The comparison of various gas turbine inlet aircooling methods for various ambient condition trough energy and exergy analysis

The strong influence of climate conditions on gas turbine behavior is well known. During the summer season the output of gas turbines falls to a value that is less than the rated output under high temperature conditions. Cooling the turbine inlet air can increase output power considerably, because cooled air is dense, giving the turbine a higher mass flow rate and resulting in increased turbine output and efficiency. This study is to use the energy and exergy analysis method to evaluate the air cooling method used for enhancing the gas turbine power plant. In addition, the effect of inlet air cooling method on the output power, exergy efficiency and exergy destruction have been analyzed. Also at the end of the paper the comparison of two mentioned methods has been investigated

A Novel Energy Management Control Technique for PV-Battery System in DC Microgrids

This paper presents a new energy management control technique for PV-Battery system used in DC microgrids. The proposed control technique is performed based on a droop control algorithm that maintains DC-bus voltage in a desirable and required range adaptively. Tightly Regulating the bus voltage In the islanded mode of operation is very challenging. However, the proposed control method by introducing a nonlinear droop profile with four adaptive parameters shows its superiority. Adaptive parameters determined by the non-linear optimal algorithms. Tightly regulating the DC bus voltage during extensive changes in demand loads/sources within a DC Micro Grid is the responsibility of the adaptive parameters. Stability of the proposed method in the whole system for a very broad range of operating conditions are proved. Simulation results along with the experimental results verify the feasibility of the proposed approach while demonstrate its superior performance compared to the conventional control method

An exergy-based multi-objective optimisation model for energy retrofit strategies in non-domestic buildings

While the building sector has a significant thermodynamic improvement potential, exergy analysis has been shown to provide new insight for the optimisation of building energy systems. This paper presents an exergy-based multi-objective optimisation tool that aims to assess the impact of a diverse range of retrofit measures with a focus on non-domestic buildings. EnergyPlus was used as a dynamic calculation engine for first law analysis, while a Python add-on was developed to link dynamic exergy analysis and a Genetic Algorithm optimisation process with the aforementioned software. Two UK archetype case studies (an office and a primary school) were used to test the feasibility of the proposed framework. Different measures combinations based on retrofitting the envelope insulation levels and the application of different HVAC configurations were assessed. The objective functions in this study are annual energy use, occupants' thermal comfort, and total building exergy destructions. A large range of optimal solutions was achieved highlighting the framework capabilities. The model achieved improvements of 53% in annual energy use, 51% of exergy destructions and 66% of thermal comfort for the school building, and 50%, 33%, and 80% for the office building. This approach can be extended by using exergoeconomic optimisation

Thermodynamic modeling and exergy optimization of a gas turbine power plant

Due to the importance of increasing power plants performance in Iran Exergy analysis is a common way for these cycles, Thus For this analysis first each part of gas Turbine Plant were modeled by thermodynamic approach then The effect of changing in the inlet turbine temperature on the exergy efficiency and exergy destruction in this plant was evaluated. The results show that the exergy efficiency of the combustion chamber is much lower than that of other plant components due to chemical reaction and the large temperature difference between the burners and working fluid. In addition, these calculations are performed for 50 and 75% G.T base load and results show that the exergy destruction when G.T work in base load is more than full load. More ever the optimizations process has been follow in this paper, therefore in this regard the economic objective function has been defined and minimized

Effects of air compressor pressure ratio on exergy efficiency, cost and environment of a Combined Cycle Power Plant

This work covers energy and exergy, and exergoeconomic and environmental of a Combined Cycle Power Plant (CCPP). To assess the effects of air compressor pressure ratio on efficiency, economic and environment of the system a parametric study is performed. To have reasonable results, the air compressor pressure ratio is varied while all other design parameters are kept constant. Results show by increasing the air compressor pressure ratio the exergy efficiency of gas cycle is increased while the total efficiency is reduced. Consequence, the total cost and CO2 emission are increased

