Inlet Air Supercharging of a 70 kW Microturbine

The significant reduction in power output of small gas turbines at high ambient temperatures places the technology at a significant disadvantage compared with reciprocating engines. On site power applications in many jurisdictions are experiencing high power costs during summer peak times. A variable speed industrial fan combined with an evaporative cooler has been constructed and operated in the CETC laboratory in Ottawa, Canada to supply supercharged inlet air to a microturbine rated at 70 kW at ISO conditions. The supercharging system can raise the inlet air pressure by 10.5 kPa (42” wc). A mapping of the turbine performance has been done as a function of boost pressure, relative humidity and ambient air temperature. A net power increase has been observed from 57 kW to 70 kW at an ambient air temperature of 33°C (91°F) and RH of 60%, a 23% increase. Supercharging at lower temperatures yields lower net power increases since the microturbine generator rating is the limiting factor; for example an 11% increase in net power was observed at an inlet air temperature of 11°C (52°F) and RH of 60%. Supercharging was shown to decrease net fuel-to-electricity efficiency of this recuperated turbine by about 3%, at an air temperature of 33°C (91°F). An economic analysis using published power prices and weather data from Toronto explores the business case of using supercharging, with the best economies likely for multiple units or larger microturbines, such as 250 kW units. The objective of the project was to demonstrate the concept leading to a field trial in Toronto or in Calgary where the altitude offers a further benefit to the inlet air supercharging concept. Work is underway to design a control system suitable for field deployment for the concept.

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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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Energy performance analysis of GE-F5 gas turbines at off-design conditions by applying an innovative convergent–divergent system for the inlet air cooling

Measurement and Control ◽

10.1177/0020294019877504 ◽

2019 ◽

Vol 52 (9-10) ◽

pp. 1508-1516

Author(s):

Seyed Mehdi Arabi ◽

Hossein Ghadamian ◽

Mohammad Aminy ◽

Hassan Ali Ozgoli ◽

Behzad Ahmadi ◽

...

Keyword(s):

Output Power ◽

Air Temperature ◽

Gas Turbines ◽

Power Plants ◽

Characteristic Curve ◽

Ambient Air ◽

Energy Performance ◽

Air Cooling ◽

Design Algorithm ◽

Ambient Air Temperature

Ambient air temperature increase, in a gas power plant, causes the intake air mass flow rate to be decreased and can have a significant reducing effect on output power and efficiency. To compensate for this reduction, at different climate conditions, various systems can be used to cool the inlet air. To predict the performance of a gas turbine at off-design conditions (by changing surrounding conditions and/or the air cooling method), modeling of the unit performance is required. Due to the high consumption of water and electricity in the conventional cooling systems, in this paper, in addition to introducing an off-design algorithm, governing equations of each cycle elements were inferenced by their characteristic curve. By developing code in MATLAB software, the effect of applying a novel convergent–divergent system on GE-F5 gas units in Yazd Zanbagh power plants was studied. The results show that in a temperature range between 14 and 50 °C, for each degree decrease in ambient air temperature, an approximately 8.99 kW increase in output power can be obtained. The main advantage of this system is the capability of its application in both dry and humid regions. In addition, the refrigerant medium is not required, which makes this system desirable to use in arid areas.

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Long-Term Weather Data Measurements From A Danish Climate Station And The Weather’s Influence On The Thermal Performance Of Solar Collectors

Slovak Journal of Civil Engineering ◽

10.1515/sjce-2015-0009 ◽

2015 ◽

Vol 23 (2) ◽

pp. 23-29

Author(s):

Lukáš Skalík

Keyword(s):

Air Temperature ◽

Thermal Performance ◽

Global Radiation ◽

Diffuse Radiation ◽

Ambient Air ◽

Energy Output ◽

Weather Data ◽

Solar Collectors ◽

Ambient Air Temperature ◽

Climate Station

Abstract A weather data evaluation from a climate station in Lyngby, Denmark, was carried out. Twenty years of measurements show that the increase in global radiation was almost 3.5 kWh/m2 per year, corresponding to a growth of the yearly global radiation of 7 % for the last 20 years. The global radiation variation between the least sunny year to the sunniest year was 20%. The increase in diffuse radiation was 1.9 kWh/m2 per year, corresponding to 20 years’ growth of up to 7 %. The annual diffuse radiation of nearly 19 % varied from the least cloudy year to the cloudiest year. A small increase was measured for the ambient air temperature. The measurements showed a yearly increase of 0.04 K per year. The average yearly ambient air temperature variation from the coldest to the warmest year was 3.1 K. According to the seasonal growth of the parameters measured, the ambient air temperature and diffuse radiation increased the most in the summer period, while the global radiation significantly increased in the spring months. The calculations of the solar collector's thermal performance in Lyngby showed that the energy output was mostly dependent on beam radiation. The ambient air temperature did not have a high influence on the thermal performance of the solar collectors compared to the influence of the total solar radiation.

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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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Associations between ambient air temperature, low birth weight and small for gestational age in term neonates in southern Israel

Environmental Health ◽

10.1186/s12940-018-0420-z ◽

2018 ◽

Vol 17 (1) ◽

Cited By ~ 8

Author(s):

Itai Kloog ◽

Lena Novack ◽

Offer Erez ◽

Allan C. Just ◽

Raanan Raz

Keyword(s):

Birth Weight ◽

Low Birth Weight ◽

Air Temperature ◽

Gestational Age ◽

Small For Gestational Age ◽

Ambient Air ◽

Term Neonates ◽

Ambient Air Temperature

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Research On Solar Energy Collector With Cell Polycarbonate Absorber

Environment Technology Resources Proceedings of the International Scientific and Practical Conference ◽

10.17770/etr2011vol1.914 ◽

2015 ◽

Vol 1 ◽

pp. 213

Author(s):

Henriks Putāns ◽

Viktorija Zagorska ◽

Imants Ziemelis ◽

Zanis Jesko

Keyword(s):

Experimental Investigation ◽

Solar Radiation ◽

Air Temperature ◽

Heat Carrier ◽

Heat Insulation ◽

Ambient Air ◽

Maximum Temperature ◽

Experimental Examination ◽

Ambient Air Temperature ◽

Flat Plate Solar Collector

A flat plate solar collector with cell polycarbonate absorber and transparent cover has been made and its experimental investigation carried out. The collector consists of a wooden box, into which, a layer of heat insulation with a mirror film and 4 mm thick cell polycarbonate sheet, as the absorber, are placed. The coherence between collector’s efficiency, heat carrier and ambient air temperature, as well as intensity of the solar radiation and heat power in the experimental investigation has been obtained. During the experimental examination the maximum temperature of the heat carrier reached 80˚C at the intensity of solar radiation about 0.8 kW/m2 and ambient air temperature around 32˚C. The efficiency of the collector reached 33-60%, depending on the intensity of solar radiation and surrounding air temperature.

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