Effects of Water Flow Rate on Fatigue Life of Carbon Steel in Simulated LWR Environment Under Low Strain Rate Conditions

2003 ◽  
Vol 125 (1) ◽  
pp. 52-58 ◽  
Author(s):  
Akihiko Hirano ◽  
Michiyoshi Yamamoto ◽  
Katsumi Sakaguchi ◽  
Tetsuo Shoji ◽  
Kunihiro Iida
Keyword(s):  
Fatigue Life ◽  
Carbon Steel ◽  
Strain Rate ◽  
Water Flow ◽  
Flow Rate ◽  
Water Flow Rate ◽  
Flow Rates ◽  
Life Evaluation ◽  
Significant Difference ◽  
Fatigue Life Evaluation

The flow rate of water flowing on a steel surface is considered to be one of the important factors strongly influencing the fatigue life of the steel, because the water flow produces difference in the local environmental conditions. The effect of the water flow rate on the fatigue life of a carbon steel was thus investigated experimentally. Fatigue testing of the carbon steel was performed at 289°C for various dissolved oxygen contents (DO) of less than 0.01 and 0.05, 0.2, and 1 ppm, and at various water flow rates. Three different strain rates of 0.4, 0.01, and 0.001 %/s were used in the fatigue tests. At the strain rate of 0.4 %/s, no significant difference in fatigue life was observed under the various flow rate conditions. On the other hand, at 0.01 %/s, the fatigue life increased with increasing water flow rate under all DO conditions, such that the fatigue life at a 7 m/s flow rate was about three times longer than that at a 0.3 m/s flow rate. This increase in fatigue life is attributed to increases in the crack initiation life and small-crack propagation life. The major mechanism producing these increases is considered to be the flushing effect on locally corrosive environments at the surface of the metal and in the cracks. At the strain rate of 0.001 %/s, the environmental effect seems to be diminished at flow rates higher than 0.1 m/s. This behavior does not seem to be explained by the flushing effect alone. Based on this experimental evidence, it was concluded that the existing fatigue data obtained for carbon steel under stagnant or relatively low flow rate conditions may provide a conservative basis for fatigue life evaluation. This approach seems useful for characterizing fatigue life evaluation by expressing increasing fatigue life in terms of increasing water flow rate.

Method to Evaluate Fatigue Life of Carbon Steel Under Simulated Synchronously Changing BWR Condition

2007 ◽  
Author(s):  
Akihiko Hirano ◽  
Kazunari Uchida ◽  
Katsumi Sakaguchi
Keyword(s):  
Fatigue Life ◽  
Carbon Steel ◽  
Dissolved Oxygen ◽  
Strain Rate ◽  
Oxygen Concentration ◽  
Water Flow ◽  
Flow Rate ◽  
Water Flow Rate ◽  
Fatigue Tests ◽  
Dissolved Oxygen Concentration

The environmental fatigue life of carbon steel is influenced by BWR conditions such as water temperature, dissolved oxygen concentration, water flow rate and so on. These parameters change inconstantly during operation of BWR plants and strain rate changes in the structural components due to the temperature change. In general, fatigue life evaluation equations have been formulated based on the fatigue data obtained under constant conditions. To apply these equations to evaluate the fatigue life of actual components, a study is necessary to confirm the applicability of the proposed equations to the changing conditions. In this study, fatigue tests were performed under changing conditions of strain amplitude, strain rate, temperature, dissolved oxygen concentration and water flow rate. It was confirmed that the proposed fatigue life equation could predict the fatigue life under changing conditions.

