DETERMINATION AND ANALYSIS OF THE THEORETICAL PRODUCTION OF A BUCKET WHEEL EXCAVATOR

2014 ◽  
Vol 59 (1) ◽  
pp. 283-291
Author(s):  
Che Zhao-Xue ◽  
Chen Yan-Long
Keyword(s):  
Material Flow ◽  
Capacity Utilization ◽  
Structure Parameters ◽  
Nonuniform Flow ◽  
Performance Parameters ◽  
Drive Power ◽  
Rotary Speed ◽  
And Performance ◽  
Mathematical Derivation ◽  
Rotary Drive

Abstract The theoretical capacity of a bucket wheel excavator is the basis of mining theory. The paper concludes that the use of “1/cosφ” to adjust the speed of a bucket wheel excavator will result in rapid speeds, which may cause nonuniform flow from the distribution of material flow, and decreased capacity utilization. Consequently, this scenario may produce unreasonable structure parameters and performance parameters that are based on theoretical analysis and mathematical derivation. If the rotary speed of an excavator body is too fast, it will require excessive mechanical strength and will generate increased rotary drive power, power consumption and extractive costs. Thus, the rotary speed of an excavator body should be appropriately reduced.

scholarly journals Modeling and Simulation of 115.2 kWp Grid-Connected Solar PV System using PVSYST

2018 ◽  
Vol 1 (1) ◽  
pp. 31-34 ◽  
Author(s):  
Ashok Aryal ◽  
Nawraj Bhattarai
Keyword(s):  
Capacity Utilization ◽  
University Teaching ◽  
Performance Ratio ◽  
Specific Yield ◽  
Performance Parameters ◽  
Solar Pv ◽  
Pv System ◽  
Utilization Factor ◽  
Solar Pv System ◽  
And Performance

The renewable sources such as solar, wind, biomass, etc. are often used for electricity generation for their availability, no green-house gas emission and solar photovoltaic is major among them. Many On-Grid PV systems are being installed around the globe nowadays to reduce electricity dependency on a single source and thus enhance availability of energy sources. Kathmandu, Nepal receives sufficient sunshine with insolation around 4.5 to 5 kWh/m2/day, which justifies essence of grid-connected solar PV installations. A 115.2 kWp solar plant has been installed at Tribhuvan University Teaching Hospital (TUTH), Maharajgunj, Kathmandu to fulfill its own load demands and reduce the electricity bill of the building. The generated energy is not fed to the grid currently. The detailed On-Grid solar PV system is modeled, and performance parameters such as Performance Ratio, Specific Yield and Capacity Utilization Factor as defined by International Electro technical Commission are estimated using simulation techniques from PVSYST. The actual generation of the existing system within one year of installation is measured to be 35 MWh but simulation tool suggests that total 199 MWh can be generated using similar capacity panel, with system being totally on-grid type. Using PVSYST, the performance parameters are found to be performance ratio 83.5 % and Specific Yield 1728 kWh/kWp respectively. Thus, this paper intends to calculate performance parameters of existing system as well as performance of identical sized, totally on-grid system, simulated using PVSYST.

Effect of Feeding Bt176 Maize on Physiological and Performance Parameters in Broiler Chickens

2004 ◽  
Vol 15 (3) ◽  
pp. 246-246
Author(s):  
M.A. Tony ◽  
A. Butschke ◽  
J. Zagon ◽  
H. Broll ◽  
M. Schauzu ◽  
...  
Keyword(s):  
Broiler Chickens ◽  
Performance Parameters ◽  
And Performance ◽  
Effect Of Feeding

scholarly journals Comparison of a Novel Polymeric Hollow Fiber Heat Exchanger and a Commercially Available Metal Automotive Radiator

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1175
Author(s):  
Tereza Kroulíková ◽  
Tereza Kůdelová ◽  
Erik Bartuli ◽  
Jan Vančura ◽  
Ilya Astrouski
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Hollow Fiber ◽  
Pressure Loss ◽  
Air Flow ◽  
Performance Parameters ◽  
University Of Technology ◽  
Flat Tubes ◽  
And Performance ◽  
Louvered Fins

