scholarly journals Field Test and Analysis of Energy-Saving Effects of Energy-Recovery Ventilators on Heat-Pump Electricity Consumption in a Classroom

2019 ◽  
Vol 11 (7) ◽  
pp. 2069
Author(s):  
Jae-Sol Choi ◽  
Eui-Jong Kim
Keyword(s):  
Energy Saving ◽  
Field Test ◽  
Energy Recovery ◽  
Field Tests ◽  
High Energy ◽  
Heat Pumps ◽  
Test Method ◽  
Actual System ◽  
Experimental Conditions ◽  
Saving Rates

Energy-recovery ventilators (ERVs) are regarded as important energy-saving systems in buildings. It has been reported that they have high energy-saving rates compared with conventional ventilators that operate without energy recovery, but the saving rates have been obtained typically by employing chamber tests and simulations. In this work, a field-test method is proposed that uses a single test room but alternates the tested ventilation modes hourly. This proposed method is useful because an additional comparison room is not always available and can be a source of uncertainty for field tests. The test is performed in a classroom during a heating period, and the results are calibrated to account for different experimental conditions during the test period. The calibrated energy-saving rates indicate the effectiveness of the ERV; however, they are lower in the early hours of the system operation, for two reasons: (1) the maximum power control schemes of the heat pumps are applied for cases where the indoor temperatures are far lower than the set-point temperature; (2) the ventilation load seemingly represents a decreasing proportion of the total heating load in early hours owing to the thermal-capacity effects for the building, which was cooled for many hours. The findings are verified via a chamber test and simulations. As a consequence, it is important to account for actual system characteristics affected by the thermal behaviors of classrooms when the overall performance of a system is evaluated.

The importance of aerodynamics for prosthetic limb design used by competitive cyclists with an amputation: An introduction

2014 ◽  
Vol 39 (3) ◽  
pp. 232-237 ◽  
Author(s):  
Bryce Dyer
Keyword(s):  
Field Test ◽  
Aerodynamic Drag ◽  
Field Tests ◽  
Field Testing ◽  
Test Method ◽  
Limb Amputation ◽  
Small Scale ◽  
Prosthetic Limb ◽  
Testing Method ◽  
Competitive Cyclists

Background/Objectives: This study introduces the importance of the aerodynamics to prosthetic limb design for athletes with either a lower-limb or upper-limb amputation. Study design: The study comprises two elements: 1) An initial experiment investigating the stability of outdoor velodrome-based field tests, and 2) An experiment evaluating the application of outdoor velodrome aerodynamic field tests to detect small-scale changes in aerodynamic drag respective of prosthetic limb componentry changes. Methods: An outdoor field-testing method is used to detect small and repeatable changes in the aerodynamic drag of an able-bodied cyclist. These changes were made at levels typical of alterations in prosthetic componentry. The field-based test method of assessment is used at a smaller level of resolution than previously reported. Results: With a carefully applied protocol, the field test method proved to be statistically stable. The results of the field test experiments demonstrate a noticeable change in overall athlete performance. Aerodynamic refinement of artificial limbs is worthwhile for athletes looking to maximise their competitive performance. Conclusion: A field-testing method illustrates the importance of the aerodynamic optimisation of prosthetic limb components. The field-testing protocol undertaken in this study gives an accessible and affordable means of doing so by prosthetists and sports engineers. Clinical relevance Using simple and accessible field-testing methods, this exploratory experiment demonstrates how small changes to riders’ equipment, consummate of the scale of a small change in prosthetics componentry, can affect the performance of an athlete. Prosthetists should consider such opportunities for performance enhancement when possible.

