Hoseyn Sayyaadi | K. N. Toosi University of Technology (original) (raw)

Papers by Hoseyn Sayyaadi

International Journal of Hydrogen Energy, Jun 1, 2023

Energy Conversion and Management, Nov 1, 2020

Energy Conversion and Management, Sep 1, 2022

Sustainable Energy Technologies and Assessments, Oct 1, 2021

Abstract Numerical simulations of photovoltaic solar panels are performed using temperature-depen... more Abstract Numerical simulations of photovoltaic solar panels are performed using temperature-dependent layer properties. The results are compared with experimental data recorded from a 50 W mono-crystalline panel and a 50 W poly-crystalline panel. The comparison shows that, for both panels, introducing temperature dependencies in the layer properties can significantly improve the accuracy of numerical simulations. On a sample day in August 2019, the mean absolute error in power prediction is found to decrease from 9.13 to 4.32% for the mono-crystalline panel and from 9.49 to 5.55% for the poly-crystalline panel, representing accuracy improvements of 52.7% and 41.5%, respectively. On an annual basis, the accuracy of estimating the power generated by the mono- and poly-crystalline panels improves by 52.8% and 41.4%, respectively. Finally, it is found that as the standard deviation of the temperature distribution on the panel increases, so does the effect of the temperature-dependent layer properties. This study highlights the need to account for the temperature dependencies of the different layer properties when numerically simulating photovoltaic panels.

International Journal of Solar Thermal Vacuum Engineering, Aug 25, 2021

Sustainable Energy Technologies and Assessments, Jun 1, 2021

Abstract Dynamic multi-objective optimization (DMOO) is implemented on a water-based cooling syst... more Abstract Dynamic multi-objective optimization (DMOO) is implemented on a water-based cooling system to enhance the performance of a 50 W polycrystalline-based solar photovoltaic (PV) module. The DMOO is conducted under the climatic conditions of Tehran, Iran, with the aim of maximizing the power output while minimizing the amount of cooling water consumed. The results of the DMOO are compared against those of a no-cooling condition (NCC) and a constant water flow (CWF) condition of 0.1 LPM. Compared with CWF, DMOO is found to produce a 64.73% increase in the annual energy production and a 41.98% decrease in water usage over an entire year. Furthermore, compared to NCC, DMOO is able to reduce the average and maximum temperatures of the PV module by 54.07% and 61.02%, respectively in a year; these figures are 16.63% and 17.37% better than those of CWF. Moreover, on an annual basis, DMOO is found to reduce the difference between the average and maximum PV temperatures by 79.79% and 54.53% relative to NCC and CWF, respectively. This study shows that the performance of a PV module can be improved significantly by applying DMOO to its water-based cooling system.

Sustainability, Nov 22, 2022

Engineering Analysis with Boundary Elements

Journal of Cleaner Production

Journal of Thermal Analysis and Calorimetry, 2021

The purpose of this study is to utilize artificial neural network (ANN), as one of the most power... more The purpose of this study is to utilize artificial neural network (ANN), as one of the most powerful artificial intelligence methods, for modeling stream function (f) and the dimensionless temperature (θ) for the considered problem. The problem that is investigated here is flowing a Newtonian fluid on a permeable flat surface. The Homotopy Perturbation Method (HPM) recently developed by the authors for this problem is utilized to provide enough number of the input data. The best ANN is found for each of the two indicated outputs. Then, the best ANN model for each output is utilized to investigate the impact of changing the similarity variable in the range 0.0 to 10.0 on prediction error of the two mentioned outputs. Four values for porosity, which are 0.2, 0.5, 0.8, and 1.0, are investigated. According to the findings, an almost quadratic relation for changes prediction error of f as a function of η is seen, whereas after a sudden drop, the error in prediction of θ declines linearly. Moreover, for the whole range, and for both outputs, the error remains in an acceptable range, which verifies the good accuracy of ANN.

Renewable Energy, Dec 1, 2013

ABSTRACT In the recent years, numerous studies have been done on Stirling cycle and Stirling engi... more ABSTRACT In the recent years, numerous studies have been done on Stirling cycle and Stirling engine which have been resulted in different output power and engine thermal efficiency analyses. Finite speed thermodynamic analysis is one of the most prominent ways which considers external irreversibilities. In the present study, output power and engine thermal efficiency are optimized and total pressure losses are minimized using NSGA algorithm and finite speed thermodynamic analysis. The results are successfully verified against experimental data.

Applied Thermal Engineering, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Applied Thermal Engineering, Oct 1, 2017

Heat and mass recirculations strategies for improving the thermal efficiency and environmental em... more Heat and mass recirculations strategies for improving the thermal efficiency and environmental emission of a gas-turbine cycle,

Applied Thermal Engineering, Apr 1, 2016

Please cite this article as: Mohammad Tahmasebzadehbaie, Hoseyn Sayyaadi, Efficiency enhancement ... more Please cite this article as: Mohammad Tahmasebzadehbaie, Hoseyn Sayyaadi, Efficiency enhancement and NO x emission reduction of a turbo-compressor gas engine by mass and heat recirculations of flue gases,

Energy Conversion and Management, Mar 1, 2019

The model uses the conjugate method and calculates a more realistic boundary condition on the mem... more The model uses the conjugate method and calculates a more realistic boundary condition on the membrane, and the separating walls. This boundary condition is calculated by the simultaneous solution of momentum, energy, and mass transfer equations of flows. To increase accuracy, flows are considered hydrodynamically, thermally, and in concentration to be developing. The validation results showed that the model can accurately predict the humidity ratio change of the supply air with less than 3.22% error. Afterward, four membrane-based liquid desiccant dehumidifiers including cross-flow, counter-flow, internally cooled and developed internally cooled are modeled and investigated. The dehumidifiers performances are compared at different inlet air conditions, and the results indicate that the developed internally cooled dehumidifier has the highest effectiveness.

Energy Conversion and Management, Oct 1, 2019

A perforated-type regenerative type evaporative humidifier is presented which has an innovative f... more A perforated-type regenerative type evaporative humidifier is presented which has an innovative flow configuration. Such a flow configuration prevents the moist air from achieving quick saturation, and as a result, it maximizes the humidification capacity. A control volume formulation based mathematical model is developed which is simulated using nested numerical techniques having coupled boundary conditions. The system performance is gauged by three objective functions, namely humidification capacity, total electrical energy consumption, and efficiency factor. A detailed sensitivity analysis is carried out to report the system performance with respect to outdoor air conditions, geometric parameters, and operating conditions. Afterwards, an optimization study is conducted for 11 different climatic zones all around the world. An optimized humidification capacity of ∼32 g water vapor /min, energy consumption of 2.1 kW, and an efficiency factor of ∼40% is reported for the proposed configuration for dry climatic zone which is 64%, 11%, and 26% more than a direct-contact evaporative humidifier respectively. It is also found that the optimal ranges for channel length, channel width, channel height, and water temperature, are 900-1000 mm, 55-60 cm, 7-8 mm, and 60-70°C, respectively.