Power, efficiency, ecological function and ecological coefficient of performance optimizations of irreversible Diesel cycle based on finite piston speed

Abstract A model for the quantum Brayton refrigerator that takes the harmonic oscillator system as the working substance is established. Expressions of cooling load, coefficient of performance (COP), and ecological function are derived. With numerical illustrations, the optimal ecological performance is investigated. At the same time, effects of heat leakage and quantum friction are also studied. For the case with the classical approximation, the optimal ecological performance, and effects of heat leakage and quantum friction are also investigated. For both general cases and the case with classical approximation, the results indicate that the ecological function has a maximum. The irreversible losses decrease the ecological performance, while having different effects on the optimal ecological performance. For the case with classical approximation, numerical calculation with friction coefficient μ = 0.02 and heat leakage coefficient Ce = 0.01 shows that the cooling load (RE) at the maximum ecological function is 6.23% smaller than the maximum cooling load (Rmax). The COP is also increased by 12.1%, and the exergy loss rate is decreased by 27.6%. Compared with the maximum COP state, the COP (ɛE) at the maximum ecological function is 0.55% smaller than the maximum COP (ɛmax) and that makes 7.63% increase in exergy loss rate, but also makes 6.17% increase in cooling load and 6.20% increase in exergy output rate.

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Optimization of the power, efficiency and ecological function for an air-standard irreversible Dual-Miller cycle

Frontiers in Energy ◽

10.1007/s11708-018-0557-z ◽

2018 ◽

Vol 13 (3) ◽

pp. 579-589 ◽

Cited By ~ 2

Author(s):

Zhixiang Wu ◽

Lingen Chen ◽

Yanlin Ge ◽

Fengrui Sun

Keyword(s):

Power Efficiency ◽

Ecological Function ◽

Miller Cycle

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Performance Characteristics of a Compressor-Driven Metal Hydride Refrigerator

Journal of Energy Resources Technology ◽

10.1115/1.2795052 ◽

1998 ◽

Vol 120 (4) ◽

pp. 305-313 ◽

Cited By ~ 3

Author(s):

G. M. Lloyd ◽

A. Razani ◽

K. J. Kim

Keyword(s):

Metal Hydride ◽

Power Efficiency ◽

Performance Comparison ◽

Coefficient Of Performance ◽

Thermodynamic Efficiency ◽

Operating Characteristics ◽

Actual System ◽

Transient Conditions ◽

System Operating ◽

The Ideal

Thermodynamic analyses of compressor-driven metal hydride refrigerators predict a high coefficient of performance. Comparison with the results from a computational model indicates that the coefficient of performance attainable from an actual system operating under transient conditions can indeed be significant. Parametric calculations are given which illustrate the ideal power-efficiency operating characteristics of the system. The computed efficiency approaches the thermodynamic efficiency as the operating power tends to zero.

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Investigation on Operating Processes for a New Solar Cooling Cogeneration Plant

Journal of Solar Energy Engineering ◽

10.1115/1.4027423 ◽

2014 ◽

Vol 136 (3) ◽

Cited By ~ 18

Author(s):

R. Shankar ◽

T. Srinivas

Keyword(s):

Power Generation ◽

Thermal Efficiency ◽

Power Efficiency ◽

Climatic Conditions ◽

Coefficient Of Performance ◽

Maximum Temperature ◽

Specific Power ◽

Working Fluid ◽

Water Mixture ◽

Cogeneration Plant

Some commercial units and industries need more amount of cooling than the power such as cold storage, shopping complex, etc. In this work, a new cooling cogeneration cycle (Srinivas cycle) has been proposed and solved to generate more cooling with adequate power generation from single source of heat at hot climatic conditions with ammonia–water mixture as a working fluid. The operational processes conditions for the proposed cooling cogeneration plant are different compared to the power-only (Kalina cycle system) system and cooling-only (vapor absorption refrigeration) system. This work focused to generate the optimum working conditions by parametric analysis from thermodynamic point of view. An increase in cycle maximum temperature is only supporting the power generation but not the cooling output. Cooling output is also 15 times more than power generation. So, it has been recommended to operate the integrated plant with low temperature heat recovery. The resulted cycle thermal efficiency, plant thermal efficiency, specific power, specific cooling, cycle power efficiency, cycle coefficient of performance (COP), and solar collector's specific area are 27%, 10%, 15 kW, 220 kW, 1.8%, 0.25, and 10 m2/kW, respectively.

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POWER-EFFICIENCY ANALYSIS OF OIL WELL SYSTEMS WITH SUCKER ROD PUMPING UNITS

Oil and Gas Studies ◽

10.31660/0445-0108-2015-4-80-84 ◽

2015 ◽

pp. 80-84

Author(s):

A. M. Sagdatullin

Keyword(s):

Power Consumption ◽

Power Efficiency ◽

Efficiency Analysis ◽

Coefficient Of Performance ◽

Oil Well ◽

Half Cycle ◽

Chain Drive ◽

Sucker Rod ◽

A Chain ◽

Pumping Units

The purpose of this paper is to analyze the power efficiency of oil well systems with sucker rod pumping units. For this study a chain-drive of HRC 80-6-02 type and a similar performance drive HRC 80-6-02 balancer pumping unit were selected. Based on the analysis of the data, a conclusion was made that the power consumption for production of oil using ESP units is much higher due to a low coefficient of performance (COP) and significant losses in the submerged electric-driven pump. The analysis showed that for a half cycle of operation, i.e. per one stroke, the power consumption by a jack-pump was 15-20% higher than that of the chain drive. It is concluded that the chain drive is superior in many aspects of sucker-rod pumping units operation and may be the most effective replacement for ESP units, as well as for units with walking-beam jack pumps.

