Thermal Effects of Power Plants on Lakes

1972 ◽  
Vol 94 (2) ◽  
pp. 163-168 ◽  
Author(s):  
F. K. Moore ◽  
Y. Jaluria
Keyword(s):  
Heat Flux ◽  
Power Plant ◽  
Power Plants ◽  
Constant Heat Flux ◽  
Critical Parameters ◽  
Cayuga Lake ◽  
Winter Temperatures ◽  
Diffusion Effects ◽  
Power Plant Cooling ◽  
And Diffusion

The natural thermal cycle of a stratified water body used for power-plant cooling will be disturbed both by heat addition and the mixing effect of withdrawal and return. A perturbation analysis for these effects is made with a model based on the assumption that a Richardson number is constant at the base of any stratified layer. On a further assumption about the profiles of wind-driven return currents, constant heat flux from that layer is inferred. This heat flux, and the diffusion coefficient at the thermocline, are the critical parameters of the simple one-dimensional line-segment model, and are chosen to give good imitation of the known natural cycle of Cayuga Lake. The model is then perturbed in terms of both heat flux and diffusion to give power-plant impact for that lake. Both transient and final cycle changes of summer and winter temperatures and stratification and overturn are calculated. It is shown that the heat and diffusion effects are comparable, and that the latter may be dominant if the discharge is diluted to meet a thermal standard. Certain implications as to strategy of water use are developed.

scholarly journals Using CO2 as a Cooling Fluid for Power Plants: A Novel Approach for CO2 Storage and Utilization

2021 ◽  
Vol 11 (11) ◽  
pp. 4974
Author(s):  
Tran X. Phuoc ◽  
Mehrdad Massoudi
Keyword(s):  
Power Plant ◽  
Power Plants ◽  
Saturated Vapor ◽  
Co2 Storage ◽  
Storage Container ◽  
Cooling Fluid ◽  
Capital Costs ◽  
Dry Air ◽  
Novel Approach ◽  
Power Plant Cooling

To our knowledge, the potential use of CO2 as a heat-transmitting fluid for cooling applications in power plants has not been explored very extensively. In this paper, we conduct a theoretical analysis to explore the use of CO2 as the heat transmission fluid. We evaluate and compare the thermophysical properties of both dry air and CO2 and perform a simple analysis on a steam-condensing device where steam flows through one of the flow paths and the cooling fluid (CO2 or air) is expanded from a high-pressure container and flows through the other. Sample calculations are carried out for a saturated-vapor steam at 0.008 MPa and 41.5 °C with the mass flow rate of 0.01 kg/s. The pressure of the storage container ranges from 1 to 5 MPa, and its temperature is kept at 35 °C. The pressure of the cooling fluid (CO2 or dry air) is set at 0.1 MPa. With air as the heat-removing fluid, the steam exits the condensing device as a vapor-liquid steam of 53% to 10% vapor for the container pressure of 1 to 5 MPa. With CO2 as the heat-removing fluid, the steam exits the device still containing 44% and 7% vapor for the container pressure of 1 MPa and 2 MPa, respectively. For the container pressure of 3 MPa and higher, the steam exits the device as a single-phase saturated liquid. Thus, due to its excellent Joule–Thomson cooling effect and heat capacity, CO2 is a better fluid for power plant cooling applications. The condensing surface area is also estimated, and the results show that when CO2 is used, the condensing surface is 50% to 60% less than that when dry air is used. This leads to significant reductions in the condenser size and the capital costs. A rough estimate of the amount of CO2 that can be stored and utilized is also carried out for a steam power plant which operates with steam with a temperature of 540 °C (813 K) and a pressure of 10 MPa at the turbine inlet and saturated-vapor steam at 0.008 MPa at the turbine outlet. The results indicate that if CO2 is used as a cooling fluid, CO2 emitted from a 1000 MW power plant during a period of 250 days could be stored and utilized.

Waste Heat Recovery and Saving Fresh Water Consumption in Power Plants

2012 ◽  
Author(s):  
Kwangkook Jeong
Keyword(s):  
Power Plant ◽  
Fresh Water ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Power Plants ◽  
Waste Heat ◽  
Combined Cycle ◽  
Water Recovery ◽  
Cooling Effects ◽  
Power Plant Cooling

A section to delineate ‘waste heat recovery’ has been written to contribute for the ASME Power Plant Cooling Specification/Decision-making Guide to be published in 2013. This paper informs tentative contents for the section on how to beneficially apply waste heat and water recovery technology into power plants. This paper describes waste heat recovery in power plant, current/innovative technologies, specifications, case study, combined cycle, thermal benefits, effects on system efficiency, economic and exergetic benefits. It also outlines water recovery technologies, benefits in fresh water consumptions, reducing acids emission, additional cooling effects, economic analysis and critical considerations.

