ENERGY SAVING COMPLEX OF MODULAR TIPE FOR SPACECRAFT POWER SUPPLICTS FULL-SCALE ELECTRICAL TESTS

2020 ◽  
Author(s):  
E.A. Mizrakh ◽  
◽  
D.K. Lobanov ◽  
D.N. Poymanov ◽  
S.B. Tkachev ◽  
...  
Keyword(s):  
Energy Saving ◽  
Full Scale

Numerical Investigation of Energy Saving Device Effects on Ships With Propeller-Hull Interactions

2018 ◽  
Author(s):  
Ravi Chaithanya Mysa ◽  
Le Quang Tuyen ◽  
Ma Shengwei ◽  
Vinh-Tan Nguyen
Keyword(s):  
Energy Saving ◽  
Full Scale ◽  
Navier Stokes ◽  
Detached Eddy Simulation ◽  
Propulsion Efficiency ◽  
Operational Conditions ◽  
Ship Resistance ◽  
The Past ◽  
Eddy Simulation ◽  
Flow Features

Energy saving devices (ESD) such as propeller ducts, pre-swirl stators, pre-nozzles, etc have been explored as a more economic and reliable approach to reduce energy consumption for both in-operation and newly design ships over the past decades. Those energy saving devices work in the principle of reducing ship resistance and improving propulsion efficiency as well as hull-propeller interactions. Potential saving from various types of ESD have been reported in literature from the range of 3–9% [1] for propulsion efficiency dependent on different measures. Deployment of those devices on actual full-scale ships has been limited over the past years. One of the key obstacles in application of ESD is the lack of confidence in measuring its efficiency on full-scale ships in actual operational conditions. Advances in computational fluid dynamics (CFD) has provided an alternative approach from model scale test to better understand uncertainties in prediction of ESD efficiency in full-scale ship operations [Shin et al, 2013]. In this work a high fidelity CFD model is presented for investigation effects of pre-nozzles on propulsion efficiency and ship resistance. The model is based on the Reynolds Average Navier-Stokes (RANS) solver with different turbulent models including a hybrid detached eddy simulation (DES) approach for predictions of complex near body flow features as well as in the wake regions from hull and propeller. The model is validated with model test for both towing and self-propulsion conditions. Finally a study of pre-nozzle effects on propeller efficiency as well as hull-propeller interaction is presented and compared with available experimental data (Tokyo 2015 Workshop). The current work constitutes a fundamental approach towards designing more efficient ESD for a specific hull form and propeller.

scholarly journals Full-scale Studies of Improving Energy Performance by Renovating Historic Swedish Timber Buildings with Hemp-lime

2019 ◽  
Vol 9 (12) ◽  
pp. 2484 ◽  
Author(s):  
Paulien Strandberg-de Bruijn ◽  
Anna Donarelli ◽  
Kristin Balksten
Keyword(s):  
Energy Saving ◽  
Material Properties ◽  
Energy Use ◽  
Building Design ◽  
Energy Performance ◽  
Full Scale ◽  
Space Heating ◽  
Original Material ◽  
Insulation Material ◽  
Thermal Transmittance

With an increased focus on reducing greenhouse gas emissions, energy saving is of great importance in all sectors of society. EU directives set targets for member states to reduce energy use in buildings. Energy saving in historic buildings requires special measures, balancing energy-saving renovations against the preservation of heritage values. Traditional constructions are open to vapor diffusion and generally work differently from modern constructions. Modern materials in traditional constructions sometimes damages the original material as they are usually diffusion-tight. The aim of this study was to investigate whether hemp-lime could be used as an insulation material to improve the energy efficiency of historic timber building envelopes with a rendered façade in Sweden. The objective was to determine the actual energy savings for space heating. An additional objective was to determine the actual thermal transmittance and to study thermal buffering through in-situ measurements in a full-scale wall renovated with hemp-lime. Two full-scale wall sections were constructed at the Energy and Building Design laboratory at Lund University: A traditional post-and-plank wall with a lime render (80 mm), and a post-and-plank wall with a hemp-lime render (90 mm). Energy use for space heating was monitored continuously over a period of one year. The wall with a hemp-lime render required 33% less energy for space heating than the traditional post-and-plank wall with a lime render. This was accomplished without changing the framework, appearance or material in the render and without drastically changing the hygric properties of the façade. From the gathered data, the thermal transmittance (U-values) for both walls was calculated using two different methods, one based on material properties and the other based on energy use data. For both walls, thermal transmittance based on actual energy use data during the heating period was lower than what was expected from their material properties. This indicates that more material properties than thermal conductivity and material thickness need to be taken into account when performing energy use calculations. With hemp-lime, a renovation can be accomplished without damaging the timber structure and wooden slats, and it can be done with local traditional materials and building methods with no difference in appearance to a traditional lime render. This allows for heritage values to be preserved, while also allowing the building to comply with modern standards and with increased thermal comfort and reduced energy use.

