Designing a Cold Plate Used in Rapid Freeze Prototyping Technology

2014 ◽  
Vol 1036 ◽  
pp. 648-651
Author(s):  
Alevandru Savin ◽  
Alexandru Floca ◽  
Mihai Trifănescu ◽  
Nicolae Ionescu ◽  
Aurelian Vişan

The rapid prototyping with ice is a new manufacturing technology that can generate three-dimensional objects from ice by depositing and rapidly freezing water layer by layer. In order to freeze the water droplets, the plate must meet certain conditions, among those it is worth to be mentioned, the surface temperature, which should not surpass 0°C. The equipment presented in the paper is a part of rapid freeze prototyping equipment, designed and built by the authors. The authors analysed various freezing systems and they discovered that the classical cooling systems are not appropriate to be used in rapid freeze prototyping technology. The unique solution is the utilisation of thermoelectric cells, generic named as Peltier cells. The modern technology can be used in obtaining Peltier cells, with a high degree of reliability, electrical consumption and yield. This can be successfully used as heat pumps in industry. The author developed an original system that permitted to implement the Peltier cells. The cold plate was designed by using CAD software. In addition, the cold plate was produced and tested. The equipment obtained, has a greater power in comparison with the classical ones, even if it has smaller dimensions. The electrical power supply has to be well filtered in order to generate a higher efficiency. Through the main advantages of the Peltier cells can be mentioned: no maintenance have to be performed as this type of cells have no moving parts, thus having a major advantage; no CFC or other consumables parts have to be used, thus proving to be more economical than other systems; the heat regulation can be performed easier compared with the classical systems offering a better control and precision; it can be used in severe environments where conventional cooling systems can fail, being successfully used in the presence of liquid nitrogen; it can perform in various positions and is reversible similar to heat pumps. The main drawback of this system is that it uses a great amount of electrical energy, consequently can have a low yield.

2003 ◽  
Vol 125 (4) ◽  
pp. 824-834 ◽  
Author(s):  
Guanghua Sui ◽  
Ming C. Leu

Rapid Freeze Prototyping (RFP) builds ice parts by depositing and freezing water in a layer-by-layer manner. This paper presents a one-dimensional transient heat transfer model for a thin ice wall built by the RFP process. Closed-form solutions for temperatures of the ice wall during solidification of a layer of water are derived, which can be used to estimate the solidification time. Natural cooling of the ice wall after solidification of a water layer is also studied. The analytical solutions of heating and cooling of the ice wall agree well with both numerical and experimental results.


Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2851 ◽  
Author(s):  
Kenneth Leerbeck ◽  
Peder Bacher ◽  
Rune Grønborg Junker ◽  
Anna Tveit ◽  
Olivier Corradi ◽  
...  

An optimized heat pump control for building heating was developed for minimizing CO 2 emissions from related electrical power generation. The control is using weather and CO 2 emission forecasts as inputs to a Model Predictive Control (MPC)—a multivariate control algorithm using a dynamic process model, constraints and a cost function to be minimized. In a simulation study, the control was applied using weather and power grid conditions during a full-year period in 2017–2018 for the power bidding zone DK2 (East, Denmark). Two scenarios were studied; one with a family house and one with an office building. The buildings were dimensioned based on standards and building codes/regulations. The main results are measured as the CO 2 emission savings relative to a classical thermostatic control. Note that this only measures the gain achieved using the MPC control, that is, the energy flexibility, not the absolute savings. The results show that around 16% of savings could have been achieved during the period in well-insulated new buildings with floor heating. Further, a sensitivity analysis was carried out to evaluate the effect of various building properties, for example, level of insulation and thermal capacity. Danish building codes from 1977 and forward were used as benchmarks for insulation levels. It was shown that both insulation and thermal mass influence the achievable flexibility savings, especially for floor heating. Buildings that comply with building codes later than 1979 could provide flexibility emission savings of around 10%, while buildings that comply with earlier codes provided savings in the range of 0–5% depending on the heating system and thermal mass.


