In this paper, a multi-cylinder, internal combustion engine model is presented. The paper is focused on a simple modular, physically based and lumped parameter (zero dimensional) approach, leading to a complete and coherent model structure. The model is conceived to be used with general purpose simulation software, as MATLAB/Simulink. The mean value outputs of the model (pressure, temperature, ...

A simple method is presented for describing the sound transmission in a duct containing an array of lined resonators. The impedance of a resonator element is calculated, including the effect of the lining and the duct is modeled as a onedimensional waveguide with lumped impedances. An expression for the TL is derived from considerations of pressure and mass flow continuity along the duct. Exper...

This work details the preliminary development and testing of a novel, single input – single output (SISO) resonant microsensor, which exploits vibration localization in a coupled-oscillator architecture to allow for the detection of multiple analytes with a single platform. The work includes a brief description of a preliminary sensor design and its operating principles, an outline of a lumped ...

The effects of compressor speed variation on the heat transfer inside a speed controlled compressor were investigated in this study. Based on the lumped capacitance ntethod, the temperatures of the compressor components, the oil, and the refrigerant gas within the shell were modeled and simulated on a relative scale. A diffenmt heat transfer coefficient correlation was developed to evaluate the...

The dynamic impedance of a sphere oscillating in an elastic medium is considered. Oestreicher's [J. Acoust. Soc. Am. 23, 707-714 (1951)] formula for the impedance of a sphere bonded to the surrounding medium can be expressed in a relatively simple form in terms of three lumped impedances associated with the displaced mass and the longitudinal and transverse waves. If the surface of the sphere s...

In this study, the dispersion of an infinite shear beam with a lumped mass connected at periodic distances and resting on elastic foundation was examined. The effect periodicity in finite region masses wave propagation investigated through one-dimensional model. relationship for Bragg scattering, which consists masses, derived using transfer matrix method. Subsequently, to evaluate parameters s...

Thermodynamic and dynamic analyses of a variable speed reciprocating compressor have been conducted to investigate performance changes and some data related to the reliability problems such as valve velocity, PV value, bearing loci, Sommerfeld number, minimum film thickness etc. The first law of thermodynamics, continuity equations, valve dynamic equations and Helmholtz resonator method were us...

We consider the initial boundary value problem for the homogeneous heat equation, with homogeneous Dirichlet boundary conditions. By the maximum principle the solution is nonnegative for positive time if the initial data are nonnegative. We complement in a number of ways earlier studies of the possible extension of this fact to spatially semidiscrete and fully discrete piecewise linear finite e...

THE MATHEMATICAL MODEL AND NUMERICAL SIMULATION OF THE HEAT PUMP SYSTEM 1. COLLEGE OF APPLIED SCIENCES – SUBOTICA TECH, SERBIA 2. BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICS, HUNGARY ABSTRACT: In this paper water-water heat pump is analyzed using a computer simulation. The simulation program is based upon steady state mathematical models of the refrigeration system components. The numerical...

This paper presents a symbolic and recursive calculation of the stiffness and mass matrices of parallel robots. In order to reduce the computational time required for simulating the elastodynamic behavior of robots, it is necessary to minimize the number of operators in the symbolic model expression. Some algorithms have been proposed for the rigid case or for parallel robots with lumped spring...