Academic literature on the topic 'Circulating water temperature'
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Journal articles on the topic "Circulating water temperature"
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Song, Xun Cheng, Xiao Long Xu, Sha Sha Hu, and Zhi Chuan Guan. "Full Transient Features of Heat Transfer and Sensitivities on Deep Water Wells." Advanced Materials Research 524-527 (May 2012): 1423–28. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.1423.
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Wellbore temperature is significant to well program and safety drilling for deep water drilling operations. On the basis of transient heat transfer mechanisms involved in deep water drilling among wellbore and formation and sea water, wellbore temperature profile, especially near sea bed and sensitivities to drilling fluid circulating duration, inlet temperature, water depth, water temperature, riser insulation and drilling fluid specific heat capacity have been analyzed via this model. Analysis show that deep-water wellbore temperature is much lower than a land well, the temperatures above sea bed normally ranges 10-30°C, and decreases with increased circulating duration; temperature at both outlet and bottom hole decreases drastically with increased water depth, and heat generation must be considered into estimating wellbore temperature profile especially one at bottom hole.
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Xi, Xinming, Shixiong An, Lei Xu, Xiaoze Du, Huimin Wei, and Hongchen Sun. "Suitable Analysis of Micro-Increased Capacity Model on Cold-End System of Nuclear Power Plant." Energies 16, no. 20 (2023): 7188. http://dx.doi.org/10.3390/en16207188.
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The cold-end system of a nuclear power plant is a key complex node connecting the power generation system with the variable environmental conditions, and its operation, economy, and stability have become the main obstacles to further improving the performance of the first and second circuits. The current research on the interactions between the cold-end system and the thermal cycle of nuclear power mainly adopts the micropower model, while the existing condenser model does not take into account the influence of the turbine exhaust resistance and exhaust flow and other factors on the condenser vacuum change caused by the change in the circulating water flow rate and temperature in determining the optimal vacuum. This ignores the interactions between the equipment and the interconnections between the parameters, which results in the reduction of the model’s accuracy. This paper takes a nuclear power unit as an example, adopts the “constant flow calculation” method to calculate the heat balance of the two-loop thermal system of the nuclear power plant, and constructs an integrated simulation model of the reaction environment variables, the cold-end system, and the thermal cycle. Taking the circulating water temperature and flow rate as variables, the errors of the separate condenser model and the coupled model in circulating water parameter changes were obtained under the condition of satisfying the thermal system operation, and the circulating water temperature and flow rate change ranges applied by the separate condenser model were analyzed in order to reduce the amount of calculations when the unit power error was 1%. The results show that the circulating water temperature is 4 °C, the applicable range of the circulating water flow rate is 42 m3/s to the rated flow rate, the applicable range of the circulating water temperature is 20 °C, the applicable range of the circulating water flow rate is 32.12 m3/s to the rated flow rate, the applicable range of the circulating water temperature is 26 °C, the applicable range of the circulating water flow rate is 38.63 m3/s to the rated flow rate, the applicable range of the circulating water temperature is 30 °C, and the applicable range of the circulating water flow rate is 45 m3/s to the rated flow rate. At a circulating water temperature of 26 °C, the applicable range of the circulating water flow is between 38.63 m3/s and the rated flow; at a circulating water temperature of 30 °C, the applicable range of the circulating water flow is between 45.64 m3/s and the rated flow.
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Lv, Jing, and Jie Yang. "Designing and Researching of Gas Cooler in Trans-Critical Carbon Dioxide Water Heater." Advanced Materials Research 171-172 (December 2010): 368–73. http://dx.doi.org/10.4028/www.scientific.net/amr.171-172.368.
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In this paper a gas cooler for trans-critical carbon dioxide water heater was designed and calculated according to the theory basis for the optimal design. The characteristic parameters of gas cooler in heat pump hot water system were compared and analyzed, applying the data from trans-critical carbon dioxide water heater test bed, under one-time heating condition, by different flow of chilled water and hot water, different inlet temperatures of chilled water and hot water. To sum up, coefficient of performance can be increased by increasing the chilled water inlet temperature or hot water circulating flow, while it can be decreased by increasing the inlet temperature of hot water circulating system，the parameters (flow of water, inlet temperature, the refrigerant mass flow, gas cooler pressure and inlet temperature of refrigerant) need to be adjusted to different requirements, for ensuring the high efficiency of system.
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Taguchi, Akiko, Jebadurai Ratnaraj, Barbara Kabon, et al. "Effects of a Circulating-water Garment and Forced-air Warming on Body Heat Content and Core Temperature." Anesthesiology 100, no. 5 (2004): 1058–64. http://dx.doi.org/10.1097/00000542-200405000-00005.
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Background Forced-air warming is sometimes unable to maintain perioperative normothermia. Therefore, the authors compared heat transfer, regional heat distribution, and core rewarming of forced-air warming with a novel circulating-water garment. Methods Nine volunteers were each evaluated on two randomly ordered study days. They were anesthetized and cooled to a core temperature near 34 degrees C. The volunteers were subsequently warmed for 2.5 h with either a circulating-water garment or a forced-air cover. Overall, heat balance was determined from the difference between cutaneous heat loss (thermal flux transducers) and metabolic heat production (oxygen consumption). Average arm and leg (peripheral) tissue temperatures were determined from 18 intramuscular needle thermocouples, 15 skin thermal flux transducers, and "deep" hand and foot thermometers. Results Heat production (approximately 60 kcal/h) and loss (approximately 45 kcal/h) were similar with each treatment before warming. The increases in heat transfer across anterior portions of the skin surface were similar with each warming system (approximately 65 kcal/h). Forced-air warming had no effect on posterior heat transfer, whereas circulating-water transferred 21+/-9 kcal/h through the posterior skin surface after a half hour of warming. Over 2.5 h, circulating water thus increased body heat content 56% more than forced air. Core temperatures thus increased faster than with circulating water than forced air, especially during the first hour, with the result that core temperature was 1.1 degrees +/- 0.7 degrees C greater after 2.5 h (P < 0.001). Peripheral tissue heat content increased twice as much as core heat content with each device, but the core-to-peripheral tissue temperature gradient remained positive throughout the study. Conclusions The circulating-water system transferred more heat than forced air, with the difference resulting largely from posterior heating. Circulating water rewarmed patients 0.4 degrees C/h faster than forced air. A substantial peripheral-to-core tissue temperature gradient with each device indicated that peripheral tissues insulated the core, thus slowing heat transfer.
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Wang, Zhonghua, Zenggang Yue, Wei Wang, et al. "Study on the Influence of Circulating Water Bypass on the Thermal and Anti-Freezing Characteristics of High-Level Wet Cooling Tower." Energies 17, no. 9 (2024): 2073. http://dx.doi.org/10.3390/en17092073.
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When heating units are operated in winter, the extreme conditions, such as deep peak regulation and large extraction, can easily lead to a low unit load and severe icing in the wet cooling tower, which threatens the safe operation of the unit. Therefore, it is necessary to study the anti-freezing characteristics of the wet cooling tower. In this paper, a three-dimensional numerical model of a high-level, natural draft wet cooling tower is developed based on the constant heat load method. The influence of withdrawing a certain percentage of circulating water into the bypass on the cooling performance and anti-freezing characteristics of the high-level, natural draft wet cooling tower is investigated. The results show that as the percentage of circulating water bypass extraction increases, the temperature drop of circulating water in the tower continues to increase, but the lowest and the average water temperatures at the bottom of the packing continue to decrease. At the same time, the amount of circulating water entering the tower decreases, the pressure difference between the inside and outside of the tower under the same environmental conditions decreases, and the pumping force of the cooling tower decreases. If the circulating water bypass extraction percentage is less than 10%, it can prevent the circulating water from freezing at the bottom of the packing and, at the same time, try to reduce the temperature of the circulating water entering the condenser to ensure the efficiency of the unit.
