A highly efficient combined multi-effect evaporation-absorption heat pump and vapor-compression refrigeration part 2: Thermoeconomic and flexibility analysis

Janghorban Esfahani, I.,Yoo, C. Pergamon Press 2014 ENERGY Vol.75 No.-

This paper continues Part 1 of our study and develops a thermoeconomic model of the system with low and high pressure compressors. The thermoeconomic model was used to assess the unit cost of the fresh water and cooling and to evaluate the flexibility of the system for fuel allocation from different electricity and heat energy sources. A parametric analysis was carried out to investigate the effects of the RR (refrigerant flow-rate ratio) from the high pressure compressor to the low pressure compressor of the VCR (vapor compression refrigeration) system, the price of steam, and the price of electricity on the product cost rate and the exergy efficiency of the system. The results showed that the system with two compressors had high flexibility to allocate the different energy sources when the availability of the sources was limited for a given value of fresh water and cooling production.

Control performance evaluation of reverse osmosis desalination system based on model predictive control and PID controllers

Janghorban Esfahani, Iman,Ifaei, Pouya,Rshidi, Jouan,Yoo, ChangKyoo Balaban Publishers 2016 Desalination and Water Treatment Vol. No.

Design of Hybrid Renewable Energy Systems with Battery/Hydrogen storage considering practical power losses: A MEPoPA (Modified Extended-Power Pinch Analysis)

Janghorban Esfahani, Iman,Ifaei, Pouya,Kim, Jinsoo,Yoo, ChangKyoo Elsevier 2016 ENERGY Vol.100 No.-

<P><B>Abstract</B></P> <P>EPoPA (Extended-Power Pinch Analysis) is a technique to integrate Hybrid Renewable Energy Systems with Battery/Hydrogen storage. Power losses of the storage components due to their inefficiency have not been considered in EPoPA as of yet. This study proposes the MEPoPA (Modified Extended-Power Pinch Analysis) to modify EPoPA to consider the power losses in Hydrogen Storage System components. The MEPoCC (Modified Extended-Power Composite Curve) and MEPoSCT (Modified Extended-Power Storage Cascade Table) are introduced as the MEPoPA graphical and numerical tools to determine the minimum targets of Required External AC (Alternating-Current) and DC (Direct-Current) Electricity Sources as well as the Hydrogen Storage System component sizes. The sensitivity analysis is conducted to investigate the effect of various Hydrogen Storage System components, such as the inverter, converters, Fuel Cell, Electrolyzer and rectifier efficiencies, on the Hydrogen Tank Electricity Capacity and the Required External AC and DC Electricity Sources. The graphical and numerical results of the MEPoPA obtained from a case study showed that the system designed by MEPoPA requires 62.19% more outsourced electricity than the system designed by EPoPA. This means that the integration potential of the Renewable Energy System with Battery/Hydrogen storage is decreased with an increase in the power losses of the storage system.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Construction of Modified Extended-Power Composite Curve. </LI> <LI> Construction of Modified Extended-Power Storage Cascade Table. </LI> <LI> Investigation of the various component efficiencies on the hydrogen tank capacity. </LI> <LI> Optimal systems comparison with and without power losses. </LI> <LI> Power losses decrease the integration potential of the battery/hydrogen system. </LI> </UL> </P>

Extended-power pinch analysis (EPoPA) for integration of renewable energy systems with battery/hydrogen storages

Janghorban Esfahani, Iman,Lee, SeungChul,Yoo, ChangKyoo Elsevier 2015 RENEWABLE ENERGY Vol.80 No.-

