Numerical simulation on cold water discharge of Nanshan LNG project in Longkou

The 3D physical model of the electrical water heater was built. The water-heater performance was resolved by computer fluid dynamics simulation (CFD). The heater performance is characterized by a new method rather than that the discharge efficiency, extraction efficiency and fraction of heat recoverable. The new method is based on the constant discharge water temperature and rate for end user, 5L/min and 43°C that include the hot water from EWH and cold water from outside EWH. But the water discharge rate from EWH was variable as the water temperature discharge from EWH was variable. Compared with the traditional method, it is more close to the user using reality condition.

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Numerical Simulation of Spring Water Discharge

Journal of Groundwater Hydrology ◽

10.5917/jagh1987.36.1 ◽

1994 ◽

Vol 36 (1) ◽

pp. 1-11

Author(s):

Masao OYAMA ◽

Akisato MIZUNO

Keyword(s):

Numerical Simulation ◽

Water Discharge ◽

Spring Water

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Influence of Water Sub-Cooling on Discharge Characteristics in a Water Storage Tank

10th International Conference on Nuclear Engineering, Volume 3 ◽

10.1115/icone10-22372 ◽

2002 ◽

Author(s):

Bingde Chen ◽

Haifeng Zheng ◽

Jie Li

Keyword(s):

Storage Tank ◽

Cold Water ◽

Water Discharge ◽

Water Storage ◽

Steam Condensation ◽

Discharge Characteristics ◽

Water Storage Tank ◽

Influence Of Water ◽

The Impact ◽

Limit Mode

The influences of water sub-cooling on water discharge behaviors from the water storage tank were studied experimentally with a test rig, which consists of a water vessel, a steam supplier, valves and piping. From this study, it is found that the gravitational discharging process is effected strongly by the steam condensation, taking place between steam and cold water in the vessel during discharge. Increased sub-cooling of the water, enhances the steam condensation, and promotes a deeper penetration of steam into water. The two modes of condensation identified in this study are: steam-supply-limit-mode and steam-condensation-limit-mode. The first mode occurs at the primary discharge period if water sub-cooling is large than a certain value, for example, 50°C sub-cooling in this study. Conclusions were derived based on this study for the impact of subcooling on discharge characteristics with respect to flow, pressure, and other parameters. Some suggestions to avoid or reduce undesired phenomena are also presented.

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A Nearshore Oceanic Front Induced By Wave Streaming

Journal of Physical Oceanography ◽

10.1175/jpo-d-21-0004.1 ◽

2021 ◽

Author(s):

Peng Wang ◽

James C. McWilliams ◽

Yusuke Uchiyama

Keyword(s):

Numerical Simulation ◽

Surface Wave ◽

Cold Water ◽

Wave Direction ◽

Offshore Water ◽

Inner Shelf ◽

Overturning Circulation ◽

Oceanic Front ◽

Continental Shelves ◽

Offshore Transport

AbstractCoastal fronts impact cross-shelf exchange of materials, such as plankton and nutrients, which are important to the ecosystems in continental shelves. Here using numerical simulation we demonstrate a nearshore front induced by wave streaming. Wave streaming is a bottom Eulerian current along the surface wave direction, and it is caused by the wave bottom dissipation. Wave streaming drives a Lagrangian overturning circulation in the inner shelf and pumps up deep and cold water into the overturning circulation. The water inside the overturning circulation is quickly mixed and cooled because of the wave streaming-enhanced viscosity. However, the offshore water outside the overturning circulation remains stratified and warmer. Hence, a front develops between the water inside and outside the overturning circulation. The front is unstable and generates submesoscale shelf eddies, which lead the offshore transport across the front. This study presents a new mechanism for coastal frontogenesis.

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Lithodynamic Processes along the Seashore in the Area of Planned Nuclear Power Plant Construction: A Case Study on Lubiatowo at Poland

Energies ◽

10.3390/en14061636 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1636

Author(s):

Piotr Szmytkiewicz ◽

Marek Szmytkiewicz ◽

Grzegorz Uścinowicz

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Cold Water ◽

Water Discharge ◽

Field Measurements ◽

Piping System ◽

Plant Construction ◽

Polish Government

The Polish government has made a decision to build a nuclear power plant (NPP) in the South Baltic coastal zone. This means that three major types of structures will be located in the nearshore: (1) breakwaters and a wharf where ships may dock to load and unload cargo (harbor), (2) seawalls protecting the shore against erosion and storm surge floods, and (3) an underwater piping system for cold water intake and heated water discharge. This study determines the dominant directions and rate of sediment transport for the coastline section in the vicinity of the projected Polish NPP (ca. 100,000 m3/year), as well as assesses current changes at this coastline location on the basis of field measurements and mathematical modeling.