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Sanaev, Shokhzodbek Sobirovich, Mukhiddin Chorievich Tursunov, and Javokhir Ibrokhim ogli Botirov. "IMPROVING THE CIRCULATING WATER COOLING DEVICE IN THE INDUSTRIAL ENTERPRISE." Modern Scientific Research International Scientific Journal 1, no. 7 (2023): 206–12. https://doi.org/10.5281/zenodo.10031944.
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Currently, cooling systems with cooling tower are quite common (up to 70%). In them, water is used repeatedly, but part of the water is lost when it evaporates, and therefore it will be necessary to maintain the system regularly with clean water. Cooling tower circulating water partially evaporates and convection, that is, a decrease in temperature due to heat exchange with air. Further the economic feasibility of having additional cooling tower capacity to allow for economizer cooling, in light of reduced tower capacity at lower temperatures [3] is investigated. Creating rational water use schemes and reducing the consumption of fresh water taken from water supply systems or natural reservoirs can be a significant factor in improving the economic performance of the enterprise. The basis of rational water use schemes are water-circulation cooling systems, where cooling towers are used as cooling equipment.
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Lv, Ziqiang, Jiuju Cai, Wenqiang Sun, and Lianyong Wang. "Analysis and Optimization of Open Circulating Cooling Water System." Water 10, no. 11 (2018): 1592. http://dx.doi.org/10.3390/w10111592.
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Open circulating cooling water system is widely used in process industry. For a system with a fixed structure, the water consumption and blowdown usually change with the varying parameters such as quality and temperature. With the purpose of water saving, it is very important to optimize the operation strategy of water systems. Considering the factors including evaporation, leakage, blowdown and heat transfer, the mass and energy conservation equations of water system are established. On this basis, the quality and temperature models of makeup and blowdown water are, respectively, developed. The water consumption and discharge profiles and the optimal operating strategy of the open recirculating cooling water system under different conditions are obtained. The concept of cycles of temperature is proposed to evaluate the temperature relationship of various parts of the open circulating cooling water system. A mathematical relationship is established to analyze the influence of the water temperature on the makeup water rate of the system under the condition of insufficient cooling capacity of the cooling tower. In addition, the co-influences of quality and temperature parameters on the system are analyzed.
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Li, Zhi Wei, Hong Zhou He, and Huang Huang Zhuang. "Experimental Study on Compact External Heat Exchanger for a 4 MWth Circulating Fluidized Bed Combustor." Applied Mechanics and Materials 448-453 (October 2013): 3259–69. http://dx.doi.org/10.4028/www.scientific.net/amm.448-453.3259.
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The characteristics of the external heat exchanger (EHE) for a 4 MWth circulation fluidized bed combustor were studied in the present paper. The length, width and height of EHE were 1.5 m, 0.8 m and 9 m, respectively. The circulating ash flow passing the heating surface bed could be controlled by adjusting the fluidizing air flow and the heating transferred from the circulating ash to the cooling water. The ash flow rate passing through the heat transfer bed was from 0.4 to 2.2 kg/s. The ash average temperature was from 500 to 750 °C. And the heat transfer rate between the ash and the cooling water was between 150 and 300 W/(m2·°C). The relationships among the circulating ash temperature, the heat transfer, heat transfer rate, the heat transfer coefficient and the circulating ash flow passing through the heating exchange cell were also presented and could be used for further commercial EHE design.
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Sanford, MM. "Rewarming cardiac surgical patients: warm water vs warm air." American Journal of Critical Care 6, no. 1 (1997): 39–45. http://dx.doi.org/10.4037/ajcc1997.6.1.39.
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BACKGROUND: Hypothermia is experienced by 60% to 90% of adult patients after surgery. The detrimental physiological consequences of prolonged hypothermia are a significant risk for cardiac surgical patients. OBJECTIVE: To compare the effect of a warmed convective-air blanket with that of a warmed circulating-water blanket on the rates of increase in skin and core temperatures and on total rewarming time in patients with hypothermia after cardiac surgery. METHODS: A quasi-experimental, repeated-measures design was used to study rewarming in 76 adult patients who were hypothermic after cardiac surgery. Subjects were randomized to two groups: 40 were warmed with a convective-air blanket; 36, with a circulating-water blanket. Skin and core temperatures were recorded every 15 minutes until the subject's pulmonary artery temperature reached 37 degrees C. Total time required for rewarming was the period between time of placement of the blanket and time of removal. The effects of 13 other variables on the time required for rewarming were also determined. RESULTS: Both skin and core temperatures increased more rapidly in patients treated with the warm circulating-water blanket than in those treated with the convective-air blanket. The mean time required for rewarming was 45 minutes shorter in the group treated with the circulating-water blanket. The patient's age, volume of i.v. fluids received, length of anesthesia, starting core temperature, and treatment method had significant effects on the time required for rewarming. CONCLUSIONS: The data suggest that rewarming with a circulating-water blanket produces normothermia more rapidly than rewarming with a warm convective-air blanket in adult patients who are hypothermic after cardiac surgery.
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Mbawala, Shanel, Wambura Mwita, and Alexander Mtawa. "Stabilisation of Incubation Temperature in Hot Water Chicken Egg Incubator." Mbeya University of Science and Technology Journal of Research and Development 5, no. 4 (2024): 1–14. https://doi.org/10.62277/mjrd2024v5i40069.
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In this study, the existing egg incubator at Songwe Geothermal Hot Spring was improved by stabilising incubator temperature, hence improving hatching efficiency. The improved hot water egg incubator with a capacity of 280 eggs was designed, fabricated, and tested. Incubator temperature was stabilised by a variable flow rate of circulating hot water that corresponds to changes in incubator temperature. The flow rate of circulating hot water (1.5–2 litres/min) was proportional to the temperature of the incubator. A heat balance equation was formulated to quantify the heat transferred from hot water to circulating water, incubator circulating air, eggs, and the heat lost surrounding. Results revealed that the improved hot water egg incubator had an average hatching efficiency of 89% and a relatively stable temperature with a mean and standard deviation of 37.83°C and 0.1°C, respectively. The results showed a significant improvement as compared to the existing incubator, which had the capacity of 240 eggs, an average hatching efficiency of 84%, and relatively temperature stability with a mean and standard deviation of 37.3°C and 0.69°C, respectively. Results for the heat balance equation showed that most of the heat transferred from circulating water to the incubator was used to raise and maintain the temperature of the incubator at 37.8°C. The eggs absorbed a relatively small amount of heat, which was 3.136W. The improved incubator can also be operated by heat from geothermal resources and waste heat from industries and power plants in the 50°C 100°C temperature range.
Dissertations / Theses on the topic "Circulating water temperature"
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Joseph, Jyothis. "Improving Photovoltaic Panel Efficiency by Cooling Water Circulation." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1404617/.