Utilizing microfluidics for visualization of multiphase flow in coal cleats

The aim of this thesis is to implement a microfluidic approach to visualize, analyze, and measure flow in coal seam gas reservoirs. Novel experimental platforms are introduced, which enhances the analysis of multiphase flow in coal seam gas reservoirs. Coal cleat networks are captured by employing micro-computed tomography (micro-CT) imaging, and microfluidic chips are fabricated based on the cleat images. The flow of water and gas in coal cleats are visualized and the displacement efficiencies are quantified. Relative permeability which is an important parameter in the optimization of methane gas extraction is measured via a microfluidic approach and is validated with literature values and pore network simulations of the original 3D coal cleat network. We observed that relative permeability in coal is highly related to the coal cleat structure and geometry. To mimic a realistic scenario of flow in coal cleats, not only the cleat network structure and wettability are important, but also the surface characteristics of coal cleats have to be considered. Hence, a geomaterial microfluidic chip called “Coal-On-a-Chip” (COC) is introduced and developed for the microfluidic experiments. The COC pattern is derived from the micro-CT images of the same coal lithotype and etched on a flat surface of the coal sample. The fabrication method and important considerations of the processes are explained and discussed. Utilizing the geomaterial microfluidic chip, we observed that coal has a highly heterogeneous wettability. The COC provides a tool for more realistically investigations of the flow displacement within coal seam gas reservoirs. This thesis also provides a comparison of the roughness data, wettability and sorption capacity for coal bright and dull band lithotypes. Utilizing microfluidics experiments, the flow in bright and dull bands are visualized and studied. In addition, a flow scenario is investigated in which gas is transported through coal regions that have parallel and adjacent lithotypes. It is visualized that less gas recovery obtains from cleat structures with mixed-wettability. Overall, this work provided insights into transport properties unique to coal through direct visualization and introduced a platform which increases the reliability of coal-related experiments

Modeling and multi-objective exergy based optimization of a combined cycle power plant using a genetic algorithm

In this study, a comprehensive thermodynamic modeling of a dual pressure combined cycle power plant is modeled. Also, to ensure the developed code, results are compared with an actual data taken from one of the Iranian power plant. The combined cycle power plant is equipped with a duct burner. In second part, by considering number of decision variables, the objective function is optimized. To have a better understanding and optimal design of the system, an optimization is performed. In our multi-objective optimization, first objective function comprises a set of component costs, the fuel cost injected into the combustion chamber, duct burner cost and the cost of exergy destruction. Second objective function is cycle exergy efficiency. Therefore, multi-objective optimization of this cycle is carried out using a computer simulation code written by using the genetic algorithm approach. Finally, the effect of cycle key parameters on these two objective functions is investigated. The results show that gas turbine temperature, compressor pressure ratio and pinch point temperatures are significant design parameters. It means that any changes in these design parameters lead to a drastic change in objective functions

An overview of renewable hydrogen production from thermochemical process of oil palm solid waste in Malaysia

Hydrogen is one of the most promising energy carriers for the future of the world due to its tremendous capability of pollution reduction. Hydrogen utilization is free of toxic gases formation as well as carbon dioxide (CO2) emission. Hydrogen production can be implemented using a wide variety of resources including fossil fuels, nuclear energy and renewable and sustainable energy (RSE). Amongst various RSE resources, biomass has great capacity to be employed for renewable hydrogen production. Hydrogen production from palm solid residue (PSR) via thermochemical process is a perfect candidate for waste-to-well strategy in palm oil mills in Malaysia. In this paper, various characteristics of hydrogen production from thermochemical process of PSR includes pyrolysis and gasification are reviewed. The annual oil palm fruits production in Malaysia is approximately 100 million tonnes which the solid waste of the fruits is capable to generate around 1.05 × 1010 kgH2 (1.26 EJ) via supercritical water gasification (SCWG) process. The ratio of energy output to energy input of SCWG process of PSR is about 6.56 which demonstrates the priority of SCWG to transform the energy of PSR into a high energy end product. The high moisture of PSR which is the most important barrier for its direct combustion, emerges as an advantage in thermochemical reactions and highly moisturized PSR (even more than 50%) is utilized directly in SCWG without application of any high cost drying process. Implementation of appropriate strategies could lead Malaysia to supply about 40% of its annual energy demand by hydrogen yield from SCWG of PSR

