Off-design Characteristics for Ambient Air Temperature and Turbine Load of Gas Turbine Pre-swirl System

Energy and exergy analyses were carried out on an active 42MW open cycle gas turbine power plant. Data from the power plant record book were employed in the investigation. The First and Second Laws of Thermodynamics were applied to each component of the gas power plant at ambient air temperature range of 21 - 330C. Results obtained from the analyses show that the energy and exergy efficiencies decrease with increase in ambient air temperature entering the compressor. It was also shown that 66.98% of fuel input and 54.53% of chemical exergy are both lost to the environment as heat from the combustion chamber in the energy and exergy analysis respectively. The energy analysis quantified the efficiency of the plant arising from energy losses , while exergy analysis revealed the magnitude of losses in various components of the plant. Therefore a complete thermodynamic evaluation of gas turbine power plants requires the use of both analytical methods.

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Exergy Analysis of a Micro-Gas Turbine Fueled with Syngas

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.465-466.142 ◽

2013 ◽

Vol 465-466 ◽

pp. 142-148

Author(s):

Hussain Sadig ◽

Shaharin Anwar Sulaiman ◽

Ibrahim Idris

Keyword(s):

Combustion Chamber ◽

Gas Turbine ◽

Air Temperature ◽

Heat Input ◽

Ambient Air ◽

Exergy Destruction ◽

Exergetic Efficiency ◽

Micro Gas Turbine ◽

Ambient Air Temperature ◽

Excess Air

A theoretical exergetic analysis of a small-scale gas-turbine system fueled with two different syngas fuels is discussed in this paper. For carrying out the analysis, a micro-gas turbine system with a thermal heat input of 50 kW was simulated using ASPEN plus simulator. Quantitative exergy balance was applied for each component in the cycle. The effects of excess air, ambient air temperature, and heat input on the exergy destruction and exergetic efficiency for each component were evaluated and compared with those resulted from fueling the system with liquefied petroleum gas (LPG). For 50 kW heat input and 50% excess air, the total exergy destruction for LPG, Syngas1, and Syngas2 were found to be 17.3, 14.3, and 13.6 kW, respectively. It was found that increasing the excess air ratio to 100% increased the combustion chamber exergetic efficiency by 8%-10% but it reduced the exergetic efficiency of other components. The same trend was observed when tested ambient air temperature. The results also showed a reduction in the combustion chamber exergetic efficiency by 2%-4% when a 20% heat input increase was applied.

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Control Strategies for VHTR Gas-Turbine System With Dry Cooling

Volume 2: Plant Systems, Structures, and Components; Safety and Security; Next Generation Systems; Heat Exchangers and Cooling Systems ◽

10.1115/icone20-power2012-54351 ◽

2012 ◽

Cited By ~ 2

Author(s):

Hiroyuki Sato ◽

Xing L. Yan ◽

Hirofumi Ohashi ◽

Yukio Tachibana ◽

Kazuhiko Kunitomi

Keyword(s):

Power Generation ◽

Gas Turbine ◽

Air Temperature ◽

Control Strategy ◽

System Analysis ◽

Ambient Air ◽

Outlet Temperature ◽

Generation Efficiency ◽

Ambient Air Temperature ◽

Dry Cooling

An original control strategy for very high temperature reactor (VHTR) gas-turbine system with dry cooling against ambient air temperature fluctuation was established in order to enable the freedom of site selection wherever desired without significant drawbacks on the performance. First, the operability of power conversion system and degradation of power generation efficiency were examined considering not only the thermodynamics but also the mechanical efficiency of compressor based on detailed performance map derived from experimental data. Second, control simulations for large ambient temperature fluctuations were conducted by system analysis code with the built-in control strategy. In addition, the sensitivity of power generation efficiency for typical steam cycle with dry cooling to ambient air temperature changes was assessed for the comparison. It was shown that the design goal can be effectively met simply by monitoring and controlling a few of key operating parameters such as reactor outlet temperature, primary coolant pressure. Furthermore, distinctive advantages of the VHTR gas-turbine system over nuclear power plant employing Rankine cycle was demonstrated when installing in inland area.