Study on movable light-shelf system with location-awareness technology for lighting energy saving

2016 ◽  
Vol 26 (6) ◽  
pp. 796-812 ◽  
Author(s):  
Heangwoo Lee ◽  
Sang-hoon Gim ◽  
Janghoo Seo ◽  
Yongseong Kim
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Energy Savings ◽  
Full Scale ◽  
Location Awareness ◽  
Energy Saving Potential ◽  
Recent Increase ◽  
Lighting Energy ◽  
External Conditions ◽  
Incoming Light

Various ongoing studies regard light-shelves as one solution to the recent increase in lighting energy consumption. However, in previous light-shelf systems, the direction of incoming light was determined by external conditions, thereby limiting the efficiency of lighting energy saving. The purpose of the present study was to develop a movable light-shelf system with location-awareness technology and verify its performance. In this study, a full-scale testbed was established in order to test the proposed movable light-shelf system with location awareness as well as to verify its energy saving potential. The results were analysed and compared with the performances of previous fixed (Case 1) and movable (Case 2) light-shelf systems without location-awareness technology. The obtained results were as follows. (1) The proposed light-shelf system can respond to external conditions and to the location of the occupant by means of the control axis of the light-shelf module angle through modulation between the control axis of the angle of the previous light-shelf and the reflector of the light-shelf. (2) The proposed light-shelf system provides 90.0% and 86.6%/91.0% energy savings in comparison to Case 1 and Case 2, respectively.

An overset RaNS prediction and validation of full scale stern wake for 1,600TEU container ship and 63,000 DWT bulk carrier with an energy saving device

2020 ◽  
Vol 105 ◽  
pp. 102417
Author(s):  
Nobuaki Sakamoto ◽  
Hiroshi Kobayashi ◽  
Kunihide Ohashi ◽  
Yasutaka Kawanami ◽  
Björn Windén ◽  
...  
Keyword(s):  
Energy Saving ◽  
Full Scale ◽  
Container Ship ◽  
Bulk Carrier

scholarly journals High-Performance Accuracy of Daylight-Responsive Dimming Systems with Illuminance by Distant Luminaires for Energy-Saving Buildings

Energies ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 731 ◽  
Author(s):  
In-Tae Kim ◽  
Yu-Sin Kim ◽  
Meeryoung Cho ◽  
Hyeonggon Nam ◽  
Anseop Choi ◽  
...  
Keyword(s):  
Energy Saving ◽  
High Performance ◽  
Control Algorithm ◽  
Energy Savings ◽  
Prediction Method ◽  
Full Scale ◽  
Performance Accuracy ◽  
Photo Sensor ◽  
Lighting Energy ◽  
Dimming Control

In a conventional daylight-responsive dimming system (DRDS), all the luminaires are turned off during the calibration process except for the luminaire under consideration in order to sense only the workplane illuminance of that luminaire. However, the workplane illuminance of the luminaire is influenced by other luminaires. Therefore, the final workplane illuminance of the actual operated system is higher than the target workplane illuminance, reducing the energy-saving efficiency of the DRDS. Herein, to improve the conventional DRDS, an advanced commissioning prediction method of daylight illuminance, and a dimming control algorithm considering the influences by distant luminaires are proposed. To evaluate the accuracy of the proposed prediction method of daylight illuminance, the daylight illuminance on the workplane and the photo sensor values of six points were measured in a full-scale mockup for 27 consecutive days from 22 June to 18 July 2018. As a result of root-mean-square error (RMSE) analysis of daylight illuminance and the photo sensor values, the RMSE (64.86) of P3 located in the middle of the room was the highest, and the RMSE value (17.60) of P5 located near the window was the lowest. In addition, the power consumption of the luminaires, and the target illuminance accuracy of the proposed DRDS were measured and analyzed for 32 consecutive days from 19 July to 19 August 2018 in a full-scale mockup. The average target illuminance accuracy was 96.9% (SD 2.2%), the average lighting energy-savings ratio was 78.4%, and the daylight illuminance prediction accuracy was 95.5% (SD 3.4%).

scholarly journals EXPERIMENT AND ANALYSIS OF THE ENERGY-SAVING EFFECT OF THE WATER HOLDING PROPERTY MATERIALS USING A FULL-SCALE BUILDING

2008 ◽  
Vol 36 ◽  
pp. 419-425
Author(s):  
Hiroyuki YAMADA ◽  
Akinori TANAKA ◽  
Yoshio OKUDA ◽  
Takaharu ICHIRYU
Keyword(s):  
Energy Saving ◽  
Full Scale ◽  
Saving Effect ◽  
Water Holding
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