scholarly journals Energy assessment of different cooling technologies in Ti-6Al-4V milling

2021 ◽  
Vol 112 (11-12) ◽  
pp. 3279-3306
Author(s):  
Paolo Albertelli ◽  
Michele Monno
Keyword(s):  
Energy Performance ◽  
Primary Energy ◽  
Cryogenic Cooling ◽  
Model Parameters ◽  
Tribological Behaviour ◽  
Dry Cutting ◽  
Sustainable Solutions ◽  
Energy Assessment ◽  
Energy Models ◽  
Conventional Cooling

AbstractManufacturing craves for more sustainable solutions for machining heat-resistant alloys. In this paper, an assessment of different cooling lubrication approaches for Ti6Al4V milling was carried out. Cryogenic cutting (liquid nitrogen) and conventional cooling (oil-based fluid) were assessed with respect to dry cutting. To study the effects of the main relevant process parameters, proper energy models were developed, validated and then used for comparing the analysed cooling lubrication strategies. The model parameters were identified exploiting data from specifically conceived experiments. The power assessment was carried out considering different perspectives, with a bottom-up approach. Indeed, it was found that cryogenic cooling, thanks to a better tribological behaviour, is less energy demanding (at least 25%) than dry and conventional cutting. If the spindle power is considered, lower saving percentages can be expected. Cryogenic cooling showed its best energy performance (from 3 to 11 times) with respect to conventional cutting if the machine tool perspective is analysed. Considering even the primary energy required for producing the cutting fluids, the assessment showed that cryogenic cooling requires up to 19 times the energy required for conventional cutting.

scholarly journals Experimental investigation of the effects of cryogenic cooling on tool life in Ti6Al4V milling

2021 ◽  
Author(s):  
Paolo Albertelli ◽  
Valerio Mussi ◽  
Matteo Strano ◽  
Michele Monno
Keyword(s):  
Tool Life ◽  
Cutting Speed ◽  
Cryogenic Cooling ◽  
Model Parameters ◽  
Cryogenic Milling ◽  
High Cutting Speed ◽  
Cutting Velocity ◽  
Life Tests ◽  
Conventional Cooling ◽  
Cutting Speeds

AbstractIn this paper, the results of an experimental campaign of cryogenic milling are presented and discussed. For this purpose, a specific experimental setup that allowed to feed the liquid nitrogen LN through the tool nozzles was used. Tool life tests were carried out at different cutting speeds. The tool duration data were collected and used to identify the parameters of the Taylor’s model. Different end-of-life criteria for the tool inserts were even investigated. The achieved results are compared to those obtained using conventional cooling. It was observed that at low cutting velocity, conventional cooling still assures longer tool lives than in cryogenic condition. Since in cryogenic milling the increasing of the cutting velocity is not so detrimental as in conventional cutting, at high cutting speed (from 125 m/min) longer tool durations can be achieved. Statistical analyses on the model parameters were carried out to confirm the presented findings. The analysis of the effect of the cooling approach on the main wear mechanisms was also reported. At low cutting speed, adhesion and chipping phenomena affected the tool duration mainly in cryogenic milling.

scholarly journals Yield Evaluation and Primary Energy Assessment of the Jatropha curcas Oil Extraction Process for Use as a Biofuel in Engines

2021 ◽  
pp. 37-46
Author(s):  
Fredy Torres Mejía ◽  
Juan Alexander Torres Mejía ◽  
Henry Edgardo Maradiaga Galeano ◽  
Claudia López Toro
Keyword(s):  
Jatropha Curcas ◽  
Extraction Process ◽  
Primary Energy ◽  
Oil Extraction ◽  
Raw Material ◽  
Shell Weight ◽  
Jatropha Curcas Oil ◽  
Energy Assessment ◽  
The One ◽  
Jatropha Cake

