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This study illustrates a factory's production efficiency by demonstrating its energy efficiency in the dairy milk industry. Determining the thermal energy to save energy enhances the profitability of the factory. The aim of this study is to conduct a thermal energy and production analysis of a dairy milk factory based on annual production. This study intends to make the conclusions more realistic by using production and energy data dependability analysis. The overall power consumption for the thermal and electric energy processes was found to be as 180,520 [W]. The target-specific energy consumption value was computed for Case 1 as 6,352.14 [MJ/t], for Case 2 as 5,898.67 [MJ/t], and for Case 3 as 5,445.21 [MJ/t]. The annual thermal (steam boiler) and electrical energy expenditures were obtained, with 315.87 [kW] of thermal (steam) energy and 80.98 [kW] of electrical energy. The total thermal and electrical energy reached 396.85 [kW]. Despite the factory's expenditure on thermal and electrical energy, the energy efficiency was determined to be as 45.5%. The input energy was obtained to be 374.24 [kW] in Case 1, 356.33 [kW] in Case 2, and 342.08 [kW] in Case 3. The energy efficiency was calculated as 48.2 [%] for Case 1, 50.7 [%] for Case 2, and 52.8 [%] for Case 3. This study, which is expected to inspire future research, is also likely to assist livestock and agriculture in the energy field. The novelty of this study is that optimizing product efficiency and energy consumption in the production of milk and dairy products positively increases the energy efficiency of factories. [ABSTRACT FROM AUTHOR]

The rock deformation and failure characteristics and mechanisms are very important for stability evaluation and hazard control in rock engineering. The process of rock deformation and failure is often accompanied by temperature changes. It is of great significance to study the characteristics and mechanism of temperature variation in rock under deformation and fracturing for a better understanding of rock failure and to obtain some probable precursor information for guiding the prediction of the mechanical behavior of rock. However, most of the studies are based on observations in the field and laboratory tests, while it is still required to develop an effective method for modeling and calculating the temperature variation of rock during the deformation and failure processes. In this paper, a particle flow modeling method based on energy analyses is proposed for simulating the temperature variation of rocks, considering four temperature effects, including the thermoelastic effect, friction effect, damping effect, and heat conduction effect. The four effects are analyzed, and the theoretical equations have been provided. On this basis, the numerical model is built and calibrated according to the laboratory uniaxial compressive experiment on a marble specimen, and a comparison study has been conducted between the laboratory and numerical experiment results. It is found that the numerical model can well simulate the average value and distribution of the temperature variation of rock specimens, so this method can be applied for studying the mechanism of temperature variation more comprehensively during the whole process of rock deformation and fracturing compared with the continuous modeling methods. With this method, it is shown that the temperature change has three different stages with different characteristics during the uniaxial compression experiments. In the different stages, the different effects play different roles in temperature variation, and stress distribution and crack propagation have obvious influences on the local distribution of temperature. Further investigations have also been conducted in a series of sensitive analyses on the influences of four factors, including the thermal conductivity, friction coefficient, thermal expansion coefficient, and particle size ratio. The results show that they have different influences on the thermal and mechanical behaviors of the rock specimens during the deformation and failure process, while the thermal expansion coefficient and the particle size ratio have more significant impacts than the other two factors. These findings increase our knowledge on the characteristics and mechanism of temperature variation in rock during the deformation and fracturing process, and the proposed modeling method can be used in more studies for deformation and fracturing analyses in rock experiments and engineering. [ABSTRACT FROM AUTHOR]

The rock deformation and failure characteristics and mechanisms are very important for stability evaluation and hazard control in rock engineering. The process of rock deformation and failure is often accompanied by temperature changes. It is of great significance to study the characteristics and mechanism of temperature variation in rock under deformation and fracturing for a better understanding of rock failure and to obtain some probable precursor information for guiding the prediction of the mechanical behavior of rock. However, most of the studies are based on observations in the field and laboratory tests, while it is still required to develop an effective method for modeling and calculating the temperature variation of rock during the deformation and failure processes. In this paper, a particle flow modeling method based on energy analyses is proposed for simulating the temperature variation of rocks, considering four temperature effects, including the thermoelastic effect, friction effect, damping effect, and heat conduction effect. The four effects are analyzed, and the theoretical equations have been provided. On this basis, the numerical model is built and calibrated according to the laboratory uniaxial compressive experiment on a marble specimen, and a comparison study has been conducted between the laboratory and numerical experiment results. It is found that the numerical model can well simulate the average value and distribution of the temperature variation of rock specimens, so this method can be applied for studying the mechanism of temperature variation more comprehensively during the whole process of rock deformation and fracturing compared with the continuous modeling methods. With this method, it is shown that the temperature change has three different stages with different characteristics during the uniaxial compression experiments. In the different stages, the different effects play different roles in temperature variation, and stress distribution and crack propagation have obvious influences on the local distribution of temperature. Further investigations have also been conducted in a series of sensitive analyses on the influences of four factors, including the thermal conductivity, friction coefficient, thermal expansion coefficient, and particle size ratio. The results show that they have different influences on the thermal and mechanical behaviors of the rock specimens during the deformation and failure process, while the thermal expansion coefficient and the particle size ratio have more significant impacts than the other two factors. These findings increase our knowledge on the characteristics and mechanism of temperature variation in rock during the deformation and fracturing process, and the proposed modeling method can be used in more studies for deformation and fracturing analyses in rock experiments and engineering.