scholarly journals THE WAVE PRESSING PLATE FOR PROTECTING COOLING WATERWAYS OF COASTAL POWER PLANTS

1984 ◽  
Vol 1 (19) ◽  
pp. 194 ◽  
Author(s):  
S.C. Chow ◽  
Frederick L.W. Tang ◽  
H.H. Hwung
Keyword(s):  
Power Plant ◽  
Water Surface ◽  
Nuclear Power ◽  
Power Plants ◽  
Wave Motion ◽  
Cooling Water ◽  
Northern Coast ◽  
Horizontal Plate ◽  
Hydraulics Laboratory ◽  
Power Plant Cooling

A horizontal plate laid on water surface to reduce the wave motion is proved to be effective theoretically and verified by model tests done at Tainan Hydraulics Laboratory. This principle has been put into practice on the northern coast of Taiwan for protecting a nuclear power plant cooling water intake against intruding waves. The design and construction of wave prevention works of such type are described succinctly in the paper. Also the effect of wave diminishing has been affirmed by measuring the respective waves heights outside and inside of the wave pressing plate.

scholarly journals Maintenance Strategy Optimization of a Coal-Fired Power Plant Cooling Tower through Generalized Stochastic Petri Nets

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1951 ◽  
Author(s):  
Arthur H.A. Melani ◽  
Carlos A. Murad ◽  
Adherbal Caminada Netto ◽  
Gilberto F.M. Souza ◽  
Silvio I. Nabeta
Keyword(s):  
Power Plant ◽  
Power Plants ◽  
Cooling Tower ◽  
Thermal Power ◽  
Stochastic Petri Nets ◽  
Optimal Size ◽  
Daunting Task ◽  
And Performance ◽  
The One ◽  
Power Plant Cooling

Determining the ideal size of maintenance staff is a daunting task, especially in the operation of large and complex mechanical systems such as thermal power plants. On the one hand, a significant investment in maintenance is necessary to maintain the availability of the system. On the other hand, it can significantly affect the profit of the plant. Several mathematical modeling techniques have been used in many different ways to predict and improve the availability and reliability of such systems. This work uses a modeling tool called generalized stochastic Petri net (GSPN) in a new way, aiming to determine the effect that the number of maintenance teams has on the availability and performance of a coal-fired power plant cooling tower. The results obtained through the model are confronted with a thermodynamic analysis of the cooling tower that shows the influence of this system’s performance on the efficiency of the power plant. Thus, it is possible to determine the optimal size of the repair team in order to maximize the plant’s performance with the least possible investment in maintenance personnel.

scholarly journals Study of the Characteristics of Wind over Nuclear Power Plants in Korea

2021 ◽  
Vol 21 (1) ◽  
pp. 57-70
Author(s):  
Su-Bin Oh ◽  
Chun-Ji Kim ◽  
Sang-Hyun Lee ◽  
Hyun-Ha Lee ◽  
Chun-Sil Jin ◽  
...  
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Protective Action ◽  
Radioactive Materials ◽  
Sea Breezes ◽  
Wind Characteristics ◽  
And Diffusion

To establish a strategy for public protective action from radioactive leakage in the event of Nuclear Power Plant (NPP) accidents, long-term records of wind data collected at the Korean NPPs were analyzed. Wind characteristics related to the advection and diffusion of radioactive pollutants were examined by analyzing the wind direction, speed, and land-sea breezes for NPPs (Hanbit, Hanul, Wolsong, Kori, and Shin-Kori) in Korea. The study also analyzed the characteristics of calm winds causing the accumulation of radioactive materials. The wind characteristics of each NPP differ depending on the seasonal and daily variabilities; thus, a detailed time-scaled airflow database is required. In addition, the findings, through continuous updates of the airflow database, will contribute to improving preparedness.