Modified Rate Approach Method to Evaluate Fatigue Life of Carbon Steel Under Simulated Synchronously Changing BWR Conditions

2006 ◽  
Author(s):  
Akihiko Hirano ◽  
Katsumi Sakaguchi
Keyword(s):  
Fatigue Life ◽  
Carbon Steel ◽  
Dissolved Oxygen ◽  
Strain Rate ◽  
Water Flow ◽  
Flow Rate ◽  
Water Flow Rate ◽  
Fatigue Tests ◽  
Temperature Changes ◽  
Approach Method

The fatigue life of carbon steel is influenced by Boiling Water Reactor (BWR) conditions such as water temperature, dissolved oxygen concentration, water flow rate and so on. These parameters changes constantly during the operation of BWR plants and strain rate changes in the structural components occur because of temperature changes. In general, fatigue life evaluation equations have been formulated based on fatigue data obtained under constant conditions. Before using these equations to evaluate the fatigue life of actual components, a study is necessary to make sure they are applicable to changing conditions. In this study, fatigue tests were performed under changing strain amplitude, strain rate, temperature, dissolved oxygen content, and water flow rate conditions. It was confirmed that the proposed fatigue life equation could predict the fatigue life under practical changing conditions.

K-2217 Effects of Water Flow Rate on Fatigue Life of Carbon Steel in Simulated BWR Environment

2001 ◽  
Vol V.01.1 (0) ◽  
pp. 291-292
Author(s):  
Akihiko HIRANO ◽  
Michiyoshi YAMAMOTO ◽  
Katsumi SAKAGUCHI ◽  
Tetsuo SHOJI ◽  
Kunihiro IIDA
Keyword(s):  
Fatigue Life ◽  
Carbon Steel ◽  
Water Flow ◽  
Flow Rate ◽  
Water Flow Rate

Effects of Water Flow Rate on Fatigue Life of Ferritic and Austenitic Steels in Simulated LWR Environment

2002 ◽  
Author(s):  
Akihiko Hirano ◽  
Michiyoshi Yamamoto ◽  
Katsumi Sakaguchi ◽  
Tetsuo Shoji ◽  
Kunihiro Iida
Keyword(s):  
Stainless Steel ◽  
Fatigue Life ◽  
Carbon Steel ◽  
Water Flow ◽  
Flow Rate ◽  
Fatigue Testing ◽  
Water Flow Rate ◽  
High Water ◽  
Low Sulfur ◽  
Fatigue Life Reduction

The flow rate of water flowing over a steel surface is considered to be one of the most important factors influencing the fatigue life of the steel, because the water flow produces differences in the local environment. The effect of the water flow rate on the fatigue life of carbon, low alloy, and austenitic stainless steels was therefore investigated experimentally. Fatigue testing of low (S = 0.008 wt%) and high (S = 0.016 wt%) sulfur content carbon steels and a low alloy steel was performed at 289°C for various dissolved oxygen concentrations (DO) of less than 0.01 and 0.05, 0.2, and 1 ppm, and at various water flow rates. Three different strain rates of 0.4, 0.01, and 0.001%/s were used in the fatigue tests. For high sulfur carbon steel (S = 0.016 wt%), the effect of a high water flow rate on mitigating fatigue life reduction was more clearly observed at a lower strain rate, irrespective of the DO. This effect of high water flow rate was most notable at a DO of 0.2 ppm, which was the DO level that produced a significant sulfur effect. This indicates that the mechanism responsible for the mitigation of fatigue life reduction is the flushing effect of the water, which eliminates the locally corrosive environment. For high sulfur carbon steel (S = 0.016 wt%), no benefit of a high water flow rate was found at a DO of 0.01 ppm. This was because the environmental effect is insignificant at this low DO level. For low sulfur carbon steel (S = 0.008 wt%) and low alloy steel (S = 0.008 wt%), a high water flow rate had little effect on mitigating fatigue life reduction even at a DO of 0.2 ppm. This indicates that the sulfur is much less influential in low sulfur steel than in high sulfur steel. Fatigue testing of Type 316 nuclear grade stainless steel (316NG) and Type 316 stainless steel (SUS316) was performed at 289°C and 320°C for DO levels of less than 0.01 and 0.05, and 0.2. For austenitic stainless steel, no mitigating effect at a high water flow rate was found. It should be noted rather that there is a possibility that a high water flow rate decreases the fatigue life because a tendency to a slight decrease in fatigue life with an increasing flow rate was observed.