Effective use of industrial heat waste at low and medium temperatures is seen as one of the solutions that can be used to increase energy efficiency and reduce the problem of environmental pollution. Within the understanding of this framework, the organic Rankine cycle (ORC) maintains to gain attention and further development by researchers and/or manufacturers due to its technical and economical use and credibility. This study presents thermodynamic and economic analyses on ue gas assisted organic Rankine cycle (FGA-ORC) based on both concepts of energy and exergy. The heat source for the FGA-ORC system is the exhaust ue gas of the stenter machine, which is highly used in the textile finishing process. In this study, an optimization investigation has been carried out for a cycle architecture, which converts thermal energy into electrical and/or mechanical energy. The effect of the working parameters of the stenter frame on the performance indicators such as efficiency, performance ratio and economic profit was parametrically analyzed, and the net-work, exergy destruction and efficiency values were determined. The results of these analyses showed that the optimum working parameters of the FGA-ORC system were P1=1311 kPa, Pmid=970 kPa, Tgas,in=140°C, PC=35%, To=25°C for an exergetic efficiency of 68.86%. [ABSTRACT FROM AUTHOR]

Hydrogen is the most abundant element in the world and produces only water vapor as a result of chemical reaction that occurred in fuel cells. Therefore, fuel cell electric vehicles, which use hydrogen as fuel, continue its growing trend in the sector. In this study, an energy distribution comparison is carried out between fuel cell electric vehicle and fuel cell hybrid electric vehicle. Hybridization of fuel cell electric vehicle is designed by equipped a traction battery (15 kW). Modeled vehicles were prepared under AVL Cruise program with similar chassis and same fuel cell stacks for regular determining process. Numerical analyses were presented and graphed with instantaneous results in terms of sankey diagrams with a comparison task. WLTP driving cycle is selected for both vehicles and energy input/output values given with detailed analyses. The average consumption results of electric and hydrogen usage is found out as 4.07 kWh and 1.125 kg/100 km respectively for fuel cell electric vehicle. On the other hand, fuel cell hybrid electric vehicle's average consumption results figured out as 3.701 kWh for electric and 0.701 kg/100 km for hydrogen consumption. As a result of this study, fuel cell hybrid electric vehicle was obtained better results rather than fuel cell electric vehicle according to energy and hydrogen consumption with 8% and 32%, respectively. • Fuel Cell Electric Vehicle and its hybrid version were compared in energy task. • FCEV and FCHEV energy distribution was illustrated as sankey diagrams. • Hydrogen and electrical consumptions were discussed detailed. • The importance of AVL Cruise and WLTP driving cycle were expressed deeply. • FCHEV has more preferable results than FCEV, for this study's parameters. [ABSTRACT FROM AUTHOR]

In this study thermodynamic parameter and energy consumption in drying of two plant dill and mint in three bed drying including fix, semi fix and fluid with using a hot air drying was investigated. Experimental was conducted in three bed drying including fix, semi fix and fluid and four levels temperature (30, 40, 50 and 60 °C). Maximum energy consumption in dill drying at 40 °C and fluid bed to be 16.41 MJ and minimum energy consumption at 30 °C and fix bed to be 2.77 MJ. Also minimum energy consumption in mint drying at 60 °C and fix bed to be 3.64 MJ and maximum energy consumption at 40 °C and fluid bed to be 28.65 MJ. The highest energy, drying and thermal efficiency for both mint and dill was achieved at 60 °C on the fixed bed, whereas the lowest efficiency was at 40 °C and on the fluidized bed. Also the highest power and specific heat consumption for both mint and dill was achieved at 40 °C on the fluid bed, whereas the lowest efficiency was at 30 °C and on the fluidized bed.