A novel heat exchanger for automotive applications developed by the Heat Transfer and Fluid Flow Laboratory at the Brno University of Technology, Czech Republic, is compared with a conventional commercially available metal radiator. The heat transfer surface of this heat exchanger is composed of polymeric hollow fibers made from polyamide 612 by DuPont (Zytel LC6159). The cross-section of the polymeric radiator is identical to the aluminum radiator (louvered fins on flat tubes) in a Skoda Octavia and measures 720 × 480 mm. The goal of the study is to compare the functionality and performance parameters of both radiators based on the results of tests in a calibrated air wind tunnel. During testing, both heat exchangers were tested in conventional conditions used for car radiators with different air flow and coolant (50% ethylene glycol) rates. The polymeric hollow fiber heat exchanger demonstrated about 20% higher thermal performance for the same air flow. The efficiency of the polymeric radiator was in the range 80–93% and the efficiency of the aluminum radiator was in the range 64–84%. The polymeric radiator is 30% lighter than its conventional metal competitor. Both tested radiators had very similar pressure loss on the liquid side, but the polymeric radiator featured higher air pressure loss.

scholarly journals Effect of Dam Depth and Relief Track Depth on Steady-State and Dynamic Performance Parameters of 3-Lobe Pressure Dam Bearing

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Ashutosh Kumar ◽  
S. K. Kakoty
Keyword(s):  
Steady State ◽  
Dynamic Performance ◽  
Performance Characteristics ◽  
Performance Parameters ◽  
Effect Of Pressure ◽  
And Performance

The present study analyzes the effect of pressure dam depth and relief track depth on the performance of three-lobe pressure dam bearing. Different values of dam depth and relief track depth are taken in nondimensional form in order to analyze their effect. Results are plotted for different parameters against eccentricity ratios and it is shown that the effect of pressure dam depth and relief track depth has great significance on stability and other performance parameters. Study of stability and performance characteristics is undertaken simultaneously.

scholarly journals Doses of caffeine on the development and performance of pepper crops under greenhouse

2014 ◽  
Vol 32 (4) ◽  
pp. 398-403 ◽  
Author(s):  
Óscar Montes ◽  
Fernando Diánez ◽  
Francisco Camacho
Keyword(s):  
Fruit Quality ◽  
Cycle Performance ◽  
Morphological Development ◽  
Performance Parameters ◽  
Stimulant Effect ◽  
Plant Organs ◽  
Vegetative Plant ◽  
Production Parameters ◽  
Growth Stimulator ◽  
And Performance

A number of experiments on plant organs demonstrated that caffeine acts as a growth stimulator. In this study we aimed to determine the influence of caffeine on development of pepper crops under stress in the autumn-winter cycle, as peppers stop growing and developing in November and January. The experiments were conducted to determine how caffeine applied to the soil by fertigation, with doses of 2.25 µM and 9.00 µM for T1 and T2, respectively, compared to the control crop, affect the morphological development and performance of the pepper crops during two crop cycles (2008-2009 and 2009-2010 in autumn-winter). Throughout the whole vegetative plant cycle, performance parameters of fruit quality and the influence on the morphological development were obtained on different dates. With respect to the remainder of the morphological and production parameters, no significant differences were discovered in either of the evaluated cycles, thus leading to the conclusion that the two doses of caffeine, 2.25 µM and 9.00 µM, did not have any stimulant effect on the development and performance of the pepper crop during both cycles. Total yields were unaffected by either treatment, 4.89, 4.90 and 4.88 kg/m2 for the first assay and 5.28, 5.23 and 5.28 for the second, for treatments control and caffeine dosses 2.25 µM y 9.00 µM respectively.

scholarly journals Exclusive Characteristics and Management, Status and Performance Parameters of Balochi Sheep

2020 ◽  
Vol 9 (5) ◽  
Author(s):  
Mudassar Jehan ◽  
Masroor Ahmed Bajwa ◽  
Mohammad Masood Tariq ◽  
Asim Faraz ◽  
Ecevit Eyduran ◽  
...  
Keyword(s):  
Performance Parameters ◽  
And Performance

scholarly journals BIM Enabled Approach for Performance-Based Design

2018 ◽  
Vol 7 (4) ◽  
pp. 1-27
Author(s):  
Renas K.M. Sherko ◽  
Yusuf Arayici ◽  
Mike Kagioglou
Keyword(s):  
Technology Use ◽  
Building Design ◽  
Energy Performance ◽  
Performance Based Design ◽  
Design Parameters ◽  
Performance Parameters ◽  
Efficient Design ◽  
Architectural Practice ◽  
Study Approach ◽  
And Performance