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This thesis aims to increase photovoltaic (PV) panel power efficiency by employing a cooling system based on water circulation, which represents an improved version of water flow based active cooling systems. Theoretical calculations involved finding the heat produced by the PV panel and the circulation water flow required to remove this heat. A data logger and a cooling system for a test panel of 20W was designed and employed to study the relationship between the PV panel surface temperature and its output power. This logging and cooling system includes an Arduino microcontroller extended with a data logging shield, temperature sensing probes, current sensors, and a DC water pump. Real-time measurements were logged every minute for one or two day periods under various irradiance and air temperature conditions. For these experiments, a load resistance was chosen to operate the test panel at its maximum power point. Results indicate that the cooling system can yield an improvement of 10% in power production. Based on the observations from the test panel experiments, a cooling system was devised for a PV panel array of 640 W equipped with a commercial charge controller. The test data logger was repurposed for this larger system. An identical PV array was left uncooled and monitored simultaneously to compare the effect of cooling, demonstrating that the cooled array provided up to an extra 132W or 20% of maximum power for sunny weather conditions. Future expansion possibilities of the project include automated water level monitoring system and water filtration systems.
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Бейнер, Петр Сергеевич. "Информационно-измерительная система мониторинга температурного режима гидротехнических сооружений АЭС". Thesis, Национальный аэрокосмический университет им. Н. Е. Жуковского "Харьковский авиационный институт", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/24781.
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Диссертация на соискание ученой степени кандидата технических наук по специальности 05.13.05 – Компьютерные системы и компоненты. – Национальный технический университет "Харьковский политехнический институт", Харьков 2016. Диссертация посвящена разработке информационно-измерительной системы (ИИС) мониторинга гидротермических параметров АЭС для решения научно-практической задачи оптимизации функционирования энергосистемы путем компьютерной обработки данных о состоянии ГТС с учетом метеорологических факторов и объективного прогноза температурного режима циркуляционной воды. Разработана ИИС гидрометеорологических параметров АЭС с усовершенствованной системой измерения, передачи, сбора, архивирования и анализа параметров, влияющих на температурный режим циркуляционной воды в ГТС АЭС. Предложенная структура для распределенной ИИС, которая разработана в соответствии с техническим регламентом безопасной эксплуатации энергоблоков АЭС, позволяет проводить качественный мониторинг гидротермических процессов в системе оборотного водоснабжения АЭС, что допускает использование полученной информации для принятия обоснованных, взвешенных решений при корректировках суточного диспетчерского графика нагрузок АЭС во время сезонных ограничений. Разработаны принципы формирования единой базы данных метеорологической и гидротермической информации в ГТС, которая позволяет не только выполнять системную обработку данных, но и использовать информацию для достоверного прогнозирования гидротермического режима циркуляционной воды, участвующей в системе оборотного водоснабжения АЭС. Впервые предложена методика создания энергоэффективной структуры беспроводной сенсорной сети (БСС), позволяющей дистанционно измерять физические величины, распределенные на больших расстояниях. Использование предложенной БСС обусловлено следующими преимуществами для водных объектов АЭС, участвующих в системе охлаждения воды: отсутствием необходимости в прокладке кабелей для электропитания и передачи данных; низкой стоимость монтажа, пуска-наладки и технического обслуживания системы; минимальными ограничениями по размещению беспроводных устройств; возможностью внедрения и модификации сети на эксплуатируемом объекте без вмешательства в процесс функционирования; надежность и отказоустойчивость всей системы в целом при нарушении отдельных соединений между узлами. Получил развитие метод передачи гидрометеорологических параметров в ИИС на АЭС путем использования вероятностного шифрования информации в каналах связи, что позволило повысить степень защиты измерительной информации от несанкционированного доступа, а также увеличить помехоустойчивость. Применение вероятностной формы представления информации, позволяет воспользоваться следующими преимуществами: малый аппаратный объем; возможность функционирования в масштабе реального времени; повышенная помехозащищенность; существенно увеличена сложность проведения атак на основе статистических закономерностей функций шифрования; возможность внести дополнительный параметр безопасности, управляя законом распределения случайных чисел, для формирования вероятностного отображения, позволяет увеличить время жизни ключа. Разработаны программно-аппаратные средства для ИИС гидротермических параметров ГТС АЭС в режиме реального времени на основе Web-технологий. Программный комплекс позволяет сократить сроки получения, обработки и анализа гидрометеорологических данных, повысить достоверность и качество получаемых результатов, а также обеспечить сохранность информации. Разработанная программа прошла регистрацию в Государственном департаменте интеллектуальной собственности Украины.<br>Thesis for scientific degree candidate of technical sciences in the specialty 05.13.05 – computer systems and components. – National Technical University "Kharkov Polytechnic Institute", Kharkov 2016.
Dissertation is devoted to solving scientific and applied problems that concern the optimization of the NPP power system functioning. It is achieved by increasing monitoring accuracy of hydrothermal parameters at the hydrotechnical facilities taking into account hydrometeorological factors and the objective prediction of the circulating water temperature by means of the developed information-measurement system. The information-measurement system of the NPP hydrometeorological parameters was developed, with enhanced system of measurement, transfer, collection, backup, and analysis of parameters affecting the circulating water temperature at the NPP hydrotechnical facilities. Techniques to create energy-efficient structure of the wireless sensor networks were suggested, providing the remote measurement of the physical values extended over a large area of the NPP. The method of transferring hydrometeorological parameters within the information-measurement system was furthered, the probabilistic data encryption being used in the communication channels. It resulted in raising the security level of the measurement data against the unauthorized access and increasing the interference immunity.
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Stickley, Catherine Emma. "The palaeoceanographical significance of diatoms in Late Quaternary sediments from the south-west Pacific." Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314373.
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Бейнер, Петро Сергійович. "Інформаційно-вимірювальна система моніторингу температурного режиму гідротехнічних споруд АЕС". Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/24773.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.13.05 – Комп'ютерні системи та компоненти. – Національний технічний університет "Харківський політехнічний інститут", Харків 2016.
Дисертаційна робота присвячена розробці інформаційно-вимірювальної системи (ІВС) моніторингу гідротермічних параметрів АЕС для вирішення науково-практичної задачі оптимізації функціонування енергосистеми шляхом комп’ютерної обробки даних про стан гідротехнічних споруд (ГТС) з урахуванням метеорологічних факторів і об'єктивного прогнозу температурного режиму циркуляційної води. Розроблено ІВС гідрометеорологічних параметрів АЕС з удосконаленою системою вимірювання, передачі, збору, архівування і аналізу параметрів, що впливають на температурний режим циркуляційної води в ГТС АЕС. Запропоновано методику створення енергоефективної структури бездротової сенсорної мережі, що дозволяє дистанційно вимірювати фізичних величин, розподілені на великих відстанях на АЕС. Отримав розвиток метод передачі гідрометеорологічних параметрів в ІВС на АЕС шляхом використання імовірнісного шифрування інформації в каналах зв'язку, що дозволило підвищити ступінь захисту вимірювальної інформації від несанкціонованого доступу, а також збільшити завадостійкість.<br>Thesis for scientific degree candidate of technical sciences in the specialty 05.13.05 – computer systems and components. – National Technical University "Kharkov Polytechnic Institute", Kharkov 2016.
Dissertation is devoted to solving scientific and applied problems that concern the optimization of the NPP power system functioning. It is achieved by increasing monitoring accuracy of hydrothermal parameters at the hydrotechnical facilities taking into account hydrometeorological factors and the objective prediction of the circulating water temperature by means of the developed information-measurement system. The information-measurement system of the NPP hydrometeorological parameters was developed, with enhanced system of measurement, transfer, collection, backup, and analysis of parameters affecting the circulating water temperature at the NPP hydrotechnical facilities. Techniques to create energy-efficient structure of the wireless sensor networks were suggested, providing the remote measurement of the physical values extended over a large area of the NPP. The method of transferring hydrometeorological parameters within the information-measurement system was furthered, the probabilistic data encryption being used in the communication channels. It resulted in raising the security level of the measurement data against the unauthorized access and increasing the interference immunity.