One of the main benefits of Building Information Modelling is the capability of improving the decision-making process thanks performing what-if tests on digital twins of the building to be realized. Pairing BIM models to Building Energy Models allows designers to determine in advance the energy consumption of the building, improving sustainability of the construction. The challenge is to consider as many elements involved in the energy balance as possible and shuffling their parameters within a certain range. In this work, the automatic creation of a relevant set of design options to be analyzed for searching the optimum has been carried out. Firstly, the usual workflow that would be applied manually has been automatically followed by running scripts and codes, depending just on the initial setup given by the user. Although the procedure is very resource consuming, the main advancement relies in the reduction of the manual intervention and the possibility of creating large datasets of design options, avoiding gross errors. Secondly, Artificial Neural Networks and Transfer Learning techniques are applied to speed up the process of dataset creation. With such approach, the same dataset has been created, with about 30% of initial data and without significant loss of accuracy.

In this study, the plant node was dried in an oven (40, 50 and 60 °C), shade and temperature-controlled microwave (40, 50 and 60 °C) methods. Statistically (p<0.05), the values closest to the color values of fresh grass were determined in an oven at 40 °C drying temperature. Effective diffusion values varied between 8.85×10 -8 -5.65×10 -6  m 2  s -1 . While the activation energy was 61.28 kJ mol -1 in the oven, it was calculated as 85.24 kJ mol -1 in the temperature-controlled microwave. Drying data was best estimated in the Midilli-Küçük (R 2 0.9998) model oven at 50 °C. The highest SMER value was calculated as 0.0098 kg kWh -1 in the temperature-controlled microwave drying method. The lowest SEC value in the temperature-controlled microwave was determined as 24.03 kWh kg -1 . It was determined that enthalpy values varied between -2484.66/-2623.38 kJ mol -1 , entropy values between -162.04/-122.65 J mol -1 and Gibbs free energy values between 453335.22-362581.40 kJ mol -1 . Drying rate values were calculated in the range of 0.0127-0.9820 g moisture g dry matter -1 in the temperature-controlled microwave, 0.0003-0.0762 g dry matter -1 in the oven, and 0.001-0.0058 g moisture g dry moisture matter -1 in the shade. Phenolic content 6957.79 μg GAE g -1 fw - 48322.27 μg GAE g -1 dw, flavonoid content 3806.67 mg KE L -1 fw - 22200.00 mg KE L -1 dw and antioxidant capacity 43.35 μmol TE g -1 fw - 323.47 μmol TE g -1 dw. The highest chlorophyll values were obtained from samples dried in an oven at 40 °C. According to the findings, it is recommended to dry the knotweed (Polygonum cognatum Meissn.) plant in a temperature-controlled microwave oven at low temperatures. In this study, in terms of drying kinetics and energy parameters, a temperature-controlled microwave dryer of 60 °C is recommended, while in terms of quality characteristics, oven 40 °C and shade methods are recommended., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Abstract: Heat pump systems are recognized to be outstanding heating, cooling and water heating systems. They provide high levels of comfort as well as offering significant reductions in electrical energy use. In addition, they have very low levels of maintenance requirements and are environmentally attractive. The purpose of this study is to evaluate the experimentally performance and energy analysis of vertical ground-source heat pump (GSHP) for winter climatic condition of Erzurum, Turkey. For this aim, an experimental analysis was performed on GSHP system made up in the Energy Laboratory in the campus of Ataturk University. The experimental apparatus consisted of a ground heat exchanger, the depth of which was 53m, a liquid-to-liquid vapor compression heat pump, water circulating pumps and other measurement and control equipments. Tests were performed under laboratory conditions for space heating, in which experimental results were obtained during January–May within the heating season of 2007. The experimentally obtained results were used to calculate the heat pump coefficient of performance (COP) and the system performance (COPs). The COP and COPs were found to be in the range of 2.43–3.55 and 2.07–3.04, respectively. This study also shows that the system proposed could be used for residential heating in the province of Erzurum which is one of the coldest climate region of Turkey. [Copyright &y& Elsevier]

Abstract: The present study aims to compare three different types of designed flat-plate solar air heaters, two having fins (Type II and Type III) and the other without fins (Type I), one of the heater with a fin had single glass cover (Type III) and the others had double glass covers (Type I and Type II). The energy and exergy output rates of the solar air heaters were evaluated for various air flow rates (25, 50 and 100m3/m2 h), tilt angle (0°, 15° and 30°) and temperature conditions versus time. Based on the energy and exergy output rates, heater with double glass covers and fins (Type II) is more effective and the difference between the input and output air temperature is higher than of the others. Besides, it is found that the circulation time of air inside the heater played a role more important than of the number of transparent sheet. Lower air flow rates should be preferred in the applications of which temperature differences is more important. [Copyright &y& Elsevier]

