15 documents found, page 1 of 2

On the enhancement of heat transfer in a backward-facing step using porous baffles

The backward-facing step is a geometry often used not only to investigate the accuracy and performance of numerical models, but also to analyse fundamental flow and heat transfer characteristics, and the impact of different configurations for the most diverse problems primarily due to its similitude to tangible and more complex geometries. One of the fields of interest is its use for heat transfer problems, whi...

MATHEMATICAL MODELLING AND SIMULATION TECHNIQUES REVIEW FOR HYBRID PHTOVOLTAIC ...

In this work, solar hybrid photovoltaic thermal (PVT) panel’s different mathematical modelling and simulation techniques are described. Mathematical and thermal model development and simulation technique is considered as the initial conditions to simulate the system’s behavior. This article discusses about improved modelling and implementation technique of hybrid PVT technology to enhance the panels effective e...

Modeling and Sensitivity Analysis of Hybrid Solar System

Efficiency in the solar energy system is obtained by studying, modeling and analyzing the emerging hybrid photovoltaic thermal (PVT) technology that produces simultaneous electrical and thermal energy [1]. This paper describes the study and analyses of mathematical [2] model including thermal and electrical modeling [3-4] to obtain the effective efficiency of the hybrid photovoltaic thermal system.The important...

Geometric optimization of linear Fresnel reflector solar collector using a gene...

In this work, the optimization of a Linear Fresnel Reflector solar concentrator through a parallelized Multi-offspring Genetic Algorithm is presented. An analytical description of the concentrator was developed and used to compute specific annual collected energy; this is the fitness function to be maximized. Selection, reproduction, and mutation operators were defined to produce diversity of individuals. Eliti...

COVID-19: The Invisible War

Threshold Estimation for Least-Squares Fitting in Impedance Spectroscopy

The estimation of circuit component values in impedance spectroscopy applications usually requires the minimization of a least-squares cost function. Independently of the minimization method used, a threshold value should be used as a stopping criteria for the iterative minimization procedure. This paper presents a new estimator for the threshold value to be used in least-squares minimization problems applied t...

Digital Filter Performance for Zero Crossing Detection in Power Quality Embedde...

Power quality analysis involves the measurement of quantities that characterize the power supply waveforms such as RMS value, frequency, harmonic and inter-harmonic distortion or the presence of transients. The measurement of these quantities is regulated by internationally accepted standards from IEEE or IEC. In particular, for the evaluation of frequency and RMS values, the standard suggests the detection of ...

Comparison of harmonic estimation methods for power quality assessment

Power quality is regulated by international accepted standards from IEEE and IEC. One of the parameters that is defined in the standards is the harmonic distortion. The grouping method is the standard-advised method to evaluate harmonics but other approaches can be used. In this paper, three different methods are compared considering memory requirements, relative time consumption and the uncertainty of the harm...

Low Pass Digital Filter Delay Compensation for Accurate Zero Cross Detection in...

Zero crossing detection with a low pass filter is a common method used to estimate a signal frequency or period when the signal is affected by noise, harmonics or other parasitic frequencies. This method is often used in power quality measurements due to the typical disturbances of the electrical power grid signals and is for example, suggested in IEC 61000-4-30 for power quality frequency estimation. Zero cros...

Artificial Bee Colony Algorithm for Peak-to-Peak Factor Minimization in Periodi...

Minimization of the peak-to-peak factor in multiharmonic signals is highly desirable in many signal processing applications such as impedance spectroscopy and acoustic signal generation. This minimization allows optimized signal to noise ratio within a given signal amplitude range. Careful selection of the phases of each harmonic of a multiharmonic signal may lead to much better peakto- peak factors when compar...