The aim of this work is to evaluate the performance of the extraction and mechanical filtering of Jatropha curcas oil and to evaluate the primary energy of the raw material resulting from the process, this is a qualitative-quantitative study of transversal order based on measurements and analysis of the process in situ: The following factors were evaluated as factors: weight of oil per seed processed, weight of pressed cake, and measurements in the filtering process, from which a balance of matter of the process used was constructed, and the energy valuation of the oil and pressed cake, energy was used as the response variable, measured in Tons of Oil Equivalent (TEP), Barrels of Oil Equivalent (BEP), and tons of Carbon Dioxide Equivalent (Ton CO2eq). The seed used is Creole, the one existing in the area, the extraction was carried out in a KEK-P0101 press, and a KEK-F0090 filter. The collected seeds were dried and then discarded, the average shell weight is 40% of the total weight of the dry seed, from the oil extraction process a yield of 18.6% was obtained using seed with 5.8% humidity, and from the oil filtering process, when it passed through the filter, no weight loss in kg was obtained; finally, the equivalent primary energy valuation of one ton of oil is 39076. 39 MJTon-1, which is equivalent to 0.94 TEP, 2.90 Ton CO2 eq, and 20.87 BEP; in the same way one ton of Jatropha cake represents 15969.30 MJ, equivalent to 0.38 TEP, 1.18 Ton CO2 eq, and 8. 53 BEP, and the total primary energy between one ton of oil and one ton of Jatropha cake after oil extraction together contain 55045.61 MJTon-1, equivalent to 1.32 TEP, 4.08 Ton CO2 eq, and 29.41 BEP.

scholarly journals Agrotechnical and Energy Performance of Tillage Tools

2021 ◽  
Vol 31 (1) ◽  
pp. 109-126
Author(s):  
Galina G. Parkhomenko ◽  
Igor V. Bozhko ◽  
Sergey I. Kambulov ◽  
Viktor I. Pakhomov
Keyword(s):  
Agricultural Production ◽  
Energy Efficient ◽  
Crop Production ◽  
Crop Residues ◽  
Energy Performance ◽  
Soil Cultivation ◽  
Energy Assessment ◽  
Processing Depth ◽  
Ridge Height ◽  
Wheat Stubble

Introduction. One of the areas of agricultural production is crop production. At the same time, it is necessary to take into account all available possibilities of reducing the energy consumption and labor required for tillage operations that can be achieved by using energy efficient tillage tools. Materials and Methods. In the course of the research, an agrotechnical and energy assessment of the technological process of soil cultivation performed by tillage tools was carried out. The agrotechnical assessment includes identifying the indicators of unevenness of the tillage tool travel depth, soil pulverization, ridging, and the content of erosion threatening particles. As an energy assessment, the indicator of draught created by a tillage tool was taken. The researches were carried out for various configurations of the chisel cultivators with flat and curved hoes, and elements made of polymer. Results. The data of agricultural assessment and draught of chisel cultivators were obtained for various agricultural backgrounds: winter wheat stubble with preliminary disking in one track, winter barley stubble with preliminary disking in one track, and autumn fallow on the background. Discussion and Conclusion. According to the results of the research, it was found that, in terms of quality indicators, the tillage tools meet the agrotechnical requirements for a given processing depth of 25–35 cm. The operation of the chisel equipped with a curved hoe is characterized by the highest presence of clods up to 5 cm (91–96%). The ridge height was 6.8–8.0 cm for all tillage tools. It has been established that the tillage tools are advisable to be uses for anti-erosion soil cultivation. In terms of preserving plant and crop residues, a chisel with a curved hoe providing their content by 9.5–28.6% more than with a polymer of 13.2–14.3%. The chisel with polymer has the smallest draught of 7.6 kN, which is 18.28% lower in comparison with tillage tools equipped with a flat hoe.

scholarly journals Informing the design of courtyard street blocks using solar energy models: a case study of a university campus in Singapore

2021 ◽  
Vol 2042 (1) ◽  
pp. 012050
Author(s):  
Ekaterina Vititneva ◽  
Zhongming Shi ◽  
Pieter Herthogs ◽  
Reinhard König ◽  
Aurel von Richthofen ◽  
...  
Keyword(s):  
Solar Energy ◽  
Urban Form ◽  
Energy Performance ◽  
University Campus ◽  
Quasi Monte Carlo ◽  
Energy Models ◽  
Simulation Based ◽  
Input Variables ◽  
The City

Abstract This study discusses the interplays between urban form and energy performance using a case study in Singapore. We investigate educational urban quarters in the tropical climate of Singapore using simulation-based parametric geometric modelling. Three input variables of urban form were examined: street network orientation, street canyon width, and building depth. In total, 280 scenarios were generated using a quasi-Monte Carlo Saltelli sampler and Grasshopper. For each scenario, the City Energy Analyst, an open-source urban building energy simulation program, calculated solar energy penetration. To assess the variables’ importance, we applied Sobol’ sensitivity analysis. Results suggest that the street width and building depth were the most influential parameters.