Abstract: This paper presents a novel approach to temperature probability density distribution and function. Probability density functions and frequency are successfully used in wind speed and solar energy analyses in literature. This study applies these data to temperature data analysis. The present model is developed using the indoor and outdoor temperature as a parameter. Outdoor temperature distribution is crucial for the calculation of monthly and total degree-hour. In this paper, using past weather data, the outdoor temperature probability density functions are modeled for four cities in different regions in Turkey via a new computer program. The main advantage of this approach is to allow us to determine heating and cooling loads with respect to different indoor and outdoor temperatures. [Copyright &y& Elsevier]

One of the main benefits of Building Information Modelling is the capability of improving the decision-making process thanks performing what-if tests on digital twins of the building to be realized. Pairing BIM models to Building Energy Models allows designers to determine in advance the energy consumption of the building, improving sustainability of the construction. The challenge is to consider as many elements involved in the energy balance as possible and shuffling their parameters within a certain range. In this work, the automatic creation of a relevant set of design options to be analyzed for searching the optimum has been carried out. Firstly, the usual workflow that would be applied manually has been automatically followed by running scripts and codes, depending just on the initial setup given by the user. Although the procedure is very resource consuming, the main advancement relies in the reduction of the manual intervention and the possibility of creating large datasets of design options, avoiding gross errors. Secondly, Artificial Neural Networks and Transfer Learning techniques are applied to speed up the process of dataset creation. With such approach, the same dataset has been created, with about 30% of initial data and without significant loss of accuracy. [ABSTRACT FROM AUTHOR]

Evaluation of energy performance of a proposed lightweight concrete, a structural component, in a building application is a novel approach and significant attempt for the future of energy-efficient buildings. Buildings are one of the largest energy consumers in the world. Thermal protection in a building is the most effective way for energy saving. Many stimulatory measures for the spreading of energy savings technologies have been recently applied into the building sectors. In this study, an investigation was carried out based upon an experimental investigation to decide the thermal properties of the lightweight concrete with different ratios of vermiculite. Moreover, analytical simulation to evaluate the energy consumption in a real building application was carried out for various fuels and different climate regions of Turkey. The results show that the most significant reduction in the total heat need occurs in the 4th region, with about 5.6 kWh/m2-year for a thickness of 0.2 m. An energy-saving of 7.5% can be achieved in the 1st region. The proposed concrete can provide a significant reduction in energy consumption and can reduce the carbon emission related to the lower energy need of the buildings. The annual saving can increase to 0.61 $/m2 for LPG in the 4th region. The payback period varies between 1.4 years and 9 years, depending on the fuel. Many OECD countries having a high population pay higher prices for electricity and natural gas compared to Turkey. It means that such an energy-efficient material can save more price due to their higher fuel cost. • Vermiculite reinforced lightweight concrete was used for the building applications. • Energy and cost analysis were made for different climate regions and fuels. • The concretes in the building application can provide a promising advancement. • Annual energy savings of about 7.5% can be achieved for a concrete thickness of 0.25 m. [ABSTRACT FROM AUTHOR]

• A 300 MW coal-fired power plant with sodium-based CO 2 capture system was simulated. • Process integration reduced the gross efficiency penalty from 15.5% to 8.55%. • A new system combined with two power plants and heat network was proposed. • CO 2 capture energy consumption was reduced to 1.08 GJ/tCO 2 by heat recovery. Post-combustion CO 2 capture using sodium-based solid sorbents is viewed as a promising technology owing to its advantages of low cost, easy accessibility, and low desorption temperature. It is necessary to evaluate the efficiency penalty of coal-fired power plants (CFPPs) using sodium-based solid sorbents prior to industrial applications. In this study, a typical 300 MW CFPP, coupled with a sodium-based CO 2 capture system, was established in Aspen Plus. The simulation results demonstrate that the gross efficiency penalty was 15.5% as a result of this process. The energy consumption for the CO 2 capture process was 7.23 GJ/tCO 2 without any heat recovery; substantially higher than that of typical Monoethanolamine (MEA)-based CCS technologies, which is in the range of 3.8 to 4.2 GJ/tCO 2. By recovering the heat of the outlet gas and sorbents from the desorption reactor, the energy consumption was reduced to 4.04 GJ/tCO 2 , with a gross efficiency penalty of 8.55%. To recover low-level heat from the sorption reactor, an economical system was proposed, consisting of a CFPP with CO 2 capture and a cogeneration unit with an absorption heat pump. The energy consumption was further reduced to 1.08 GJ/tCO 2 , and the net efficiency penalty of this economical system was 11.99%. This method may provide significant economic and application prospects for sodium-based CO 2 capture technology. [ABSTRACT FROM AUTHOR]