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(Performance of Gas Turbine Cooling System (Radiator) at PLTGU XYZ against Environmental Air Temperature)

R E M (Rekayasa Energi Manufaktur) Jurnal ◽

10.21070/r.e.m.v5i1.889 ◽

2021 ◽

Vol 5 (1) ◽

pp. 15-21

Author(s):

Ni Ketut Caturwati ◽

Yusvardi Yusuf ◽

Muhammad Ilham Al Faiz

Keyword(s):

Gas Turbine ◽

Air Temperature ◽

Cooling System ◽

Ambient Air ◽

Turbine Cooling ◽

Average Value ◽

Ambient Air Temperature ◽

Gas Turbine Cooling ◽

Environmental Air ◽

Operational Data

The heat exchanger is an important component in the gas and steam power plant (PLTGU) industry. One of the most important heat exchangers in gas turbine cooling systems is the gas turbine radiator. The gas turbine radiator functions to cool the cooling water, which circulated to various components of the gas turbine by using environmental air as the cooling medium. The purpose of this study was to determine the effect of environmental temperature on the performance of gas turbine radiators and to compare operational data in 2017 with operational data when the study conducted in 2019. Data collected for 3 days with 2-3 hour intervals. Data processing and analysis shows that the higher the ambient temperature, the higher the radiator effectiveness value. Data in 2017 shows the highest average value of effectiveness obtained at an ambient air temperature of 35 ˚C of 71,274%. Meanwhile, data in 2019 shows the highest average value of effectiveness at an ambient air temperature of 35 ˚C of 58,859%. Thus, the average effectiveness value of gas turbine radiators has decreased by 12,415% from 2017 to 2019

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Treatment of a Municipal Leachate Under Multi-Variable Conditions

Water Quality Research Journal ◽

10.2166/wqrj.1982.011 ◽

1982 ◽

Vol 17 (1) ◽

pp. 135-148

Author(s):

P.T. Wong ◽

D.S. Mavinic

Keyword(s):

Air Temperature ◽

Nutrient Loading ◽

Ambient Air ◽

Removal Rates ◽

Ambient Air Temperature

Abstract The treatability of a municipal leachate (BOD5 = 8090 mg/L) was investigated, by aerobic biostabilization, at a nutrient loading of BOD5:N:P of 100:3.2:1.1. The first stage effluents were subsequently polished by lime-magnesium coagulation. The ranges of ambient air temperature and sludge age studied were 5° to 25°C and 5 to 20 days, respectively. In the biostabilization phase, a BOD5:N:P loading of 100:3.2:1.1 was found to be “adequate” for treatment. Organic and metal removals in the first stage units were excellent. Under all conditions investigated, except for the two units close to washout conditions (5-day sludge age units at 5° and 10°C), BOD5 and COD removals of at least 99.4 and 96.4 percent, respectively, were achieved. Similarly, removal rates for most of the metals monitored were greater than 90 percent. In general, the removal of residual contaminants was not enhanced significantly by the addition of magnesium in the lime-magnesium polishing step.

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Ambient Air Temperature Assisted Crystallization for Inorganic CsPbI2Br Perovskite Solar Cells

Molecules ◽

10.3390/molecules26113398 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3398

Author(s):

Yi Long ◽

Kun Liu ◽

Yongli Zhang ◽

Wenzhe Li

Keyword(s):

Solar Cells ◽

Air Temperature ◽

High Performance ◽

Defect Density ◽

Perovskite Solar Cells ◽

Ambient Air ◽

Dark Phase ◽

High Quality ◽

Ambient Air Temperature ◽

Air Atmosphere

Inorganic cesium lead halide perovskites, as alternative light absorbers for organic–inorganic hybrid perovskite solar cells, have attracted more and more attention due to their superb thermal stability for photovoltaic applications. However, the humid air instability of CsPbI2Br perovskite solar cells (PSCs) hinders their further development. The optoelectronic properties of CsPbI2Br films are closely related to the quality of films, so preparing high-quality perovskite films is crucial for fabricating high-performance PSCs. For the first time, we demonstrate that the regulation of ambient temperature of the dry air in the glovebox is able to control the growth of CsPbI2Br crystals and further optimize the morphology of CsPbI2Br film. Through controlling the ambient air temperature assisted crystallization, high-quality CsPbI2Br films are obtained, with advantages such as larger crystalline grains, negligible crystal boundaries, absence of pinholes, lower defect density, and faster carrier mobility. Accordingly, the PSCs based on as-prepared CsPbI2Br film achieve a power conversion efficiency of 15.5% (the maximum stabilized power output of 15.02%). Moreover, the optimized CsPbI2Br films show excellent robustness against moisture and oxygen and maintain the photovoltaic dark phase after 3 h aging in an air atmosphere at room temperature and 35% relative humidity (R.H.). In comparison, the pristine films are completely converted to the yellow phase in 1.5 h.

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Evaluation of the influence of ambient air temperature and air velocity on mortar cement durability using a forced convection solar dryer

International Journal of Building Pathology and Adaptation ◽

10.1108/ijbpa-08-2020-0069 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Younes Bahammou ◽

Mounir Kouhila ◽

Haytem Moussaoui ◽

Hamza Lamsyehe ◽

Zakaria Tagnamas ◽

...