دراسة تأثير تعديل التعصب الديني على نية السلوك الأخلاقي للمستهلكين، مجال الدراسة: مستهلكو المواد الغذائية في مدينة أصفهان

سابقه و هدف: اخلاق در آموزه‌های دینی جایگاه رفیعی دارد و امروزه شاهد توجه به اخلاق در رفتارهای مصرف‌کننده هستیم. پژوهش حاضر با هدف بررسی نقش تعدیل‌گر تعصب مذهبی بر قصد رفتار اخلاقی مصرف‌کنندگان، به انجام رسیده است. روش کار: این پژوهش از لحاظ هدف کاربردی و از نظر روش در زمرۀ تحقیقات توصیفی-پیمایشی قرار دارد. جامعۀ آماری تمامی مصرف‌کنندگان مواد غذایی شهر اصفهان در پاییز و زمستان سال 1395 بودند. با توجه به حجم جامعۀ نامحدود، از فرمول نمونه‌گیری کوکران استفاده شد؛ بنابراین، حجم نمونۀ آماری با استفاده از روش نمونه‌گیری تصادفی ساده و در نظر گرفتن سطح خطای 07/0، 196 نفر در نظر گرفته شد. ابزار گردآوری اطلاعات در این پژوهش، پرسش‌نامۀ استاندارد بود که پایایی آن با استفاده از ضریب آلفای کرونباخ برابر 852/0 محاسبه و تأیید شد. برای تجزیه ‌و تحلیل داده‌هایِ جمع‌آوری‌شده از روش مدل‌سازی معادلات ساختاری استفاده شد. در این پژوهش همۀ موارد اخلاقی رعایت شده است و مؤلفان مقاله هیچ‌گونه تضاد منافعی گزارش نکرده‌اند. یافته‌ها: نتايج پژوهش حاکی از این است که نگرش؛ هنجارهای ذهنی، اخلاقی و توصیفی و همچنین کنترل رفتاری ادراک‌شده بر قصد رفتار اخلاقی تأثیر معنی‌داری داشت و در نهایت نیز نقش تعدیل‌گر تعصب مذهبی تأیید شد. نتیجه‌گیری: بر اساس یافته­‌ها می­‌توان گفت با وجود اینکه جامعۀ ایران جامعه‌ای مذهبی است؛ مصرف­کنندگان، فارغ از هرگونه گرایش و تعصب مذهبی، به رفتار اخلاقی گرایش دارند و این مسئله بیشتر ریشه در هنجارهای حاکم بر فرد دارد. در این زمینه، بررسی و فهم هنجارهای حاکم در تغییر الگوی رفتار اخلاقی مصرف‌کنندگان اهمیت بسیاری دارد.   استناد مقاله به این صورت است:Nikraftar T, Hosseini E, Agheli M, Moslemi-Kaviri M. Investigating the Moderating Role of Religiosity in Consumers’ Ethical Behavior: A Case Study of Food Consumers in Isfahan. Journal of Pizhūhish dar dīn va salāmat. 2020;6(3):18-30. https://doi.org/10.22037/jrrh.v6i3.24966  Background and Objective: Ethics have a high positions in religious teachings, and today they are considered in consumer behavior. The present study was an attempt to investigate the role moderating of religiosity in consumers’ ethical behavior. Methods: This research is applied in terms of purpose and descriptive survey-based in terms of method. The statistical population of the study included all food consumers in Isfahan in autumn and winter in 2016. Participants the Cochran’s sampling formula was used considering the unlimited number of participants. 