Characteristics Analysis of Pneumatic Booster Valve With Energy Recovery

2016 ◽  
Author(s):  
Fan Yang ◽  
Kotaro Tadano ◽  
Gangyan Li ◽  
Toshiharu Kagawa
Keyword(s):  
Energy Efficiency ◽  
Energy Saving ◽  
Flow Rate ◽  
Pressure Fluctuation ◽  
Energy Recovery ◽  
High Energy ◽  
State Equation ◽  
Conservation Equation ◽  
Local Pressure ◽  
Supply Pressure

Pneumatic booster valve is widely used in local pressure boost circuit for energy saving, a new booster valve with energy recovery (short for BVER) was proposed in this paper in order to further improve the energy efficiency. Firstly, the principle of BVER was introduced by comparing with the traditional booster. Based on flow-rate characteristics equation, gas state equation, energy conservation equation, etc., the mathematics model of BVER was established, and the flow-rate characteristics, boost ratio, pressure in tank and energy efficiency were systematically analyzed by simulation. Lastly, the model was verified by experiments. This study shows that: firstly, the pressure decreased sharply with the flow-rate’s increasing, and the pressure in tank is much lower than in BVER. Secondly, the boost ratio was affected by supply pressure, regulator coefficient and the diameter of recovery chamber. Thirdly, the pressure fluctuation in tank decreases with the tank volume increasing, and the pressure fluctuation is less than 1% when tank volume is larger than 10L. Lastly, the energy efficiency will increase 5∼10 percent with the boost ratio increases 15∼25 percent under different supply pressure. This study proves that BVER has better performance than VBA for its high boost ratio and high energy efficiency, and it provides a reference for booster valve’s design and energy saving.

scholarly journals Predicting the durability of zinc coatings based on laboratory and field tests

2019 ◽  
Vol 121 ◽  
pp. 01008
Author(s):  
Mark Kovalev ◽  
Ekaterina Alekseeva ◽  
Nikita Shaposhnikov ◽  
Anton Povyshev
Keyword(s):  
Corrosion Rate ◽  
Thermal Diffusion ◽  
Field Test ◽  
Laboratory Tests ◽  
Field Tests ◽  
Test Method ◽  
Laboratory Studies ◽  
Corrosion Rates ◽  
Zinc Coatings ◽  
Salt Fog

Galvanizing is one of the most common methods of corrosion protection. For the deposition of zinc coatings used such methods as gas-thermal deposition, thermal diffusion saturation in powder, hot-dip galvanizing, cladding, and galvanic precipitating during electrolysis. The hot-dip galvanizing is the most common method, which is used in construction, automotive and other industries. Paper presents the results of research of zinc coatings used in sea conditions. The aim of the work was to determine an acceleration factor by comparing the corrosion rate in laboratory conditions with the data from field tests. Laboratory studies were carried out in a salt fog chamber. Samples were periodically removed from chamber to build the dependence of the corrosion rate on the exposure time. Field tests were carried out at the exploitation area. Result of the work is a guide that allows to predict the corrosion rates of zinc coatings using laboratory tests. The advantage of this test method is shorter time of exposure in comparison with field test.

scholarly journals Towards a field test for fracture propagation propensity in weak snowpack layers

2006 ◽  
Vol 52 (176) ◽  
pp. 164-168 ◽  
Author(s):  
Dave Gauthier ◽  
Bruce Jamieson
Keyword(s):  
Field Test ◽  
Fracture Propagation ◽  
Field Tests ◽  
Fracture Initiation ◽  
Bimodal Distribution ◽  
Test Method ◽  
Flexural Wave ◽  
Weak Layer ◽  
Columbia Mountains ◽  
Initiation And Propagation

AbstractSlab avalanche release requires fracture initiation and propagation in a weak snowpack layer. While field tests of weak-layer strength are useful for fracture initiation, the challenge remains to find a verified field test for fracture propagation. We introduce the two current versions of a field test for fracture propagation propensity, and report results of testing conducted in the Columbia Mountains of British Columbia, Canada, during the winter of 2005. By extending the column of a stability test approximately 3 m in the downslope direction, the test method allows for the development of a flexural wave in the slab, and thereby maintains the contribution of this wave and the associated weak-layer collapse to the fracture process. Fracture lengths collected on a day and location where the propagation propensity of the snowpack was locally high show a bimodal distribution, with approximately 50% of observed fractures similar to those collected in stable snowpacks, and approximately 50% with much longer fracture lengths.

scholarly journals The Analysis of Shuttlecock Velocity Based on the Field Test Method of The Home Industry Products in Indonesia