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RESEARCH OF INDICATORS OF A VEHICLE WITH A DIESEL WORKING ON DIESEL AND DIESEL GAS CYCLES USING THE MATHEMATICAL MODEL

Avtoshliakhovyk Ukrayiny ◽

10.33868/0365-8392-2020-1-261-14-19 ◽

2020 ◽

pp. 14-19

Author(s):

Serhii Kovbasenko ◽

Andriy Holyk ◽

Serhii Hutarevych

Keyword(s):

Mathematical Model ◽

Diesel Engine ◽

Environmental Performance ◽

Energy Performance ◽

Dual Fuel ◽

Fuel System ◽

Compressed Natural Gas ◽

Diesel Vehicles ◽

Diesel Cycle ◽

The Mathematical Model

The features of an advanced mathematical model of motion of a truck with a diesel engine operating on the diesel and diesel gas cycles are presented in the article. As a result of calculations using the mathematical model, a decrease in total mass emissions as a result of carbon monoxide emissions is observed due to a decrease in emissions of nitrogen oxides and emissions of soot in the diesel gas cycle compared to the diesel cycle. The mathematical model of a motion of a truck on a city driving cycle according to GOST 20306-90 allows to study the fuel-economic, environmental and energy indicators of a diesel and diesel gas vehicle. The results of the calculations on the mathematical model will make it possible to conclude on the feasibility of converting diesel vehicles to using compressed natural gas. Object of the study – the fuel-economic, environmental and energy performance diesel engine that runs on dual fuel system using CNG. Purpose of the study – study of changes in fuel, economic, environmental and energy performance of vehicles with diesel engines operating on diesel and diesel gas cycles, according to urban driving cycle modes. Method of the study – calculations on a mathematical model and comparison of results with road tests. Bench and road tests, results of calculations on the mathematical model of motion of a truck with diesel, working on diesel and diesel gas cycles, show the improvement of environmental performance of diesel vehicles during the converting to compressed natural gas in operation. Improvement of environmental performance is obtained mainly through the reduction of soot emissions and nitrogen oxides emissions from diesel gas cycle operations compared to diesel cycle operations. The results of the article can be used to further develop dual fuel system using CNG. Keywords: diesel engine, diesel gas engine, CNG

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Effect of Shielding a Floating Electrode on the Power Efficiency of a Micro-plasma VUV Light Source

IEEJ Transactions on Sensors and Micromachines ◽

10.1541/ieejsmas.135.114 ◽

2015 ◽

Vol 135 (3) ◽

pp. 114-115 ◽

Cited By ~ 1

Author(s):

Ryoto Sato ◽

Daisuke Yasumatsu ◽

Shinya Kumagai ◽

Masaru Hori ◽

Minoru Sasaki

Keyword(s):

Light Source ◽

Power Efficiency ◽

Floating Electrode

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EXPERIMENTAL AND ANALYTICAL STUDIES OF VERTICAL AXIS WIND TURBINES

Alternative Energy and Ecology (ISJAEE) ◽

10.15518/isjaee.2018.22-24.051-058 ◽

2018 ◽

pp. 51-58

Author(s):

B. P. Khozyainov

Keyword(s):

Wind Turbine ◽

Flow Velocity ◽

Wind Power ◽

Wind Turbines ◽

Power Efficiency ◽

Air Flow ◽

Geometrical Parameters ◽

Wind Speeds ◽

Analytical Studies ◽

Air Flow Velocity

The article carries out the experimental and analytical studies of three-blade wind power installation and gives the technique for measurements of angular rate of wind turbine rotation depending on the wind speeds, the rotating moment and its power. We have made the comparison of the calculation results according to the formulas offered with the indicators of the wind turbine tests executed in natural conditions. The tests were carried out at wind speeds from 0.709 m/s to 6.427 m/s. The wind power efficiency (WPE) for ideal traditional installation is known to be 0.45. According to the analytical calculations, wind power efficiency of the wind turbine with 3-bladed and 6 wind guide screens at wind speedsfrom 0.709 to 6.427 is equal to 0.317, and in the range of speed from 0.709 to 4.5 m/s – 0.351, but the experimental coefficient is much higher. The analysis of WPE variations shows that the work with the wind guide screens at insignificant average air flow velocity during the set period of time appears to be more effective, than the work without them. If the air flow velocity increases, the wind power efficiency gradually decreases. Such a good fit between experimental data and analytical calculations is confirmed by comparison of F-test design criterion with its tabular values. In the design of wind turbines, it allows determining the wind turbine power, setting the geometrical parameters and mass of all details for their efficient performance.

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