201 Impact of Water Flow Rate on Finishing Pig Performance

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 68-69
Author(s):  
Hannah E Miller ◽  
Jorge Y Perez-Palencia ◽  
Crystal L Levesque ◽  
Robert C Thaler
Keyword(s):  
Body Weight ◽  
Water Flow ◽  
Flow Rate ◽  
Water Flow Rate ◽  
Low Flow ◽  
Flow Rates ◽  
Finishing Pig ◽  
Daily Water ◽  
Pig Performance ◽  
High Treatment

Abstract A survey of South Dakota pork producers in 2019 demonstrated that water flow rate for nipple drinkers was highly variable among barns. Sixty-eight percent had water flow rates above the recommended rate of 500–1,000 mL/min (NSNG, 2010). The objective of this study was to determine the impact of water flow rate on finishing pig performance during the summer months. A total of 396 mixed-sex pigs, in two groups, were utilized in a 77-day trial (34.55 to103.8 kg BW) with 6 pigs/pen. Pens were assigned to one of three water flow rates (high, medium, low) based on the 3-hole diameters of the commercial water nipples used in the facility (2.0, 1.0, 0.80 mm; n = 22 pens/treatment). Daily water usage was recorded for each treatment along with room temperature, outside temperature, and relative humidity. Individual pen water flow rate was recorded every two weeks. At every diet phase change (26± 2.6 days), feed disappearance and individual pig body weight were recorded. Water flow rates averaged 1846±188, 906±214, 508±100 mL/min for high, medium, and low flow rates, respectively. Daily water disappearance for high, medium, and low treatments were 6.8, 2.3, 1.7±3.2 liters/pig, respectively. Final body weight (BW; 103.8±7.4 kg) did not differ. Daily gain (ADG) from 34.5±4.5 to 55.5±4.6 kg BW was greatest (P < 0.05) for high treatment. Daily intake (ADFI) and gain:feed (G:F) from 55.5±4.6 to 79.1±5.3 kg BW were greatest (P < 0.05) for high treatment. Cumulative ADFI was 2.27, 2.18, 2.16±0.16 kg (P < 0.05) in high, medium, and low flow ranges, respectively. There was no differences in cumulative ADG or G:F. Water flow rate had a significant impact on ADFI although there was minimal impact on gain and G:F. Water nipples should be regularly checked as part of normal barn maintenance to ensure adequate, but not excessive, water is available.

Effects of Water Flow Rate on Fatigue Life of Structural Steels Under Simulated BWR Environment

2007 ◽  
Author(s):  
Akihiko Hirano ◽  
Katsumi Sakaguchi ◽  
Tetsuo Shoji
Keyword(s):  
Stainless Steel ◽  
Fatigue Life ◽  
Water Flow ◽  
Flow Rate ◽  
Environmental Effect ◽  
Water Flow Rate ◽  
High Flow ◽  
High Flow Rate ◽  
Sulfur Concentration ◽  
Type 304

Fatigue tests in simulated LWR environment of carbon and stainless steels were performed under high water flow rates between 7 to 10 m/s. For carbon steel, high flow rate of water clearly mitigated the environmental effect on the fatigue life at the high sulfur concentration of 0.016% which caused high environmental effect on a fatigue life. On the contrary, high flow rate of water slightly enhanced the environmental effect at the low sulfur concentration at or less than 0.008% which caused very low environmental effect. These results suggested that the environmental fatigue life under various flow rate conditions should be determined by the combination between the mitigating effect caused by flushing of the severe local environment and the enhancing effect caused by increase in corrosion potential. Low alloy steel showed the similar behavior as carbon steel. For stainless steel, flow rate had little effect on the fatigue life of type 316NG stainless steel. It suggested that there was no role of water flushing. For type 304 and 304L stainless steel, fatigue life has a tendency to decrease with increase in water flow rate. Fatigue lives of type 304 stainless steel under high flow rate of 7 to 10 m/s were shorter than those predicted by proposed fatigue life prediction equation by the Japanese EFT committee. This effect should be considered in an evaluation of environmental fatigue. No water flow effect was found in cast stainless steel.