2015 ◽  
Vol 787 ◽  
pp. 782-786 ◽  
Author(s):  
R. Prakash ◽  
D. Christopher ◽  
K. Kumarrathinam

The prime objective of this paper is to present the details of a thermoelectric waste heat energy recovery system for automobiles, more specifically, the surface heat available in the silencer. The key is to directly convert the surface heat energy from automotive waste heat to electrical energy using a thermoelectric generator, which is then regulated by a DC–DC Cuk converter to charge a battery using maximum power point tracking. Hence, the electrical power stored in the battery can be maximized. Also the other face of the TEG will remain cold. Hence the skin burn out accidents can be avoided. The experimental results demonstrate that the proposed system can work well under different working conditions, and is promising for automotive industry.


2021 ◽  
Vol 17 (2) ◽  
pp. 204-211
Author(s):  
Raheel Jawad ◽  
Rawaa Jawad ◽  
Zahraa Salman

In the present-day decade, the world has regarded an expansion in the use of non-linear loads. These a lot draw harmonic non-sinusoidal currents and voltages in the connection factor with the utility and distribute them with the useful resource of the overall performance of it. The propagation of these currents and voltages into the grids have an effect on the electricity constructions in addition to the one of various client equipment. As a result, the electrical strength notable has come to be critical trouble for each client and distributor of electrical power. Active electrical electricity filters have been proposed as environment splendid gear for electrical power pinnacle notch enchantment and reactive electrical strength compensation. Active Power Filters (APFs) have Flipped out to be a possible wish in mitigating the harmonics and reactive electrical electricity compensation in single-phase and three-phase AC electrical energy networks with Non-Linear Loads (NLLs). Conventionally, this paper applied Ant Colony Algorithm(ACO) for tuning PI and reduce Total Harmonic Distortion (THD). The result show reduces THD at 2.33%.


2017 ◽  
Vol 79 (5-2) ◽  
Author(s):  
Zul Hasrizal Bohari ◽  
Nur Asyhikin Azhari ◽  
Nuraina Nasuha Ab Rahman ◽  
Mohamad Faizal Baharom ◽  
Mohd Hafiz Jali ◽  
...  

Energy trending lately shown the need of new possible renewable energy. This paper studies about the capability and capacity generating of electricity by using Bio-electricity-Microbial Fuel Cell (Bio-MFC). Bio-MFC is the device that converts chemical energy to electrical energy by using microbes that exist in the sewage water. The energy contained in organic matter can be converted into useful electrical power. MFC can be operated by microbes that transfer electrons from anode to cathode for generating electricity. There are two major goals in this study. The first goal is to determine the performance characteristics of MFCs in this application. Specifically we investigate the relationship between the percentages of organic matter in a sample results in higher electricity production of MFCs power by that sample. As a result, the sewage (wastewater) chosen in the second series experiment because the sewage (wastewater) also produced the highest percentage of organic matter which is around 10%. Due to these, the higher percentage of organic matter corresponds to higher electricity production. The second goal is to determine the condition under which MFC work most efficiently to generating electricity. After get the best result of the combination for the electrode, which is combination of zinc and copper (900mV),the third series of experiments was coducted, that show the independent variable was in the ambient temperature. The reasons of these observations will be explained throughout the paper. The study proved that the electricity production of MFC can be increased by selecting the right condition of sample type, temperature and type of electrode. 


2017 ◽  
Vol 77 (2) ◽  
pp. 364-374 ◽  
Author(s):  
Azize Ayol ◽  
Ozgun Tezer ◽  
Alim Gurgen

Abstract Sludges produced in biological wastewater treatment plants have rich organic materials in their characteristics. Recent research studies have focused on the energy recovery from sludge due to its high organic content. The gasification process is a thermal conversion technology transforming the chemical energy contained in a solid fuel into thermal energy and electricity. The produced syngas as a mixture of CO, CH4, H2 and other gases can be used to generate electrical energy. The gasification of yeast industry sludge has been experimentally evaluated in a pilot scale downdraft-type gasifier as a route towards the energy recovery. The gasifier has 20 kg biomass/h fuel capacity. During gasification, the temperature achieved was more than 1,000°C in the gasifier, and then the syngas was transferred to the gas engine to yield the electricity. A load was connected to the grid box and approximately 1 kWh electrical power generation for 1 kg dry sludge was determined. The characteristics of residuals – ash, glassy material – were also analyzed. It was found that most of the heavy metals were fixed in the glassy material. Experimental results showed that the yeast industry sludge was an appropriate material for gasification studies and remarkable energy recovery was obtained in terms of power production by using syngas.