<P><B>Abstract</B></P> <P>An extended-power pinch analysis (EPoPA) is proposed as a means of extending the power pinch analysis (PoPA) for optimal design of renewable energy systems with battery and hydrogen storage (RES-BH). The EPoPA concept is based on the storage of wasted electricity that cannot be stored by the battery bank designed by PoPA. This energy is stored in the form of hydrogen and is discharged in the form of electricity when the external electricity source is needed. EPoPA graphical and numerical tools are introduced to determine the minimum required external electricity source, wasted electricity sources, and appropriate hydrogen storage system capacity of the RES-BH system during first and normal operation years. Furthermore, the integration of the RES-BH system with a diesel generator as a high reliable system is investigated in view point of economic. The optimal sizes of diesel generator and hydrogen storage system components, such as electrolyzer, fuel cell and hydrogen tank are obtained with the minimization of the total annual cost (TAC) of the system. The implementation results of the EPoPA tools on three possible case studies indicate that EPoPA, unlike other process integration methodologies such as PoPA, is able to optimally design RES-BH systems.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Proposing the extended-power pinch analysis (EPoPA) for renewable energy systems. </LI> <LI> Definition of extended-power composite curve (EPoCC) as the graphical approach. </LI> <LI> Proposition of extended-power cascade analysis as the numerical tool. </LI> <LI> Determination of the optimal hydrogen storage system and diesel generator sizes. </LI> <LI> Implementation of proposed EPoPA for three possible yearly case studies. </LI> </UL> </P>

A high efficient combined multi-effect evaporation-absorption heat pump and vapor-compression refrigeration part 1: Energy and economic modeling and analysis

Janghorban Esfahani, I.,Kang, Y.T.,Yoo, C. Pergamon Press 2014 ENERGY Vol.75 No.-

A novel combined system that combines a MEE-ABHP (multi-effect evaporation-absorption heat pump) with a VCR (vapor-compression refrigeration) cycle is proposed to simultaneously generate cooling and fresh water. In the combined system, the condenser of the VCR system is replaced by the MEE-ABHP system, where a portion of the fresh water produced in the last effect of the MEE (multi-effect evaporation) system is used as the refrigerant for the VCR system. In Part 1 of this two-part paper, model-based energy and cost analysis is developed to quantify and qualify the performance of the combined system. Parametric analysis is carried out to investigate the effects of absorber pressure (P<SUB>A</SUB>), temperature difference between effects of the MEE subsystem (ΔT<SUB>MEE</SUB>), temperature of the strong solution from absorber (T<SUB>1</SUB>), and temperature of the weak solution from generator (T<SUB>4</SUB>) on the performance of the system. In Part 2, thermo-economic and exergy analysis is conducted to evaluate the flexibility of the system for fuel allocation from different available power and heat energy sources. The results of Part 1 showed that the combined system can save 57.12%, 5.61%, and 25.6% in electric power, heat energy, and total annual cost compared to the stand-alone VCR and MEE-ABHP systems, respectively.

Energy Saving of Combined Fresh Water and Cold Generation System by Compressor Intercooler Waste Heat Recovery

Iman Janghorban,Hongbin Liu,Payam Ghorbannezhad,ChangKyoo Yoo 제어로봇시스템학회 2011 제어로봇시스템학회 국제학술대회 논문집 Vol.2011 No.10

Fresh water and cold which are produced by desalination and cooling processes are simultaneously utilized in many factories and industries. Energy saving can be possible by integration of desalination and cooling systems. This paper contributes to a new integration scheme of the reverse osmosis (RO) and refrigeration systems. Compressor intercooler and condenser waste heat are recovered to increase the intake seawater temperature, which causes decrease in RO pump usage and compressor power consumption. The RO system and refrigeration cycle is modeled. Experimental design of central composite design (CCD) is applied to determine the input decision variables, which are consist of intercooler pressure and heat source temperature (TH) responses variables are coefficient of performance (COP) and power consumption of reverse osmosis (PRO). Multi objective optimization to minimize PRO and maximize COP is performed using genetic algorithm (GA) over the ANN model. The input decision variables corresponding to Pareto optimal sets are presented minimum as the optimal design parameters.