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Regional ocean models indicate changing limits to biological invasions in the Bering Sea

ICES Journal of Marine Science ◽

10.1093/icesjms/fsaa014 ◽

2020 ◽

Vol 77 (3) ◽

pp. 964-974

Author(s):

A Droghini ◽

A S Fischbach ◽

J T Watson ◽

J P Reimer

Keyword(s):

Bering Sea ◽

Cold Water ◽

Water Discharge ◽

Adult Survival ◽

Indigenous Species ◽

The Us ◽

Survival And Reproduction ◽

Suitable Area ◽

Non Indigenous Species ◽

The Bering Sea

Abstract Minimal vessel traffic and cold water temperatures are believed to limit non-indigenous species (NIS) in high-latitude ecosystems. We evaluated whether suitable conditions exist in the Bering Sea for the survival and reproduction of NIS. We compiled temperature and salinity thresholds of NIS and compared these to ocean conditions projected during two study periods: recent (2003–2012) and mid-century (2030–2039). We also explored patterns of vessel traffic and connectivity for US Bering Sea ports. We found that the southeastern Bering Sea had suitable conditions for the year-round survival of 80% of NIS assessed (n = 42). This highly suitable area is home to the port of Dutch Harbor, which received the most vessel arrivals and ballast water discharge in the US Bering Sea. Conditions north of 58°N that include sub-zero winter water temperatures were unsuitable for most NIS. While mid-century models predicted a northward expansion of suitable conditions, conditions for reproduction remained marginal. Only 40% of NIS assessed (n = 25) had 6 or more weeks where conditions were suitable for reproduction. Our findings illustrate the potential vulnerability of a commercially important subarctic ecosystem and highlight the need to consider life stages beyond adult survival when evaluating limits to NIS establishment.

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Effect of Tail-Water of Water Source Heat Pumps on Lake Phytoplankton

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.726-731.1301 ◽

2013 ◽

Vol 726-731 ◽

pp. 1301-1304

Author(s):

Xiang Yang Huang ◽

Le Zhang

Keyword(s):

Heat Pump ◽

Population Distribution ◽

Cold Water ◽

Diversity Index ◽

Water Discharge ◽

Pump System ◽

Heat Pump System ◽

Discharge Point ◽

Tail Water

Taking water heat pump project in Kaixian Peoples Hospital of Chongqing City as a research example, by long-term monitoring on the lake temperature, nitrogen, phosphorus, and population distribution of algae, the effect of tail-water on phytoplankton of lake was studied. The results show that the tail-water have some influences on the number and diversity of algae in summer when the lake water heat pump system works, and the total number of algae near the tail-water discharge point is lower than that in other regions, but the dominant algae in different sampling points are same at the same time. In winter, cold water discharge makes the total number of algae near the tail-water discharge point essentially higher than that in other regions. Moreover, cold discharge water can reduce the diversity index of the lake phytoplankton. In addition, tail-water has a seasonal influence on lake phytoplankton, and its cumulative environmental impact can be obtained through monitoring and comparative research by long-term.

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Investigation of horizontal cold water discharge initial dilutions at various temperature differences using duckbill valve

Desalination and Water Treatment ◽

10.1080/19443994.2015.1022805 ◽

2015 ◽

Vol 57 (6) ◽

pp. 2437-2445 ◽

Cited By ~ 2

Author(s):

Naim Sezgin

Keyword(s):

Cold Water ◽

Water Discharge

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Heat Transfer Characteristics of Thermoelectric Generator System for Waste Heat Recovery from a Billet Casting Process: Experimental and Numerical Analysis

Energies ◽

10.3390/en14030601 ◽

2021 ◽

Vol 14 (3) ◽

pp. 601

Author(s):

Saurabh Yadav ◽

Jie Liu ◽

Man Sik Kong ◽

Young Gyoon Yoon ◽

Sung Chul Kim

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Thermoelectric Generator ◽

Cold Water ◽

Waste Heat ◽

Experimental Results ◽

Inlet Temperature ◽

Heat Transfer Characteristics ◽

One Dimensional ◽

Transfer Characteristics

In this study, experiments were performed to use the waste heat in a billet casting industry utilizing bismuth telluride thermoelectric generators (TEGs). Four d-type absorber plates made of copper were installed above the manufactured billet during the cooling process. Three sides of each absorber plate were attached to thermoelectric units. Therefore, a total of 12 units of the thermoelectric system were found to generate a power of 339 W. The power density of the TEG system was found to be 981 W/m2 while running the system at the operating voltage of the battery energy storage system (58 V). A one-dimensional numerical simulation was carried out using FloMASTERTM v9.1 (Mentor Graphics Corporation, Siemens, Dallas, TX, USA) to verify the experimental results, and the numerical results were found to exhibit good agreement with the experimental results. Furthermore, a one-dimensional numerical simulation was carried out to obtain the heat transfer characteristics at varying flow rates of cold water (Reynolds number = 2540–16,943) and at different inlet temperatures (10–25 °C) for the cold side of the TEG. The results indicate that the performance of the thermoelectric generator increases with an increase in the cold-water flow rate and a decrease in the inlet temperature of the cold water.

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