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Sklut, Micah. "Investigating SST influence on the North Atlantic Oscillation using the NCAR community atmospheric model." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 5.62Mb, 121 p, 2005. http://wwwlib.umi.com/dissertations/fullcit/1428196.
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Chen, Chia-Jeng. "Hydro-climatic forecasting using sea surface temperatures." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/48974.
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A key determinant of atmospheric circulation patterns and regional climatic conditions is sea surface temperature (SST). This has been the motivation for the development of various teleconnection methods aiming to forecast hydro-climatic variables. Among such methods are linear projections based on teleconnection gross indices (such as the ENSO, IOD, and NAO) or leading empirical orthogonal functions (EOFs). However, these methods deteriorate drastically if the predefined indices or EOFs cannot account for climatic variability in the region of interest. This study introduces a new hydro-climatic forecasting method that identifies SST predictors in the form of dipole structures. An SST dipole that mimics major teleconnection patterns is defined as a function of average SST anomalies over two oceanic areas of appropriate sizes and geographic locations. The screening process of SST-dipole predictors is based on an optimization algorithm that sifts through all possible dipole configurations (with progressively refined data resolutions) and identifies dipoles with the strongest teleconnection to the external hydro-climatic series. The strength of the teleconnection is measured by the Gerrity Skill Score. The significant dipoles are cross-validated and used to generate ensemble hydro-climatic forecasts. The dipole teleconnection method is applied to the forecasting of seasonal precipitation over the southeastern US and East Africa, and the forecasting of streamflow-related variables in the Yangtze and Congo Rivers. These studies show that the new method is indeed able to identify dipoles related to well-known patterns (e.g., ENSO and IOD) as well as to quantify more prominent predictor-predictand relationships at different lead times. Furthermore, the dipole method compares favorably with existing statistical forecasting schemes. An operational forecasting framework to support better water resources management through coupling with detailed hydrologic and water resources models is also demonstrated.
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Choo, Hui C. "Peripheral blood flow changes in response to post-exercise cold water immersion." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2014. https://ro.ecu.edu.au/theses/1012.
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A reduction in body temperature is considered to be the primary mechanism by which cold water immersion (CWI) enhances short-term (h) recovery and improves exercise capacity in the heat. However, improvement in exercise performance may be optimised at a given cooling magnitude. Water temperature and immersion duration influence the magnitude of cooling in the core body, muscle and skin. Given the role of blood flow in convective heat flux, substrate delivery and metabolic waste clearance, it is important to understand the influence of different water temperatures on compartmental distribution of limb blood flow during CWI. Therefore, the purpose of this study was to compare blood flow changes in the common femoral artery, vastus lateralis muscle, and thigh skin induced by 5 min of post-exercise water immersion at 8°C, 14°C, 35°C or passive rest. In a randomised manner, nine recreationally active men performed exhaustive cycling in a climate control chamber (32.8 ± 0.4°C and 32 ± 5%rh), followed by 5 min of water immersion at 8.6 ± 0.2°C (WI8), 14.6 ± 0.3°C (WI14), 35.0 ± 0.4°C (WI35) or passive rest (CON). The exercise task involved 25 min of cycling at a power output equivalent to first ventilatory threshold, followed by high-intensity intermittent cycling (30 s at 90% of peak power output to 30 s at 70 W). Measurement of blood flow in thigh skin (laser Doppler flowmetry), vastus lateralis muscle (near infrared spectroscopy), and common femoral artery (Doppler ultrasound), heart rate, mean arterial pressure, skin, muscle, rectal, and mean body temperatures were obtained prior to exercise and up to 60 min post-immersion.
Both WI14 and WI8 reduced mean body, calf and thigh skin, and muscle temperatures, compared with WI35 and CON (p0.05). Relative to pre-immersion, differences were observed in the magnitude of reduction between skin, muscle, and common femoral blood flow. Decreases in muscle and skin blood flow were similar (p>0.05), but to a lesser extent when compared with femoral blood flow (p
Therefore, 5 min of CWI at 8°C and 14°C effectively reduced temperatures, when compared with CON and WI35. Although WI8 was more effective than WI14 in reducing mean body temperature, there was no influence on the decreases in skin, muscle and femoral blood flow. Furthermore, WI8 did not result in significant reduction in muscle blood flow compared to WI35, despite significant muscle cooling. Given that mean arterial blood pressure was elevated, it is possible hydrostatic effects during WI35, coupled with shivering thermogenesis during WI8 confounded extent of muscle blood flow reduction in the present study. As such, influence of hydrostatic pressure per se on peripheral blood flow cannot be ruled out although blood flow changes were similar between WI35 and CON. Additionally, current findings indicate unknown vascular beds, other than measured sites in the vastus lateralis muscle and thigh skin, contribute to overall changes in the limb blood flow. It appears that vasoconstriction in skin and muscle vasculatures are associated with the interaction between suppressed vasodilatory substances (e.g. nitric oxide) and altered baroreflex mediated sympathetic nerve activity. However, underlying mechanisms warrant further investigation.
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Lewis, Kayla Christine. "Numerical Modeling of Two-Phase Flow in the Sodium Chloride-Water System with Applications to Seafloor Hydrothermal Systems." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19810.
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In order to explain the observed time-dependent salinity variations in seafloor hydrothermal vent fluids, quasi-numerical and fully numerical fluid flow models of the NaCl-H2O system are constructed. For the quasi-numerical model, a simplified treatment of phase separation of seawater near an igneous dike is employed to obtain rough estimates of the thickness and duration of the two-phase zone, the amount of brine formed, and its distribution in the subsurface. For the fully numerical model, the equations governing fluid flow, the thermodynamic relations between various quantities employed, and the coupling of these elements together in a time marching scheme is discussed. The fully numerical model is benchmarked against previously published heat pipe and Elder problem simulation results, and is shown to be largely in agreement with those results. A number of simulation results are presented in the context of two-phase flow and phase separation within the framework of the single pass model. It is found that a quasi-stable two-phase (liquid + vapor) zone at depth below the hydrothermal discharge outlet gives rise to vent fluid with lower than normal seawater salinity. Additionally, it is shown that increasing the spatial extent of the two-phase zone can lower vent fluid salinity. The numerical approach used in this thesis is able to generate salinity patterns predicted by a widely held conceptual model of vent fluid salinity variation, and may be able to explain the vent fluid salinities and temperatures found at the Main Endeavour Vent Field on the Juan de Fuca Ridge, as this approach is able to produce simulated vent fluid salinities that match observed values from the Endeavour Field vents Dante and Hulk.
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Max, Lars [Verfasser], Ralf [Akademischer Betreuer] Tiedemann, and Dirk [Akademischer Betreuer] Nürnberg. "Millennial-scale changes in sea surface temperatures and intermediate water circulation in the northwest Pacific during the past 20,000 years / Lars Max. Gutachter: Ralf Tiedemann ; Dirk Nürnberg. Betreuer: Ralf Tiedemann." Bremen : Staats- und Universitätsbibliothek Bremen, 2012. http://d-nb.info/1072045915/34.
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Helánová, Blanka. "Energetická náročnost přípravy teplé vody." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226006.