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Ucup Yusup ◽  
Agus Rusdiana
Keyword(s):  
Field Test ◽  
Initial Velocity ◽  
Field Tests ◽  
Test Method ◽  
Final Velocity ◽  
3D Motion Analysis ◽  
Analysis System ◽  
Main Components ◽  
Home Industries

One of the main components of badminton games is shuttlecock. The shuttlecock home industries in Indonesia mainly employ for about 20-40 freelance workers. The workers in the home industries are able to produce 500-100 slops of shuttlecock daily. The guarantee of the shuttlecock quality produced by home industries, either through the laboratory tests or field tests, is rarely conducted formally. Therefore, we are interested in conducting an academic study on the velocity of the shuttlecocks produced by the workers of the shuttlecock home industries that have been distributed in Indonesia markets. There are eight widely distributed shuttlecock brands produced by the home industries in Indonesia, including Taiso, Saporate, Netra, Arjuna, Kuda Mas, Rivals, Purnama, and Spin. The purpose of this study was to examine the quality of aerodynamics rate of the shuttlecock produced by home industries by comparing the rate of motion of the shuttlecock in different distances started from the initial velocity to the final velocity when the shuttlecocks impact to the ground. The method used in this study was a descriptive qualitative study. The instruments used were three high resolution handy cams, a set of calibration, and the 3D motion analysis system software (Frame Diaz IV). The result of this study showed that the average velocity of the shuttlecock, started from the initial velocity to the final velocity with 5 meter distance, reached 85.0 m/s., while the average final velocity reached 29.8m/s at 5 meter distance. From all of the shuttlecock types tested in the field test for their velocity, it was found that the Spin brand moved with a high velocity with 12.8% of percentage. Meanwhile, the lowest velocity of the shuttlecock was found in the Taiso brand where the percentage was 15.3% in 9 meter and12 meter distances. The study concludes that the average of various shuttlecock brands’ speeds are in the normal category except for the Taiso and Spin brands.

Modeling and Simulation of Boom Potential Energy Recovery System in Hybrid Hydraulic Excavator

2013 ◽  
Vol 437 ◽  
pp. 217-221 ◽  
Author(s):  
Bao Yu Cao ◽  
Wei Li ◽  
Zhe Tong
Keyword(s):  
Potential Energy ◽  
Modeling And Simulation ◽  
Energy Saving ◽  
Energy Recovery ◽  
High Energy ◽  
Excess Energy ◽  
Hydraulic Excavator ◽  
Energy Recovery System ◽  
Recovery System ◽  
Hydraulic Cylinders

Hydraulic excavator energy-saving is important to relieve source shortage and protect environment. This paper mainly discusses the energy saving for the hybrid hydraulic excavator. By analyzing the excess energy of three hydraulic cylinders in the conventional hydraulic excavator, a new boom potential energy recovery system is proposed. At last, the model of the proposed system has been built by AMESim. The simulation result shows that the proposed boom potential energy recovery system has a high energy saving efficiency.

scholarly journals Hair whorls of Holstein Friesian heifers and affects on growth and behaviour

2007 ◽  
Vol 50 (4) ◽  
pp. 374-380
Author(s):  
J. Broucek ◽  
P. Kisac ◽  
S. Mihina ◽  
A. Hanus ◽  
M. Uhrincat ◽  
...  
Keyword(s):  
Body Weight ◽  
Dairy Cattle ◽  
Open Field ◽  
Field Test ◽  
Open Field Test ◽  
Field Tests ◽  
Experimental Conditions ◽  
Holstein Friesian

Abstract. The aim of this study was to investigate whether the growth, number of crossed squares in the open-field test and time of traversing the maze in the maze are affected by the height position of they facial whorl in heifers which were kept in experimental conditions. Fifty-eight Holstein heifers were used. The hair whorl position was determined as hair whorl high, middle and low. Heifers with a high whorl had significantly higher body weight at days 360 (P<0.05) and 540 (P<0.01) and average daily gains from birth to 21 months (P<0.001) and from the 6th to 21st months (P<0.01) of age. We did not find any significant differences among hair whorl position groups either in open-field tests or in the maze. The present results show that the growth is influenced in the investigated dairy cattle by height of their facial whorl.

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