scholarly journals SIMILARITY CONDITIONS FOR THERMAL-HYDRAULIC MODEL TESTS OF TIDAL ESTUARIES

1974 ◽  
Vol 1 (14) ◽  
pp. 142
Author(s):  
Gerd Flugge ◽  
Horst Schwarze
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Water Discharge ◽  
Free Surface Flow ◽  
Hydraulic Model ◽  
Surface Flow ◽  
Hot Water ◽  
Hydraulic Models ◽  
Tidal Estuaries ◽  
Dynamic Similitude

In connection with the design of proposed nuclear power plants on the Lower Weser River and on the Lower Elbe River in Germany, tidal models were constructed and tests carried out at the Franzius-Institute of the Technical University of Hannover for the purpose of studying the mixing and spreading of the hot water discharge. Thermal-hydraulic models are today still the most reliable method for the prediction of temperature distributions in the total area of temperature increase, especially in tidal regions. Hydraulic models with free surface flow are in general based on the FROUDE scaling lav;. The flow fields in both the hydraulic model and in the prototype show a dynamic similitude when the FROUDE numbers of the flow in the model and in the nature are equal at corresponding points.

An Efficient, Flexible Arrangement to Generate High Quality Process or Domestic Heat in Recuperative Gas Cycle Power Plants: Application to Helium Direct Cycle Nuclear Power Plants

1979 ◽  
Vol 101 (1) ◽  
pp. 130-140 ◽  
Author(s):  
Z. P. Tilliette ◽  
B. Pierre ◽  
P. F. Jude
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Hot Water ◽  
Primary Circuit ◽  
Inlet Temperature ◽  
Total Efficiency ◽  
High Quality ◽  
Quality Process ◽  
Direct Cycle

The advantages of gas turbine power plants in general and closed cycle systems under gas pressure in particular for waste heat recovery are well known. A satisfactory efficiency for electric power generation and good conditions to obtain a significant amount of hot water above 100°C lead to a high fuel utilization. However, as in most of projects, it is not much possible to produce high temperature steam or water without significantly decreasing the electricity production. A new method for an additional generation of high quality process or domestic heat is proposed. The basic feature of this method lies in arranging one or two steam generators or preheaters in parallel with the low pressure side of the recuperator. The high total efficiency and the noteworthy flexibility of this system are emphasized. This arrangement is suitable for any kind of heat source, but the applications presented in this paper are related to helium direct cycle nuclear power plants the main features of which are a single 600 MW(e) turbomachine, a turbine inlet temperature of 775°C, no or one intermediate cooling and a primary circuit fully integrated in a pre-stressed concrete reactor vessel.

scholarly journals ADAPTABILITY OF PREDICTION METHOD OF HYDRAULIC MODEL EXPERIMENT FOR THERMAL DIFFUSION

1976 ◽  
Vol 1 (15) ◽  
pp. 175 ◽  
Author(s):  
Masanobu Kato ◽  
Akira Wang
Keyword(s):  
Heat Exchange ◽  
Nuclear Power ◽  
Water Discharge ◽  
Cooling Water ◽  
Prediction Method ◽  
Hydraulic Model ◽  
Surface Heat ◽  
Horizontal Scale ◽  
Vertical Scale ◽  
Surface Heat Exchange

In formation processes of the region of water temperature rise caused by the cooling water discharge from thermal and nuclear power stations located on the site facing the ocean, flow of discharged cooling water itself, current and turbulence existing in the sea region play an important role. Their motions are predominant in the horizontal direction in the sea region. The horizontal scale of thermal extent is, therefore, extremely larger than the vertical scale of thermal extent. Therefore, whenever the diffusion experiments of discharged warm water in the far field are conducted by hydraulic model method, the model which has a difference in the geometrical reduced rate between the horizontal and vertical directions, what is called, the distorted model must be used, so that the effects of the viscosity and the surface tension on the experimental model can be avoided. In such a model, the horizontal scale is determined by the relation between the size of the experimental water basin and the surface area of the sea region to be reproduced. But, there is no clear method of choosing the vertical scale, though there are some suggestions about it. For example, the similarity of the 4/3 power law of the diffusion coefficient gives a relation between the vertical scale and the horizontal scale of the hydraulic model. On the other hand, the similarity of the surface heat exchange coefficient gives another relation between the vertical scale and the horizontal scale of hydraulic model if the surface heat exchange coefficients of hydraulic model and prototype are not same. Therefore, it is better to give some allowance in the determination of the vertical scale of the hydraulic model within the range where the reproducibility of the diffusion phenomena can be conserved.