Exergetic Analysis of Power and Freshwater Cogeneration Systems

Iman Janghorban Esfahani,ChangKyoo Yoo 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10

This study proposes a systematic approach of energy and exergy analysis of reverse osmosis (RO) desalination system combined with the gas turbine power plant (GT). Three systems of RO for producing freshwater and a gas turbine for generating the power for the pumps and other equipments are compared in energy and exergy aspects. The first system mechanically couples RO with the power plant; while the second and third systems couples are mechanical as well as thermal, using a refrigeration cycle and compressor intercooler. Energy and exergy efficiencies and the rates of exergy destruction for all of the streams and components are identified. The third system with compressor intercooler showed the best performance among three systems, which increases energy and exergy efficiencies by 8.42% and 12.07%, respectively, compared with the first system as the base system.

Powder Metallurgy : STUDIES ON THE FORMATION OF SiC WHISKERS FROM RICE HULL

K . Janghorban,H . R . Tazesh 대한금속재료학회 ( 구 대한금속학회 ) 1995 Advanced Material and Processing Vol.1 No.-

Numerical assessment of post-tensioned slab-edge column connection systems with and without shear cap

Farshad Janghorban,Abdollah Hoseini 사단법인 한국계산역학회 2018 Computers and Concrete, An International Journal Vol.22 No.1

Introduction of prestressed concrete slabs based on post-tensioned (PT) method aids in constructing larger spans, more useful floor height, and reduces the total weight of the building. In the present paper, for the first time, simulation of 32 two-way PT slab-edge column connections is performed and verified by some existing experimental results which show good consistency. Finite element method is used to assess the performance of bonded and unbonded slab-column connections and the impact of different parameters on these connections. Parameters such as strand bonding conditions, presence or absence of a shear cap in the area of slab-column connection and the changes of concrete compressive strength are implied in the modeling. The results indicate that the addition of a shear cap increases the flexural capacity, further increases the shear strength and converts the failure mode of connections from shear rigidity to flexural ductility. Besides, the reduction of concrete compressive strength decreases the flexural capacity, further reduces the shear strength of connections and converts the failure mode of connections from flexural ductility to shear rigidity. Comparing the effect of high concrete compressive strengths versus the addition of a shear cap, shows that the latter increases the shear capacity more significantly.

A Cost Approach for Optimization of a Combined Power and Thermal Desalination System through Exergy and Environmental Analysis

Esfahani, I. Janghorban,Kim, J. T.,Yoo, C. K. American Chemical Society 2013 INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH - Vol.52 No.32

<P>In this Article, a systematic approach of cost analysis and optimization for combining the multieffect thermal vapor compression (METVC) desalination system with the gas turbine power plant (GT) was proposed on the basis of thermodynamic, economic, and environmental attributes. The total annual cost (TAC) of the combined system, including annual capital and operating costs, was modified to define an efficient cost objective function by adding the exergy destruction cost as a lost opportunity cost, and environmental emissions cost as a damage cost of the system to the operating cost. A parametric analysis was conducted to evaluate the effects of the key thermodynamic parameters for combining the GT and METVC systems, including the gas turbine inlet temperature (TIT), the HRSG outlet temperature (HOT), and the temperature difference between the effects of the METVC system (Δ<I>T</I><SUB>METVC</SUB>) on the modified total annual cost (MTAC). The parameter optimization was achieved using a genetic algorithm (GA) to find the optimal key thermodynamic parameters with minimization of the MTAC of the combined system. In addition, the methodology was applied to optimize the combining of a METVC desalination system with a GT power plant located in Mahshar, Iran. The optimization results indicated that the METVC systems with less than five effects cannot be combined with the current GT power plant because the combined systems cannot produce the power and fresh water requirements. Among the combined systems with more than four effects in the METVC system, the combined system with five effects in the METVC system was selected as the best system, which can produce 28 543 m<SUP>3</SUP>/day fresh water and 127 MW power, respectively, and reduce the NO<SUB><I>x</I></SUB> emission by 3.6% as compared to the current power plant.</P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ie401068c'>ACS Electronic Supporting Info</A></P>