Analysis of Energy Sources on Energy Indicators Performance

2016 ◽  
Vol 861 ◽  
pp. 198-205
Author(s):  
Anton Pitonak ◽  
Martin Lopusniak
Keyword(s):  
European Union ◽  
Energy Demand ◽  
Energy Performance ◽  
Primary Energy ◽  
Hot Water ◽  
Energy Class ◽  
The European Union ◽  
Total Consumption ◽  
Minimum Requirements ◽  
Global Indicator

In the members states of the European Union, portion of buildings in the total consumption of energy represents 40%, and their portion in CO2 emissions fluctuates around 35%. The European Union is trying to protect the environment by reducing energy demand and releasing CO2 emissions into the air. Energy performance is the quantity of energy, which is necessary for heating and domestic hot water production, for cooling and ventilation and for lighting. Based on results of energy performance, individual buildings are classified into energy classes A to G. A global indicator (primary energy) is the decisive factor for final evaluation of the building. The new building must meet minimum requirements for energy performance, i.e. it must be classified to energy class A1 since 2016, and to energy class A0 since 2020. The paper analyses effect of the use of different resources of heat in a family house designed according to requirements valid since 2020, and its subsequent classification into an energy class.

scholarly journals A Sustainable Solution for Energy Efficiency in Italian Climatic Contexts

Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2817
Author(s):  
Valeria Annibaldi ◽  
Federica Cucchiella ◽  
Marianna Rotilio
Keyword(s):  
Energy Efficiency ◽  
Life Cycle Cost ◽  
Energy Performance ◽  
Building Envelope ◽  
Reference Scenario ◽  
Life Cycle Cost Analysis ◽  
The European Union ◽  
Optimal Thickness ◽  
Hemp Fiber ◽  
Sustainable Solutions

In the European Union, about 40% of energy consumption and 36% of CO2 emissions come from buildings; therefore, the improvement of their energy performance is a strongly focused issue. In particular, the energy efficiency of the building envelope is a very important element to pay attention to. Many studies have been conducted on this field of research, and the study illustrated in this paper also belongs to this topic. In particular, this article presents a multidisciplinary method to find sustainable solutions for energy efficiency in Italian climatic contexts using the Life Cycle Cost Analysis approach. In detail, this paper defines the reference scenario and then deepens the methodology used to determine the economically optimal thickness of a specific insulating material—hemp fiber—applied to a specific type of wall—uninsulated cavity walls made of hollow bricks, which are very widespread in Italy. The analysis is developed in relation to three different regions—Piedmont, Abruzzo, and Campania. The results show that the economically optimal thickness is different for each region analyzed and demonstrates how energy efficiency strategies must be carefully weighed according to the specific conditions of the site.

scholarly journals Transformation of an Office Building into a Nearly Zero Energy Building (nZEB): Implications for Thermal and Visual Comfort and Energy Performance

Energies ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 895 ◽  
Author(s):  
Ilaria Ballarini ◽  
Giovanna De Luca ◽  
Argun Paragamyan ◽  
Anna Pellegrino ◽  
Vincenzo Corrado
Keyword(s):  
Thermal Comfort ◽  
Energy Savings ◽  
Energy Performance ◽  
Primary Energy ◽  
Building Envelope ◽  
Office Building ◽  
Indoor Environmental Quality ◽  
Visual Comfort ◽  
Zero Energy ◽  
Efficiency Measures

Directive 2010/31/EU promotes the refurbishment of existing buildings to change them into nearly zero-energy buildings (nZEBs). Within this framework, it is of crucial importance to guarantee the best trade-off between energy performance and indoor environmental quality (IEQ). The implications of a global refurbishment scenario on thermal and visual comfort are assessed in this paper pertaining to an existing office building. The retrofit actions applied to achieve the nZEB target consist of a combination of envelope and technical building systems refurbishment measures, involving both HVAC and lighting. Energy and comfort calculations were carried out through dynamic simulation using Energy Plus and DIVA, for the thermal and visual performance assessments, respectively. The results point out that energy retrofit actions on the building envelope would lead to significant improvements in the thermal performance, regarding both energy savings (−37% of the annual primary energy for heating) and thermal comfort. However, a daylighting reduction would occur with a consequent higher electricity demand for lighting (36%). The research presents a detailed approach applicable to further analyses aimed at optimizing the energy efficiency measures in order to reduce the imbalance between visual and thermal comfort and to ensure the best performance in both domains.

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