scholarly journals THERMAL DISCHARGES: PROTOTYPE vs. HYDRAULIC MODEL

1976 ◽  
Vol 1 (15) ◽  
pp. 173
Author(s):  
Gary C. Parker ◽  
C.S. Fang ◽  
Albert Y. Kuo
Keyword(s):  
Nuclear Power ◽  
Water Discharge ◽  
Cooling Water ◽  
Hydraulic Model ◽  
Physical Parameters ◽  
Thermal Discharge ◽  
James River ◽  
Model Experiments ◽  
Model Predictions ◽  
Physical Effects

Data on physical parameters in the James River around the condenser cooling water discharge of the Surry Nuclear Power Plant, taken prior to and during plant operation, were analyzed to determine the physical effects of the thermal discharge on the area and to compare the prototype distribution of excess temperature to predictions based on hydraulic model experiments. The results of this investigation indicated that the increase in water temperatures due to the thermal discharge did not represent a significant alteration of the physical environment outside the mixing zone. The thermal discharge experienced turbulent mixing and entrainment near the outfall and temperatures decreased rapidly in this region. Field data on temperature distributions around the discharge, when compared to predictions based on hydraulic model experiments, indicate that the model predictions were conservative.

scholarly journals Studi Numerik Perbandingan Kinerja dan Medan Aliran Turbin Vortex Gravitasi dengan Tipe Sudu Lengkung Backward dan Forward

2021 ◽  
Vol 16 (1) ◽  
pp. 48
Author(s):  
Didit Setyo Pamuji ◽  
Harry Laksono Nugroho ◽  
Daru Sugati
Keyword(s):  
Numerical Simulation ◽  
Power Plants ◽  
Vortex Flow ◽  
Turbine Blades ◽  
Free Surface Flow ◽  
Surface Flow ◽  
Hydro Power ◽  
Curved Blade ◽  
Hydro Power Plants ◽  
Produce Flow

<p><em>The interaction of turbine blades with vortex flow in micro-hydro power plants based on gravity vortex is still not clearly clarified, therefore numerical simulation is a tool to produce flow visualization that helps analyze the performance of experimental results. This study aims to compare the performance of a gravity vortex flow power generator using a conical basin with a </em><em>inclined</em><em> backward and </em><em>inclined </em><em>forward blade design using a numerical simulation approach. The simulation begins by validating the results of torque performance and visualizing the flow of experimental research conducted by previous researchers, then the simulation settings are used to compare the performance of the </em><em>inclined</em><em> backward and </em><em>inclined </em><em>forward blade turbine designs with variations in turbine rotation speed of 80, 120, 160 and 180 rpm. The simulation results show that the curved backward blade performance is better than the forward curved blade which is supported by visualizing the free surface flow and static pressure contours on the blade surface.</em><em></em></p>

scholarly journals Application of Zoo/plankton Indicators for Assessment of the Nuclear Power Plants Impact upon Cooling Pools

2020 ◽  
pp. 107-125
Author(s):  
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Water Discharge ◽  
Water Area ◽  
Species Number ◽  
Zooplankton Abundance ◽  
The Baltic

The article discusses the outcomes of the researches of zoo/plankton of various type nuclear power plants cooling pools located in different in terms of hyd ro g r aph ic c h a r ac t e r i s t ic s a nd z o opl a n k t on s t r uc t u re c at c h ment b a s i n s . I n Kop or ye B ay, a part of the Bay of Finland water area, discharge of warmed waters of Leningrad Nuclear Power Plant caused the decrease of plankton invertebrates’ quantitative indicators. In the Beloyarsk Nuclear Power Plant cooling pool warming in the most cases was favorable for the zooplankton abundance and biomass increase. In both researched reser voirs the warm water discharge resulted in the decrease of the total species number in the communities. The Neman River (the Baltic Nuclear Power Plant designed receiver for waste waters) in the period of the research was not affected by the nuclear plant impact. As a whole, for this water course water area ma ximal values of zooplankton abundance and biomass have been registered during spring periods while their decrease has been observed in summer and autumn. The most degree of trophity was noted near towns of Grodno, Kaunas, Yurbarkas and Neman.