Author(s):  
Emanuele Frontoni ◽  
Adriano Mancini ◽  
Primo Zingaretti ◽  
Andrea Gatto

Advanced technical developments have increased the efficiency of devices in capturing trace amounts of energy from the environment (such as from human movements) and transforming them into electrical energy (e.g., to instantly charge mobile devices). In addition, advancements in microprocessor technology have increased power efficiency, effectively reducing power consumption requirements. In combination, these developments have sparked interest in the engineering community to develop more and more applications that utilize energy harvesting for power. The approach here described aims to designing and manufacturing an innovative easy-to-use and general-purpose device for energy harvesting in general purpose shoes. The novelty of this device is the integration of polymer and ceramic piezomaterials accomplished by injection molding. In this spirit, this paper examines different devices that can be built into a shoe, (where excess energy is readily harvested) and used for generating electrical power while walking. A Main purpose is the development of an indoor localization system embedded in shoes that periodically broadcasts a digital RFID as the bearer walks. Results are encouraging and real life test are conducted on the first series of prototypes.


2018 ◽  
Vol 67 ◽  
pp. 04011
Author(s):  
Sunaryo Sunaryo ◽  
Adri Wirawan Ramadhani

Indonesia has more than 17,000 islands and has plenty of beautiful beaches and underwater spots which have great potential for maritime tourism. Tourism was ranked 3rd on Indonesia's foreign income and plays an important role for the country’s ecomony. Despite having potential advantages, the government has not yet maximized its efforts to develop the attractiveness of its maritime tourism. Beside the beautiful spots Indonesia is also blessed with all year long sun shine, which could be tapped as renewable and green energy as substitution to fossil fuel. Refer to these great advantages of natural resources the research was aimed to support the government’s program in developing its maritime tourism and to promote the use of green and renewable energy by designing a solar-powered tourism recreational boat which has 12 meters of length. The paper is focused on the design of solar energy and its electrical system, which includes conversion of solar energy to electrical energy and store it in the battery, the required electrical power is also predicted based on the appliances and equipment installed in the boat, the optimum attachment of solar panels on the boat structure is also calculated. All the methods and information we use are obtained from literature study, discussion with experts, and surveys to Jagur as solar-powered electric boat from Universitas Indonesia.


Author(s):  
Putu Dian Paramitha Dewi ◽  
I Wayan Suarna ◽  
I Wayan Budiarsa Suyasa

Waste is one source of greenhouse gas emissions (GHG) that has methane gas form which caused an early multi-dimensional, massive and complex problems. The rapid increase of garbage volume entering landfill, annually result a high garbage dumps in the Suwung Landfill area. It should have been considered a handing solution for example by converting the methane gas content in the waste into a useful value added product. The objective of this research is determining the amount of electrical energy that can be produced through methane gas emission at Suwung Landfill. The characteristic and composition of waste could give effect to the formation of methane emissions. The research on the composition and characteristic of waste were done by sorting 1 m3 of garbage sample from new garbage entering landfill. Garbage is divided based on the source of DLHK waste, market waste, and private waste. The volume of waste that went to Suwung Landfill in 2016 calculated 1.296.438 m3 which was dominated by organic waste (78,1%). The density of the waste that went into Suwung Landfill, based on the research's results, amounted to 135,09 kg / m3, there fore could be assumed that the weight of waste that went to Suwung Landfill in 2016 was 175.135,81 tons. Based on these data, the number of 136.785,13 tons of waste, which was organic waste, could increase the concentration of greenhouse gases in the atmosphere if this situation does not manage properly. Gravimeter method is using for measures the dry matter content value of waste. From the measurement, the results obtained the waste components that have the highest dry matter content is from rubber and leather garbage (76,52%) while the lowest dry matter is food waste (19,13%). By using calculations based on IPCC 2006, it was found that the amount of methane emissions could be generated by the waste at the Suwung Landfill in 2016, amounted to 3.535,06 tons. Based on the energy equivalence table, the electrical power that is generated from the potential methane emissions at the Suwung Landfill is 6,66 MW. Keywords: waste composition, waste characteristics, methane emissions, ipcc2006, electrical power.


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