices. In the current study, we discuss the design of a condenser microphone using a Silicon/ Porous Silicon composite membrane as a movable plate. The performance ...
A. Eed Olamat, U. Hofmann, B. Pohl, and N. Nkemasong
University of Lübeck, Institute for Signal Processing, Lübeck, Germany
In order to investigate the implantation of microprobes into brain tissue, we developed a finite-element and a physical model to replace real biological tissue for mechanical testing. Penetrating forces of a tungsten indenter into a layered structure was investigated with different indentation speeds. Numerical and physical model are in good correspondence to each other and reproduce measured ...
Homogeneous and Inhomogeneous Model for Flow and Heat Transfer in Porous Materials as High Temperature Solar Air Receivers
O. Smirnova, T. Fend, P. Schwaryboezl, and D. Schoellgen
German Aerospace Center, Institute of Technical Thermodynamics, Koeln, Germany
Results of simulations on flow and heat transfer in a porous Silicon Carbide honeycomb structure applied as a solar air receiver are presented. In this application porous materials are put in concentrated solar radiation. Flux densities of up to 1000 MW/m² are reached. Simultanously, ambient air flows through the material to be heated up to temperatures of app. 800°C. This hot air is then used ...
A. Priarone, and S. Lazzari
DIPTEM-TEC, Università di Genova, Genova, Italia; Corresponding Author: email@example.com
DIENCA, Università di Bologna, Bologna, Italia
The effect of the infinite length approximation on evaluating the temperature of the surface of Borehole Heat Exchangers is determined by means of COMSOL Multiphysics. In detail, two 2D models of a BHE are compared: in the first model, the domain is represented by a cross-section of the geometry, while in the second model, it is represented by an axial-section of the geometry and, thus, the BHE ...
Designers of electro-optic modulators and related devices often use separate tools to study the optical and electrical portions of the device. The flexibility of COMSOL Multiphysics makes it possible to construct unified models of EO phenomena including realistic waveguide profiles and anisotropic material properties. We demonstrate the use of the RF Module to compute both RF and optical ...
Assessment of Spatial Variably Saturated Flow by Irrigation Moisture Sensors in 2-Dimensions using the COMSOL Multiphysics 4.1
A. Boluwade, and C. A. Madramootoo
Bioresources Engineering, McGill University
Ste. Anne De Bellevue, QC
This paper reports on the application of COMSOL Multiphysics’ Richard\'s Equation Interface in the assessment of irrigation moisture sensors for detecting the level of water saturation in a spatial variably saturated soil. The Richard\'s Equation (in COMSOL) provides the interface which automates the van Genuchten equation. A hypothetical soil column 4m by 4m was set up with seven irrigation ...
V. S. Nagaraja, N. Suma, and S. L. Pinjare
Nitte Meenakshi Institute of Technology
The tunable capacitor (variable capacitor) is one of the most important and components in filters, Phase shifters, VCO etc. A tunable capacitor can also be built using electro – thermal actuating mechanism. Compared to electro static, tunable capacitors actuated by thermal actuators have several advantages like lower driving voltages. The performance of thermal actuator becomes a key factor ...
S. Logeshkumar, L. Lavanya, G. Anju, and M. Alagappan
PSG College of Technology
Tamil Nadu, India
In the model silicon nanorods are designed as cantilever array and coated with thin film of aluminum or aluminum nitride, to be characterized, thus, adding a detectable mass and altering the cantilever resistance to bending. The simulated results show that when films of different thickness are placed on the cantilever, there is a corresponding change in the resonant frequency and the ...
V. Sista, and E. Bhattarchaya
Microelectronics and MEMS Lab
Department of Electrical Engineering
Indian Institute of technology Madras
A MEMS based Knudsen’s pressure gauge working in the range of 1e-5 mbar to 10 mbar is designed and simulated in COMSOL. The working principle is based on Knudsen’s forces that arise when two plates are held at different temperatures and their separation is comparable to the mean free path of the ambient gas molecules. The forces change the separation between the plates and capacitance between ...