Large, Flexible, Efficient, 750°C Closed Gas Cycle Coal-Fired or Nuclear Cogeneration Plants

1980 ◽  
Author(s):  
Z. P. Tilliette ◽  
B. Pierre
Keyword(s):  
Gas Turbine ◽  
Nuclear Power ◽  
Power Plants ◽  
Hot Water ◽  
Inlet Temperature ◽  
Oil Consumption ◽  
Turbine Inlet Temperature ◽  
Pressure Steam ◽  
Conversion Coefficients ◽  
Steam Superheating

A now unavoidable concern is the best possible use of a given energy source in order to meet the demand of power and heat. The most efficient, rational, thermodynamically satisfactory way of producing heat is to cogenerate it with power and to handle it as a by-product. Another basic condition is to supply heat without disturbing the operation of main turbogenerators. Closed helium cycle, non-intercooled, gas turbine coal-fired and nuclear power plants which meet these requirements are presented in this paper. Low-pressure steam and hot water are recovered from the precooler; medium, high pressure steam and steam superheating are generated by means of a bypass arrangement of the recuperator. The concept offers attractive overall energy conversion coefficients, very flexible heat production conditions and significant potentialities of reducing oil consumption. Results are given for the conservative 750 C gas turbine inlet temperature.

Advancements In Hydraulic Modeling of Cooling Water Intakes in Power Plants

2005 ◽  
Author(s):  
Andrew E. Johansson ◽  
Philip S. Stacy ◽  
Dean K. White ◽  
Fangbiao Lin
Keyword(s):  
Power Plants ◽  
Cooling Water ◽  
Hydraulic Modeling ◽  
Hydraulic Performance ◽  
Hydraulic Model ◽  
Flow Conditions ◽  
Acceptance Criteria ◽  
Hydraulic Models ◽  
Model Studies ◽  
Service Water

Satisfactory hydraulic performance of pump intakes is very important to avoid flow conditions that would adversely affect the performance of cooling water and service water pumps in power plants. Hydraulic performance is best evaluated using physical hydraulic models. Typically, a hydraulic model is used to identify formation of any objectionable free surface and subsurface vortices, presence of any high swirl or pre-rotation and/or non-uniform axial velocity distribution at the impeller entrance. A model study would evaluate an initial design based on an acceptance criteria and derive remedial modifications as needed to meet the acceptance criteria. Over the past several years, modeling of pump intakes has evolved in terms of criteria for model scale selection, instrumentation accuracy and computerized data acquisition techniques, the use of computational fluid dynamics (CFD) to evaluate detailed approach flow patterns and the availability of Hydraulic Institute Standards (HIS) for acceptance criteria to evaluate hydraulic performance. Also, hydraulic model studies conducted by various laboratories over many years have contributed to the advancement of the knowledge about vortex formation, swirl and scale effects in models. To the benefit of all, these advancements have resulted in higher confidence in models with more efficient execution of the model studies at minimal costs. The purpose of this paper is to present advancements that have been made in the field of hydraulic modeling of pump intakes. Examples are provided to show how hydraulic models may be used to first identify unacceptable flow conditions and then to derive modifications to improve the hydraulic performance for both circulating water and cooling water pump intakes.

Research on the Law of Thermal Effect of Floating Nuclear Power Plants Thermal Discharge

2015 ◽  
Vol 799-800 ◽  
pp. 734-738
Author(s):  
Tian Qi Dai ◽  
Shi Wei Yao ◽  
Zhi Guo Wei
Keyword(s):  
Thermal Effect ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Water Discharge ◽  
Cooling Water ◽  
Cross Flow ◽  
Pollution Prevention ◽  
Thermal Pollution ◽  
Thermal Discharge

The waste heat emissions of thermal discharge from floating nuclear power plants may have a negative thermal effect on the environment. Study on the dilution and diffusion of cooling water plays an important role in thermal pollution prevention. The cooling water discharge process can be condensed into the thermal jet in cross flow. According to the theory of computational fluid dynamics, the mathematical model of round horizontal thermal jets in cross flow is established. The 3D numerical simulation of thermal jets based on finite volume method is achieved by using the Realizable k-ε turbulence model and the Semi-implicit method for pressure linked equations, and the three-dimensional trajectory of thermal jet are obtained. The rationality of analysis method is approved by comparing calculation value with experimental value. The temperature distributions in thermal jets are studied through the numerical experiments conducted under different cross-flow velocity and different emission angle. As a result, the impacts of these conditions on thermal pollution area are found, and the theoretic bases are provided for the design of the cooling water discharge pipe.

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