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Master’s thesis on Energy performance of domestic hot water preparation is concerned with calculating and comparing the energy performance of domestic hot water preparation in two-generation family house with an administrative part. Energy performance of domestic hot water preparation is calculated by two calculation methods and by experimental measurements, which are compared at the end of the thesis. The calculation is performed according to standard ČSN 06 0320 and set of standards ČSN EN 15316-3. Thesis is processed in accordance with valid legislative regulations.
Books on the topic "Circulating water temperature"
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Gottlieb, Erik S. Currents, temperatures, and divergences observed in eastern central Lake Michigan during May-October 1984. U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Environmental Research Laboratories, 1989.
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F, James William, Barko John W, Tennessee Valley Authority, and United States. Army. Corps of Engineers., eds. Convective circulation during differential heating and cooling in the Minky Creek embayment of Guntersville Reservoir, data summary for 1991: Joint Agency Guntersville Project aquatic plant management. The Authority, 1993.
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Gottlieb, Erik S. Currents and temperatures observed in Lake Michigan from June 1982 to July 1983. U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Environmental Research Laboratories, 1989.
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Gottlieb, Erik S. Currents and water temperatures observed in Green Bay, Lake Michigan. U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Environmental Research Laboratories, 1990.
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Sullivan, Annett B. Modeling hydrodynamics, temperature, and water quality in Henry Hagg Lake, Oregon, 2000-03. U.S. Geological Survey, 2005.
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Sullivan, Annett B. Modeling hydrodynamics, temperature, and water quality in Henry Hagg Lake, Oregon, 2000-03. U.S. Geological Survey, 2005.
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Great Lakes Environmental Research Laboratory., ed. Nearshore current and temperature measurements, western Lake Michigan. U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Environmental Research Laboratories, Great Lakes Environmental Research Laboratory, 1997.
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Great Lakes Environmental Research Laboratory., ed. Nearshore current and temperature measurements, western Lake Michigan. U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Environmental Research Laboratories, Great Lakes Environmental Research Laboratory, 1997.
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Astrakhant͡sev, G. P. Modelirovanie techeniĭ i termicheskogo rezhima Ladozhskogo ozera. Akademii͡a nauk SSSR, In-t ozerovedenii͡a, 1988.
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C, Fleurant, and Atlantic Oceanographic and Meteorological Laboratories, eds. CTD/Ob2s, LADCP and XBT measurements collected aboard the R/V Seward Johnson, November-December 1998: North Brazil Current rings experiment cruise (NBC-1). U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Oceanic and Atmospheric Research Laboratories, Atlantic Oceanographic and Meteorological Laboratory, 1999.
Find full textBook chapters on the topic "Circulating water temperature"
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Deng, Hua Ling, Yong Wang, and Hong Zhao. "Unequal Interval Grey Forecast of the Rate of High Temperature Abrasion of Water-Wall Tubes in Circulating Fluidized Bed Boilers." In Key Engineering Materials. Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-456-1.805.
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Weisberg, Robert. "The Air–Sea Interactions that Determine Water Temperature." In Climate to a Fish Sandwich: Why We Study the Ocean’s Circulation. Springer Nature Switzerland, 2025. https://doi.org/10.1007/978-3-031-77592-5_10.
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Jiao, Kexin, Jianliang Zhang, Haibin Zuo, Runsheng Xu, and Jun Hong. "Calculation and Analysis the Influence on the Cooling Water Velocity and Hot Metal Circulation to the Long Life BF." In 5th International Symposium on High-Temperature Metallurgical Processing. John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118887998.ch73.
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Skinner, L. C., H. Elderfield, and M. Hall. "Phasing of millennial climate events and northeast Atlantic deep-water temperature change since 50 ka BP." In Ocean Circulation: Mechanisms and Impacts—Past and Future Changes of Meridional Overturning. American Geophysical Union, 2007. http://dx.doi.org/10.1029/173gm14.
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Nielsen-Gammon, John W., and Alison A. Tarter. "Climate Effects on Inflows." In Estuaries of the World. Springer Nature Switzerland, 2025. https://doi.org/10.1007/978-3-031-70882-4_3.
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AbstractClimate has a profound influence on the most fundamental properties of Texas bays and estuaries: their water temperatures and salinities, their circulation, and even their locations and spatial extents. With climate change, these influences will evolve and possibly change the character of bays and estuaries. Key climate changes include warmer temperatures, changes in amount and distribution of precipitation, and sea level rise. Inflows to Texas bays and estuaries are not altered solely by climate change, but it is possible to infer the impacts attributable to climate change. Specifically, hydrologic model simulations driven by downscaled climate model projections tend to predict roughly equal chances of increases or decreases in total inflows, but with a clear tendency for more erratic inflows as the wettest months get wetter and the driest months get drier. Projections of most hydrological variables have largely spread across models, indicating that change is likely, but the specific magnitude of change cannot be discerned at this time. Both increasing variability and a long-term trend imply that estuarine ecosystems must be able to adapt to a broader range of conditions than those found historically. Management decisions should allow for a range of possible future climate impacts.
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Stanev, E. V. "Assimilation of Sea Surface Temperature Data in a Numerical Ocean Circulation Model. A Study of the Water Mass Formation." In Data Assimilation. Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/978-3-642-78939-7_2.
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Yu, Xin, Yonghai Gao, Xinxin Zhao, and Shihao Li. "Research on Wellbore Temperature and Pressure Prediction of Oil-Based Drilling Fluid System in Deep Water Drilling Under the Condition of Coexistence of Overflow and Lost Circulation." In Mechanisms and Machine Science. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-68775-4_63.
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Jia, Changwu, Kuiyuan Ma, Wei Li, Gang Liu, Qingyuan Xue, and Zenghui Chen. "Research on Cold End Diagnosis and Optimization of Thermal Power Unit with Coal Consumption as Objective Function." In Advances in Transdisciplinary Engineering. IOS Press, 2022. http://dx.doi.org/10.3233/atde220489.
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In this paper, the optimal operation system of circulating water of thermal power unit is perfected. Through field test and theoretical calculation in different thermal power plants, the optimal operation mode of circulating water of different modes is determined under different load, water temperature and exhaust steam pressure of low-pressure cylinder. Taking the coal consumption rate of power supply unit as the objective function of circulating water system optimization, the analysis and calculation model of circulating water system optimization was established. The influence coefficient of exhaust steam pressure on power and heat consumption rate between low load condition and rated condition was studied by field measurement and theoretical calculation method, so as to improve the accuracy of optimization conclusion in low load condition.
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Falkenmark, Malin. "Approaching the Ultimate Constraint: Water Shortage in the Third World." In Resources and Population. Oxford University PressOxford, 1996. http://dx.doi.org/10.1093/oso/9780198289180.003.0007.
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Abstract This chapter addresses the relationships between natural resources and population from the perspective of water as fundamental to life. I start with the premise that a large number of the lowest-income countries suffer from water shortages. Since water-in spite of its renewable character--is a finite resource, I argue that population growth will exacerbate the problems of water deficiency. The presence of the water cycle constitutes a fundamental difference between Earth and other planets in the solar system. Life is made possible by the solar-driven circulation of water between three main spheres: the atmosphere, the lithosphere/ continents, and the oceans. The ecosystems are the results of complex biological interactions in the presence of solar energy, circulating water, and biogeochemical substances circulated by air and water. Because evaporative demand and therefore rainfall efficiency vary with air temperature, the same annual rainfall produces totally different ecosystems in different climatic zones. Rainfall seasonality also contributes to such differences.