A significant amount of energy is consumed by buildings due to ineffective design decisions with little consideration for energy efficiency. Yet, performance parameters should be considered during the early design phase, which is vital for improved energy performance and lower CO2 emissions. BIM, as a new way of working methodology, can help for performance-based design. However, it is still infancy in architectural practice about how BIM can be used to develop energy efficient design. Thus, the aim is to propose a strategic framework to guide architects about how to do performance-based design considering the local values and energy performance parameters. The research adopts a multi case study approach to gain qualitative and quantitative insights into the building energy performance considering the building design parameters. The outcome is a new design approach and protocol to assist designers to successfully use BIM for design optimization, PV technology use in design, rules-based design and performance assessment scheme reflecting local values.

scholarly journals Physiological Responses and Predictors of Performance in a Simulated Competitive Ski Mountaineering Race

2021 ◽  
pp. 250-257
Author(s):  
Michael Lasshofer ◽  
John Seifert ◽  
Anna-Maria Wörndle ◽  
Thomas Stöggl
Keyword(s):  
Laboratory Test ◽  
Power Output ◽  
Ventilatory Threshold ◽  
Elite Athletes ◽  
Physiological Responses ◽  
Performance Parameters ◽  
Ramp Test ◽  
The Past ◽  
Treadmill Speed ◽  
And Performance

Competitive ski mountaineering (SKIMO) has achieved great popularity within the past years. However, knowledge about the predictors of performance and physiological response to SKIMO racing is limited. Therefore, 21 male SKIMO athletes split into two performance groups (elite: VO2max 71.2 ± 6.8 ml· min-1· kg-1 vs. sub-elite: 62.5 ± 4.7 ml· min-1· kg-1) were tested and analysed during a vertical SKIMO race simulation (523 m elevation gain) and in a laboratory SKIMO specific ramp test. In both cases, oxygen consumption (VO2), heart rate (HR), blood lactate and cycle characteristics were measured. During the race simulation, the elite athletes were approximately 5 min faster compared with the sub-elite (27:15 ± 1:16 min; 32:31 ± 2:13 min; p < 0.001). VO2 was higher for elite athletes during the race simulation (p = 0.046) and in the laboratory test at ventilatory threshold 2 (p = 0.005) and at maximum VO2 (p = 0.003). Laboratory maximum power output is displayed as treadmill speed and was higher for elite than sub-elite athletes (7.4 ± 0.3 km h-1; 6.6 ± 0.3 km h-1; p < 0.001). Lactate values were higher in the laboratory maximum ramp test than in the race simulation (p < 0.001). Pearson’s correlation coefficient between race time and performance parameters was highest for velocity and VO2 related parameters during the laboratory test (r > 0.6). Elite athletes showed their superiority in the race simulation as well as during the maximum ramp test. While HR analysis revealed a similar strain to both cohorts in both tests, the superiority can be explainable by higher VO2 and power output. To further push the performance of SKIMO athletes, the development of named factors like power output at maximum and ventilatory threshold 2 seems crucial.

scholarly journals Regenerated Marine Gas Turbines: Part II — Regenerator Technology and Heat Exchanger Sizing

1982 ◽  
Author(s):  
J. W. Watts ◽  
T. L. Bowen
Keyword(s):  
Heat Exchanger ◽  
Pressure Drop ◽  
Performance Improvement ◽  
Gas Turbines ◽  
Performance Parameters ◽  
Next Generation ◽  
Plate Spacing ◽  
Naval Ship ◽  
And Performance ◽  
Regenerative Cycle

Analytical studies are currently being conducted by the David Taylor Naval Ship R&D Center to assess the suitability of regenerative-cycle and intercooled, regenerative-cycle gas turbines for naval applications. This paper is the second part of a two-part paper which discusses results of initial investigations to identify attractive engine concepts based on existing turbomachinery and to consider the regenerator technology required to develop these engine concepts. Part I of the paper analyzed existing and next generation engines for performance improvement. Part II includes: definitions of performance parameters such as effectiveness and pressure drop, a discussion of regenerator types, and comments on regenerator materials, life, maintenance, and fouling. Tradeoffs between size, weight, and performance of plate-fin recuperators are examined using two of the hypothetical engines from Part I as examples. Results are compared for several different recuperator matrices to illustrate the effects of air-side and gas-side fin density and plate spacing on size, weight, and performance.

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