Value of Reservoir Storage for Resilient Power Plant Cooling and Basin-Wide Water Availability

2012 ◽  
Author(s):  
Ashlynn S. Stillwell ◽  
Michael E. Webber
Keyword(s):  
Power Plant ◽  
River Basin ◽  
Water Availability ◽  
Power Plants ◽  
Colorado River ◽  
Water Storage ◽  
River Basins ◽  
Reservoir Storage ◽  
Thermoelectric Power Plants ◽  
Power Plant Cooling

Since many thermoelectric power plants use water for cooling, the power sector is vulnerable to droughts, heat waves, and other water constraints. At the same time, large water demands for power generation can strain water availability for other users in a river basin. Opportunities exist for power plants to decrease freshwater demands, increasing both drought resiliency of power plants and water availability for other users in the basin. One particular method of decreasing freshwater demands for power plants is by incorporating reservoir storage into cooling operations. Using reservoir storage allows water to be recirculated and reused for power plant cooling, thereby decreasing water withdrawal requirements. Water storage also has the added benefit of making water available during times of shortage. While storage is known to be beneficial, no tools exist to explicitly quantify the basin-wide water availability impacts and increased power generation resiliency possible via constructing water storage at thermoelectric power plants without existing reservoirs. Here we present the results of modeling efforts regarding the value (both in terms of resiliency and water availability) of reservoir storage for power plant cooling and basin-wide water availability in the Brazos and Colorado River basins, using a customized river basin based-model along with existing Texas Water Availability Models. Results vary between river basins and different water availability models, with construction of new reservoirs generally increasing basin-wide water availability in the Brazos River basin and generally decreasing basin-wide water availability in the Colorado River basin. We conclude that the value of reservoir storage for power plant resiliency and basin-wide water availability is highly site-specific.

Critical parameters for the ignition of dust layers at constant heat flux boundary conditions

1994 ◽  
Vol 13 (4) ◽  
pp. 210-213 ◽  
Author(s):  
Willi Hensel ◽  
Ulrich Krause ◽  
Wolfgang John ◽  
Klaus Machnow
Keyword(s):  
Heat Flux ◽  
Boundary Conditions ◽  
Constant Heat Flux ◽  
Critical Parameters ◽  
Constant Heat ◽  
Flux Boundary Conditions

Rate of Sublimation of Ice by Radiative Heating in Freeze-Etching

1980 ◽  
Vol 38 ◽  
pp. 618-619
Author(s):  
Yeshayahu Talmon
Keyword(s):  
Heat Flux ◽  
Freeze Fracture ◽  
Constant Heat Flux ◽  
Radiative Heating ◽  
Constant Heat ◽  
Entire Sample ◽  
Simplified Method ◽  
Freeze Etching ◽  
Sublimation Rates ◽  
Fractured Surface

To bring out details in the fractured surface of a frozen sample in the freeze fracture/freeze-etch technique,the sample or part of it is warmed to enhance water sublimation.One way to do this is to raise the temperature of the entire sample to about -100°C to -90°C. In this case sublimation rates can be calculated by using plots such as Fig.1 (Talmon and Thomas),or by simplified formulae such as that given by Menold and Liittge. To achieve higher rates of sublimation without heating the entire sample a radiative heater can be used (Echlin et al.). In the present paper a simplified method for the calculation of the rates of sublimation under a constant heat flux F [W/m2] at the surface of the sample from a heater placed directly above the sample is described.

Fuzzy multi-objective decision making approach for nuclear power plant installation

2020 ◽  
Vol 39 (5) ◽  
pp. 6339-6350
Author(s):  
Esra Çakır ◽  
Ziya Ulukan
Keyword(s):  
Linear Programming ◽  
Power Plant ◽  
Nuclear Power Plant ◽  
Energy Supply ◽  
Energy Demand ◽  
Nuclear Power ◽  
Power Plants ◽  
Total Duration ◽  
Objective Functions ◽  
Multi Objective

Due to the increase in energy demand, many countries suffer from energy poverty because of insufficient and expensive energy supply. Plans to use alternative power like nuclear power for electricity generation are being revived among developing countries. Decisions for installation of power plants need to be based on careful assessment of future energy supply and demand, economic and financial implications and requirements for technology transfer. Since the problem involves many vague parameters, a fuzzy model should be an appropriate approach for dealing with this problem. This study develops a Fuzzy Multi-Objective Linear Programming (FMOLP) model for solving the nuclear power plant installation problem in fuzzy environment. FMOLP approach is recommended for cases where the objective functions are imprecise and can only be stated within a certain threshold level. The proposed model attempts to minimize total duration time, total cost and maximize the total crash time of the installation project. By using FMOLP, the weighted additive technique can also be applied in order to transform the model into Fuzzy Multiple Weighted-Objective Linear Programming (FMWOLP) to control the objective values such that all decision makers target on each criterion can be met. The optimum solution with the achievement level for both of the models (FMOLP and FMWOLP) are compared with each other. FMWOLP results in better performance as the overall degree of satisfaction depends on the weight given to the objective functions. A numerical example demonstrates the feasibility of applying the proposed models to nuclear power plant installation problem.

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