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"MW steam turbine transformation technology using high-temperature circulating water for heating." In Resources, Environment and Engineering II. CRC Press, 2015. http://dx.doi.org/10.1201/b19136-70.
Full textConference papers on the topic "Circulating water temperature"
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Mori, S., T. Sato, and Y. Shimura. "Characterization of Amines under High Temperature Conditions and Their Use for Boiler Water Treatment." In CORROSION 2012. NACE International, 2012. https://doi.org/10.5006/c2012-01358.
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Abstract In the boiler water system, it is apparent that use of low volatility amine is effective to control pH of feed water and to maintain boiler water at higher pH even though makeup water is contaminated with organic substances which thermally decompose to organic acids. Various amines were characterized in the view of volatility, thermal stability and dissociation behavior at high temperature by using experimental boiler apparatus with maximum pressure up to 10.5 MPa and with maximum exhausting steam temperature up to 600 °C after attached superheater. One low volatility amine which is suitable for boiler water treatment was selected. The selected low volatility amine was applied to a boiler with superheater and a low-pressure special circulating boiler of which recovered steam condensate has been recently sometimes mixed with that of power generating boilers at the same site. It was confirmed that the amine showed good expected performance in the both boiler systems with the viewpoints of pH keeping ability at higher values and corrosion inhibition effect.
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Niedrach, Leonard W., and William H. Stoddard. "Corrosion Potentials and Corrosion Behavior of 304 Stainless Steel in High-Temperature Water Containing Both Dissolved Hydrogen and Oxygen." In CORROSION 1985. NACE International, 1985. https://doi.org/10.5006/c1985-85104.
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Abstract The corrosion potential of stainless steel in high-temperature water is affected markedly by the absolute and relative concentrations of dissolved hydrogen and oxygen as well as by mass transport of these species to the metal surface. This reflects the coupled electrochemical recombination reaction of the hydrogen and the oxygen on the surface. The fact that effects are more pronounced in water containing a stoichiometric excess of hydrogen than in the reverse case suggests that the electrochemical oxidation of hydrogen on an oxide covered steel electrode is markedly inhibited. The work also implies that monitoring and maintaining low oxygen concentrations in the circulating cooling water is more important than maintaining a specific hydrogen level as long as the latter is in considerable excess over the oxygen.
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Tachibana, Masahiko, Kazushige Ishida, Yoichi Wada, Ryosuke Shimizu, and Nobuyuki Ota. "Cathodic Polarization Properties of Hydrogen Peroxide and the Effect on Electrochemical Corrosion Potential Calculation under Simulated BWR Environment." In CORROSION 2013. NACE International, 2013. https://doi.org/10.5006/c2013-02155.
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Abstract Hydrogen peroxide (H2O2) is the most important oxidant to determine the corrosive environment of boiling water reactors (BWRs). Since H2O2 is unstable at high temperature and electrochemical measurement in high purity water is difficult, H2O2 polarization characteristics in the BWR environment are not known well especially at less than 10 ppb. Cathodic polarization curves of the H2O2 were measured in simulated BWR conditions at 553 K over range of 1 to 1000 ppb. A polytetrafluoroethylene chamber was set in a circulating autoclave to reduce decomposition of H2O2, and the potential step method developed for measurements under BWR conditions was employed. The exchange current density of the 2 ppb H2O2 condition was the same as the 100 ppb O2 condition though the O2 concentration was about fifty-fold higher than that of the H2O2. The results indicated that the H2O2 reduction reaction occurred faster than that of O2. The electrochemical corrosion potentials (ECPs) in the H2O2 environment were calculated using the obtained polarization curves. The ECPs increased from -0.55 Vvs.SHE to about 0 Vvs.SHE even at 10 ppb, and were in good agreement with the ECPs measured by electrometers. The obtained polarization curves of H2O2 are applicable to calculation of ECPs.
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Kiser, Samuel D., Evan B. Hinshaw, and Tino Orsini. "Extending the Life of Fossil Fired Boiler Tubing with Cladding of Nickel Based Alloy Materials." In CORROSION 2006. NACE International, 2006. https://doi.org/10.5006/c2006-06474.
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Abstract Fossil fuel fired boilers and circulating fluidized bed boiler tubing in the power industry are normally protected against corrosion using nickel based clad coatings. Weld overlay is the most common form of cladding that utilizes the pulsed gas metal arc welding process, however thermal spray processes using cored wires, powder, and solid wire nickel based consumables have been used as well. Good bond integrity, heat transfer, corrosion resistance, and cladding density are the essential cladding characteristics that provide optimum life of water wall tubes in the transition areas, air injection ports, super-heater and re-heater areas of a boiler. Increasingly, nickel base alloy cladding is not only used for repair and maintenance purposes, but is also used as a cost-effective and efficient alternative for new boiler installations. This paper describes field experience of nickel based materials of construction and repair, and reports laboratory results of a new, low NOx test method developed to screen various alloys and coatings for the power industry. Case history examples presented include the effective application of nickel alloy claddings for new boiler systems, as well as evaluations of materials that were previously exposed to high temperature and corrosive operating conditions. The inherent corrosion resistance, mechanical and physical properties of NiCr, NiCrMo, NiCrFe and NiCrFeAl qualify them as materials that meet or exceed high temperature corrosion and corrosion-erosion requirements.
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Yu Bai, Jiawei Xiao, Xiaochen Tang, Yongfu Liu, Houlin Liu, and Liang Dong. "Influence of water temperature variation on hydraulic performance of hot water circulating pump." In 2014 ISFMFE - 6th International Symposium on Fluid Machinery and Fluid Engineering. Institution of Engineering and Technology, 2014. http://dx.doi.org/10.1049/cp.2014.1146.
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Lu, Yesheng, Junning Cui, and Yue Zhao. "Ultra-precision temperature control of circulating cooling water based on fuzzy-PID algorithm." In 10th International Symposium on Precision Engineering Measurements and Instrumentation (ISPEMI 2018), edited by Jiubin Tan and Jie Lin. SPIE, 2019. http://dx.doi.org/10.1117/12.2512443.
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Deotto, Geoffrey, Olivier Brunin, Alexandre Nicoli, and Franck David. "Assessment of a Steam Generator Circulation Ratio by a Thermal Balance Based on External Wall Temperature Measurements." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-23153.
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During operation, sludge steadily appears at a slow pace on the secondary side of nuclear power plant steam generators. This leads to clogging of the tube bundle support plates, and consequently to a change in the thermal-hydraulic flow conditions. The circulation ratio of a steam generator is defined as the ratio between the total flowrate circulating in the riser and the steam flowrate at the outlet of the steam generator. This is a good indicator of the hydraulic pressure losses in the circulation loop. In particular, the increase in hydraulic resistance due to the tube support plate clogging leads to a drop in this parameter. For this reason, in order to check that clogging does not reach too high a level, the circulation ratio is regularly evaluated on steam generators of French nuclear power plants, and then compared to established safety limits. The purpose of this paper is to present an accurate method to determine the circulation ratio of a steam generator based on temperature measurements taken around the wall of the steam generator. This method consists of carrying out a thermal balance of the flow circulating in the downcomer. In order to accomplish this, the temperature of the water circulating in the downcomer is evaluated using thermocouple belts put on the external wall of the appliance. However, additional hypotheses in the calculation method are considered in order to take into account for the heat transfer between hot water inside the downcomer and the sensors. The steam generator circulation loop and the clogging of the tube support plates are presented in §1. Then §2 and §3 describe in detail the method and the associated hypotheses as well as the required instrumentation. Finally, §4 presents an application of this method to real cases of clogged steam generators.