Keyword(s):

Environmental Factors ◽

Forced Convection ◽

Air Temperature ◽

Building Materials ◽

Ambient Air ◽

Physical Significance ◽

Drying Process ◽

Air Velocity ◽

Content Type ◽

Ambient Air Temperature

PurposeThis work aims to study the hydrothermal behavior of mortar cement toward certain environmental factors (ambient air temperature and air velocity) based on its drying kinetics data. The objective is to provide a better understanding and controlling the stability of mortar structures, which integrate the sorption phenomenon, drying process, air pressure and intrinsic characteristics. This leads to predict the comportment of mortar structures in relation with main environmental factors and minimize the risk of cracking mortar structures at an early age.Design/methodology/approachThermokinetic study was carried out in natural and forced convection solar drying at three temperatures 20, 30 and 40°C and three air velocities (1, 3 and 5 m.s-1). The empirical and semiempirical models tested successfully describe the drying kinetics of mortar. These models simulate the drying process of water absorbed by capillarity, which is the most common humidity transfer mechanism in building materials and contain parameters with physical significance, which integrate the effect of several environmental factors and intrinsic characteristics of mortar structures.FindingsThe models simulate the drying process of water absorbed by capillarity, which is the most common humidity transfer mechanism in building materials and contain parameters with physical significance, which integrate the effect of several environmental factors and intrinsic characteristics of mortar structures. The average activation energy obtained expressed the temperature effect on the mortar diffusivity. The drying constant and the diffusion coefficient can be used to predict the influence of these environmental factors on the drying behavior of various building materials and therefore on their durability.Originality/valueEvaluation of the effect of several environmental factors and intrinsic characteristics of mortar structures on their durability.

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Outdoor PM2.5, Ambient Air Temperature, and Asthma Symptoms in the Past 14 Days among Adults with Active Asthma

Environmental Health Perspectives ◽

10.1289/ehp92 ◽

2016 ◽

Vol 124 (12) ◽

pp. 1882-1890 ◽

Cited By ~ 33

Author(s):

Maria C. Mirabelli ◽

Ambarish Vaidyanathan ◽

W. Dana Flanders ◽

Xiaoting Qin ◽

Paul Garbe

Keyword(s):

Air Temperature ◽

Ambient Air ◽

The Past ◽

Asthma Symptoms ◽

Ambient Air Temperature

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EFFECTS OF LOW FLUCTUATING TEMPERATURES ON FARM ANIMALS.: III. INFLUENCE OF AMBIENT AIR TEMPERATURE ON FEED INTAKE OF LACTATING HOLSTEIN-FRIESIAN COWS

Canadian Journal of Animal Science ◽

10.4141/cjas58-022 ◽

1958 ◽

Vol 38 (2) ◽

pp. 148-159 ◽

Cited By ~ 10

Author(s):

M. A. MacDonald ◽

J. M. Bell

Keyword(s):

Milk Production ◽

Air Temperature ◽

Low Temperatures ◽

Ambient Air ◽

Feed Consumption ◽

Ambient Temperatures ◽

Ambient Air Temperature ◽

Holstein Friesian ◽

Cent Level ◽

Friesian Cows

This report presents effects of low temperatures on the feed consumption and efficiency of milk production of six mature, lactating, Holstein-Friesian cows that were confined in stanchions for three fortnightly experimental periods during which ambient temperatures measured in degree-hours per day (d-h/day) ranged from 110 to 1152 and daily minimum ambient air temperature (DMAAT) varied from 0° to 38°F. Applying results obtained, it was calculated that as temperatures decreased, i.e., d-h/day increased from 100 to 1200 and DMAAT decreased from 40° to 0°F, average daily intakes of total dry matter, hay, and gross and digestible Calories increased approximately 6.4 lb., 5.3 lb., 13 Therms and 9 Therms, respectively. Each of these increases was statistically significant at the 1 per cent level. Reductions in temperature also decreased gross and net caloric efficiencies of milk production approximately 10 and 8.5 per cent, respectively. These decreases were significant at the 2 per cent level. No correlation was evident between crude protein utilization and temperature.Results indicated that thermal stress was not overcome adequately by supplementary hay intake alone and that appetite stimulation by low temperatures had a carry-over effect continuing at least 24 hours. For continued efficient milk production during winters where low ambient temperatures are prevalent these results suggest it is necessary to provide some form of building insulation, ambient heat and/or provide a high energy supplement to otherwise adequate production rations.

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