196 participants were accordingly selected by random sampling method and taking into account 0.07 error level. The instrument used for collecting data was a standard questionnaire. The reliability of questionnaire was analyzed using Cronbach’s alpha, which was found to be 0.852 and confirmed. In this study, all ethical considerations have been observed and no conflict of interest was reported by the authors. Results: The results indicated that attitude, subjective norms, ethical norms, descriptive norms and perceived behavioral control have a significant effect on ethical behavior intention, and ultimately, the moderating role of religious bias was approved. Conclusion: Despite the fact that Iranian society is a religious community, consumers, regardless of any tendency and religious prejudice, tend to behave ethically, and this is more rooted in the norms governing the individuals. In this regard, it is important to examine the norms affecting the patterns of consumer ethical behavior.   Please cite this article as: Nikraftar T, Hosseini E, Agheli M, Moslemi-Kaviri M. Investigating the Moderating Role of Religiosity in Consumers’ Ethical Behavior: A Case Study of Food Consumers in Isfahan. Journal of Pizhūhish dar dīn va salāmat. 2020;6(3):18-30. https://doi.org/10.22037/jrrh.v6i3.24966  خلفية البحث وأهدافه: تتمتع الأخلاق بمكانة رفيعة في التعاليم الدينية، ونشهد في هذه الأيام الاهتمام بالأخلاق في سلوك المستهلكين. وقد تمت الدراسة الحاضرة بهدف دراسة تأثير تعديل التعصب الديني على نية السلوك الأخلاقي للمستهلكين. منهجية البحث: تعتبر هذه الدراسة بلحاظ الهدف من النوع العملي التطبيقي، وبلحاظ المنهج تدخل في زمرة الدراسات الوصفية-التدقيقية. وتشمل الدراسة جميع مستهلكي المواد الغذائية لمدينة أصفهان في خريف وشتاء عام 2016. ومع ملاحظة الحجم غير المحدود لمجال الدراسة فقد تم الاستفادة من معادلة نمذجة كوكران. وبناءً على هذا، فبعد الاستعانة بطريقة النمذجة العشوائية البسيطة ومع الأخذ بعين الاعتبار بمستوى خطأ يبلغ 0/07 فقد بلغ حجم النموذج الإحصائي 196 شخصاً. وقد كانت الأدوات المستخدمة في جمع البيانات خلال هذه الدراسة عبارة عن اختبار معياري تبلغ موثوقيته التي تم تقييمها وتأييدها بالاستفادة من ثابت آلفاي كرونباخ 0/852. كما تم الاستفادة من طريقة نمذجة المعادلات الهيكلية في تفكيك وتحليل البيانات التي تم جمعها. وقد تمت مراعاة جميع الموارد الأخلاقية في هذه الدراسة، ولم يلحظ مؤلفو المقالة أي تعارض للمنافع. الكشوفات: تحكي نتائج الدراسة عن وجود تأثير ذي معنى للنظرة والمعايير العقلية والأخلاقية والوصفية وكذلك ضبط السلوك المحسوس على نية السلوك الأخلاقي، وفي النهاية فقد تم تأييد تأثير تعديل التعصب الديني. الاستنتاج: يمكن القول طبقاً للمعطيات بأن المجتمع الإيراني رغم كونه مجتمعاً دينياً ولكن المستهلكين يميلون إلى السلوك الأخلاقي بغض النظر عن أي ميول وتعصبات دينية. ويرجع جذور هذه المسألة بالأكثر إلى المعايير الحاكمة على الفرد. وفي هذا المجال فإن دراسة وفهم المعايير الحاكمة لها أهمية كبيرة في تغيير نموذج السلوك الأخلاقي للمستهلكين.   يتم استناد المقالة على الترتيب التالي: Nikraftar T, Hosseini E, Agheli M, Moslemi-Kaviri M. Investigating the Moderating Role of Religiosity in Consumers’ Ethical Behavior: A Case Study of Food Consumers in Isfahan. Journal of Pizhūhish dar dīn va salāmat. 2020;6(3):18-30. https://doi.org/10.22037/jrrh.v6i3.24966 &nbsp