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Jiang, Zhenxin, Zhenyu Tao, Zheng Wang, et al. "Equivalent Circulating Density Calculation After Gas Kick Considering Temperature and Pressure." In 58th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2024. http://dx.doi.org/10.56952/arma-2024-0179.
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ABSTRACT: Deep water is rich in oil and gas resources, which is of great significance to world energy. However, its reservoir geological conditions are complex, the drilling safety density window is narrow, the wellbore pressure is difficult to control, overflow, kick and other accidents are prone to occur, and there are high temperature and high pressure phenomena. In order to deal with a gas kick through managed pressure drilling in time after the gas kick, it is necessary to comprehensively consider the effects of temperature and pressure on the density and rheology of drilling fluid, and accurately calculate the bottom hole ECD after gas kick. Based on the wellbore multiphase flow model and considering the influence of temperature and pressure on the density and rheology of drilling fluid, combined with the special process flow of deep water managed pressure drilling, a more accurate ECD calculation method for deep water managed pressure drilling after gas kick is established in this paper. Verified by the data of well M in a sea area of China, the error of this method is 2% with high accuracy, which provides the basis for field managed pressure drilling. 1. INTRODUCTION With the development of oil and gas exploration and development technology in the world, the future exploration and development will gradually turn to deep unconventional oil and gas resources. Among them, the reserves of deep water oil and gas resources are rich, which may exceed 70 billion tons. Deepwater oil and gas resources are of great significance to world energy. However, its reservoir geological conditions are complex, the drilling safety density window is narrow, the wellbore pressure is difficult to control, overflow, kick and other accidents are prone to occur, and there are high temperature and high pressure phenomena. (Li, 2021; Li, et al, 2021; Yang, et al, 2023). Managed pressure drilling technology can accurately control the bottom hole pressure and quickly balance the bottom hole pressure difference, which is an important means to solve the drilling problem. (Yin, et al., 2020). ECD, the equivalent circulating density of drilling fluid, is a critical engineering parameter in the process of managed pressure drilling. If managed pressure is inaccurate, overflow and leakage will occur. Providing accurate ECD is the key to the successful implementation of managed pressure drilling. (Liu, et al, 2020; Fan, 2014).
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Hirasawa, Shigeki, and Tsuyoshi Kawanami. "Study on Collector Efficiency of Flat-Plate-Type Evacuated Solar Collector to Get Hot Water Near 100°C." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22242.
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We studied effects of parameters on collector efficiency of evacuated solar collector system to get hot water near 100°C. Change of temperature in the solar collector system is calculated for a daily change of solar radiation with 5 minutes cloud. Six operation-control methods are examined. Calculation results show that the effect of the control methods on average collector efficiency for one day is small as 1%. Best control method to minimize effect of the cloud on exit temperature fluctuation of the water is that the flow rate of the water is controlled proportional to the solar radiation. Two types of heat storage system are examined: a non-circulating type (supply new water and accumulate heated water in the heat storage tank) and a circulating type (circulating water from the heat storage tank). The non-circulating type is effective to use the solar energy in the daytime, and the circulating type is effective to use solar energy in the evening. Also, we measured temperature of a collector plate under actual solar radiation in a fine day.
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Li, Bodong, Guodong Zhan, Michael Okot, and Vahid Dokhani. "Analysis of Circulating Pressure and Temperature using Drilling Microchips." In International Petroleum Technology Conference. IPTC, 2023. http://dx.doi.org/10.2523/iptc-22805-ms.
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Abstract Accurate knowledge of circulating pressure and temperature is essential for making critical decisions while drilling operation. Through implementation of miniaturized semiconductor technology, we obtained near real-time dynamic pressure and temperature profile of the wellbore, making previously simulated critical operational data such as equivalent circulation density (ECD) and wellbore thermal distribution now measurable using drilling microchip. The application of drilling microchips to collect distributed pressure and temperature data while drilling is investigated, where each microchip measures both pressure and temperature simultaneously. This study also presents a revised method to calibrate measurements of drilling microchip with depth. Four field trials were attempted in a slightly inclined well using water-based or oil-based muds, where 10 drilling microchips were deployed in each trial. The recovered data from the drilling microchips are first downloaded and compiled. An in-house software is developed to process and convert time-scale of each drilling microchip to depth considering slippage of drilling microchips in drill string and annulus. An iterative algorithm is designed to calibrate the predicted arrival time with the actual arrival time of each tracer, which ultimately yields the true velocity of tracers in flow conduits. The maximum measured pressure is used as an indicator to locate each tracer at the bottom hole. It is realized that a plateau of pressure versus time can signify a trapped tracer in the flow path if the pump rate was maintained constant. The results of field trials show that some of the tracers were trapped for few minutes in the lower section of annular space or before the bit nozzle. The results of temperature profiles conclude a unique pattern for almost all of the deployed drilling microchips. However, the results of pressure profiles can be classified in two different groups as drilling microchips could have moved in different batches while pumping. The calculated temperature gradients show a heating zone near the bottom hole and continuous cooling of drilling fluid as tracers move toward the surface. The average pressure gradient is in the range of 0.52 – 0.61 psi/ft among different trials. It is shown that the velocity of tracers in each interval strongly depends on the flow regime. To our best knowledge, a combined measurement of circulating temperature and pressure using drilling microchips for the first-time is successfully conducted in these field trials. The results can be used for calculation of ECD and temperature profiles, which provide near real-time downhole data for monitoring and diagnostic applications. The measured pressure data also provide new insights about tracking of drilling microchips in the wellbore.
Reports on the topic "Circulating water temperature"
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Ramsey, Andree L., Heather H. Furey, and Amy S. Bower. Overturning of the Subpolar North Atlantic Program (OSNAP): RAFOS Float Data Report June 2014 - January 2019. Woods Hole Oceanographic Institution, 2022. http://dx.doi.org/10.1575/1912/29540.
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The Overturning in the Subpolar North Atlantic Program (OSNAP) is an international effort started in 2014 dedicated to achieving a better understanding of the link between dense-water formation and the meridional overturning circulation in the high-latitude North Atlantic. Moorings, gliders, and subsurface acoustically-tracked RAFOS floats have been used to collect temperature, salinity, and current data across the Labrador Sea, Irminger Sea, Reykjanes Ridge, Iceland Basin, Rockall-Hatton Plateau, and Rockall Trough. The specific objective of the OSNAP float program is to gather information on the pathways of the dense overflow waters transported by the deep limb of the overturning circulation and assess the connection of those pathways with currents observed crossing the OSNAP mooring line. This data report details the observations collected by 148 floats that were deployed for OSNAP during the summers of 2014, 2015, 2016 and 2017. Deployment locations were in the Iceland Basin, Irminger Sea, and in the Charlie-Gibbs Fracture Zone. Mission lengths ranged from 540-730 days, and the floats were ballasted to passively drift at a fixed pressure of either 1800, 2000, 2200, 2500, or 2800 dbar to tag the deep overflow water masses of the subpolar North Atlantic (Iceland-Scotland and Denmark Strait Overflow Waters).
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Frandsen, Martin, Jakob Vind Madsen, Rasmus Lund Jensen, and Michal Zbigniew Pomianowski. Domestic water measurement in two Danish office and educational buildings - Data set description. Aalborg University, 2022. http://dx.doi.org/10.54337/aau481810642.
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Measurement data of domestic water in non-residential buildings is sparse. More data is needed to describe the non-residential buildings’ domestic hot water (DHW) demand and to be able to design more efficient DHW systems. This DCE Technical Report aims to present and describe the data set: “Data set - Domestic water at CREATE and TMV23”. This data set contains measurement data from two office and educational buildings in Aalborg, Denmark. The measurements in the building CREATE are conducted from October 2018 to January 2019 and in the building TMV23 from April 2021 to May 2021. The data set consists of water flow rates and temperatures for the domestic cold water, domestic hot water, district heating for DHW production, and DHW circulation circuit.
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Bartolino, Valerio, Birgit Koehler, and Lena Bergström, eds. Climate effects on fish in Sweden : Species-Climate Information Sheets for 32 key taxa in marine and coastal waters. Department of Aquatic Resources, Swedish University of Agricultural Sciences, 2023. http://dx.doi.org/10.54612/a.4lmlt1tq5j.
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The purpose of this publication is to summarize the state of knowledge on the effects of environmental variability and climate change for individual species and stocks based on literature review, giving species-climate information for 32 key taxa in Swedish marine and coastal waters. The report is written in English. The extent and scale of recent changes in climate due to global warming is unprecedented and causes increasing effects on ecosystems. In oceans, ongoing warming leads to, for example, increased water temperatures, decreased ice cover and effects on hydrology and water circulation patterns that can in turn influence salinity. The environmental alterations affect species distribution, biology, and hence also the delivery of marine ecosystem services and human well-being. The results of this review on the effects of environmental variability and climate change on marine taxa are presented as species-climate information sheets designed in a user-friendly format aimed to enhance accessibility for professionals spanning different fields and roles, including e.g. scientific experts, NGOs affiliates and managers. The species-climate information sheets presented here cover 32 key taxa selected among the economically and ecologically most important coastal and marine fish and crustacean species in Swedish waters. The species-wise evaluations show that climate change leads to a wide range of effects on fish, reflecting variations in their biology and physiological tolerances. The review also highlights important data and knowledge gaps for each species and life stage. Despite the high variability and prevailing uncertainties, some general patterns appeared. On a general level, most fish species in Swedish marine and coastal waters are not expected to benefit from climate change, and many risks are identified to their potential for recruitment, growth and development. Boreal, marine and cold-adapted species would be disadvantaged at Swedish latitudes. However, fish of freshwater origin adapted to warmer temperature regimes could benefit to some extent in the Baltic Sea under a warming climate. Freshwater fish could also be benefitted under further decreasing salinity in the surface water in the Baltic Sea. The resulting effects on species will not only depend on the physiological responses, but also on how the feeding conditions for fish, prey availability, the quality of essential fish habitats and many other factors will develop. A wide range of ecological factors decisive for the development of fish communities are also affected by climate change but have not been explored here, where we focused on the direct effects of warming. The sensitivity and resilience of the fish species to climate change will also depend on their present and future health and biological status. Populations exposed to prolonged and intense fishing exploitation, or affected by environmental deterioration will most likely have a lower capacity to cope with climate change effects over time. For both the Baltic Sea and the North Sea, it is important to ensure continued work to update and improve the species-climate information sheets as results from new research become available. It can also be expected that new important and relevant biological information and improved climate scenarios will emerge continuously. Continued work is therefore important to update and refine the species-climate information sheets, help filling in currently identified knowledge gaps, and extend to other species not included here. Moreover, there is need to integrate this type of species-level information into analyses of the effects of climate change at the level of communities and ecosystems to support timely mitigation and adaptation responses to the challenges of the climate change.
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Rémy, Elisabeth, Romain Escudier, and Alexandre Mignot. Access impact of observations. EuroSea, 2023. http://dx.doi.org/10.3289/eurosea_d4.8.
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The accuracy of the Copernicus Marine Environment and Monitoring Service (CMEMS) ocean analysis and forecasts highly depend on the availability and quality of observations to be assimilated. In situ observations are complementary to satellite observations that are restricted to the ocean surface. Higher resolution model forecasts are required by users of the CMEMS global and regional ocean analysis and forecasts. To support this with an efficient observational constrain of the model forecast via data assimilation, an increase observation coverage is needed, associated with an improved usage of the available ocean observations. This work exploits the capabilities of operational systems to provide comprehensive information for the evolution of the GOOS. In this report, we analyse the use and the efficiency of the in-situ observations to constrain regional and global Mercator Ocean systems. Physical and biogeochemical variables are considered. The in-situ observations are used either to estimate physical ocean state at global and regional scale via data assimilation or to estimate BGC model parameters. The impact of the physical in situ observations assimilated in open ocean and coastal areas is assessed with numerical data assimilation experiments. The experiments are conducted with the regional 1/36° resolution and global 1/12° resolution systems operated by Mercator Ocean for the Copernicus Marine Service. For the global physical ocean, the focus is on the tropical ocean to better understand how the tropical mooring observations constrain the intraseasonal to daily variability and the complementarity with satellite observations and the deep ocean. The tropical moorings provide unique high frequency observations at different depth, but they are far away from each other, so part of the signal in the observation are decorrelated from one mooring to the others. It is only via an integrated approach, as data assimilation into a dynamical model and complementarity with other observing networks that those observations can efficiently constrain the different scales of variability of the tropical ocean circulation. As the satellite observations brings higher spatial resolution between the tropical moorings but for the ocean surface, we show that the tropical mooring and Argo profile data assimilation constrain the larger scale ocean thermohaline vertical structure (EuroSea D2.2; Gasparin et al., 2023). The representation of the high frequency signals observed at mooring location is also significantly improved in the model analysis compared to a non-assimilative simulation. The ocean below 2000 m depth is still largely under constrained as very few observations exist. Some deep ocean basins, as the Antarctic deep ocean, shows significant trend over the past decade but they are still not accurately monitored. Based on the spread of four deep ocean reanalysis estimates, large uncertainties were estimated in representing local heat and freshwater content in the deep ocean. Additionally, temperature and salinity field comparison with deep Argo observations demonstrates that reanalysis errors in the deep ocean are of the same size as or even stronger than the observed deep ocean signal. OSSE already suggested that the deployment of a global deep Argo array will significantly constrain the deep ocean in reanalysis to be closer to the observations (Gasparin et al., 2020). At regional and coastal scales, the physical ocean circulation is dominated by higher frequency, smaller scale processes than the open ocean which requires different observation strategy to be well monitor. The impact of assimilating high frequency and high-resolution observations provided by gliders on European shelves is analysed with the regional Iberic Biscay and Irish (IBI) system. It was found that repetitive glider sections can efficiently help to constrain the transport of water masses flowing across those sections. BGC ocean models are less mature than physical ocean models and some variable dependencies are still based on empirical functions. In this task, Argo BGC profile observations were used to optimize the parameters of the global CMEMS biogeochemical model, PISCES. A particle filter algorithm was chosen to optimize a 1D configuration of PISCES in the North Atlantic. The optimization of the PISCES 1D model significantly improves the model's ability to reproduce the North Atlantic bloom Recommendations on the in-situ network extensions for real time ocean monitoring are given based on those results, and the one also obtained in the WP2, Task 2.2 where data assimilation experiments but with simulated observations where conducted. Argo extension and the complementarity with satellite altimetry was also extensively studied. (EuroSea Deliverable ; D4.8)
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Circulating water subsystem design description: 4 x 350 MW(t) Modular HTGR [High-Temperature Gas-Cooled Reactor] Plant. Office of Scientific and Technical Information (OSTI), 1986. http://dx.doi.org/10.2172/464084.
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