scholarly journals Performance of Solar Absorption-Subcooled Compression Hybrid Cooling System for Different Flow Rates of Hot Water

2020 ◽  
Vol 10 (3) ◽  
pp. 810 ◽  
Author(s):  
Jinfang Zhang ◽  
Zeyu Li ◽  
Yue Jing ◽  
Yongrui Xu
Keyword(s):  
Energy Saving ◽  
Water Flow ◽  
Flow Rate ◽  
Cooling System ◽  
Water Flow Rate ◽  
Hot Water ◽  
Solar Absorption ◽  
Flow Rates ◽  
High Rise ◽  
Daily Energy

The solar absorption-subcooled compression hybrid cooling system (SASCHCS) is tech-economically feasible for high-rise buildings. Since such a system operates with no auxiliary heat source, the performance coupling of its absorption subsystem and solar collectors is sensitive to the variation of hot water flow rate. In this regard, the relationship of system performance and hot water flow rate is required to be clarified exactly. Therefore, this paper aims to illustrate the effect mechanism of hot water flow rate and to propose the corresponding decision criterion. The case study is based on a typical high-rise office building in subtropical Guangzhou. The daily working process of this system with different hot water flow rates is simulated and analyzed. Subsequently, the useful heat of collectors and cooling capacity of the absorption subsystem with the hot water flow rate is discussed in detail. The results show that the SASCHCS operates with hot water temperatures ranging from 60 °C to 90 °C. The energy saving increases with the rise of hot water flow rate, but such variation tends to be flat for the excessively high flow rate. As the collector flow rate increases from 1 m3/h to 10 m3/h, the daily energy saving improves by 21% in August. Similarly, the daily energy saving increases by 37.5% as generator hot water flow rate increases from 1 m3/h to 10 m3/h. In addition, the collector flow rate of 3.6 m3/h (13.33 (kg/m2 h)) and the generator flow rate of 5.2 m3/h (19.26 (kg/m2 h)) are optimal for the annual operation, with considering power consumption of water pumps. This paper is helpful for the improvement of SASCHCS operating performance.

scholarly journals Experimental Study on Thermal Radiation Attenuation Using Water Mist of Twin-fluid Atomizer

2021 ◽  
Vol 35 (4) ◽  
pp. 24-32
Author(s):  
Jae Geun Jo ◽  
Chi Young Lee
Keyword(s):  
Thermal Radiation ◽  
Water Flow ◽  
Flow Rate ◽  
Air Flow ◽  
Water Flow Rate ◽  
Water Mist ◽  
Air Flow Rate ◽  
Radiation Attenuation ◽  
Rate Condition ◽  
Flow Rates

In this study, the thermal radiation attenuation performance of water mist was investigated using twin-fluid atomizers. The water and air flow rates of Small atomizer were 36~105 g/min and 10~30 L/min, whereas those of Large atomizer were 37~300 g/min and 20~60 L/min, respectively. In the present experimental range, the thermal radiation attenuation of Small atomizer and Large atomizer were 6.1~11.9% and 5.2~14.6%, respectively. With the increase in water and air flow rates, the thermal radiation attenuation increased, and under similar water and air flow rate conditions, Small atomizer showed higher thermal radiation attenuation than Large atomizer. Based on the present experimental data, it was found that the air (gas) discharge area is a potentially important factor in determining the thermal radiation attenuation performance. Additionally, through the analysis of thermal radiation attenuation per unit water flow rate, it was confirmed that the twin-fluid atomizer can result in higher thermal radiation attenuation than the single-fluid atomizer under the same water flow rate condition.

scholarly journals Fatigue Life Evaluation Method of Carbon Steel in High Temperature Pure Water Environment.

1999 ◽  
Vol 65 (634) ◽  
pp. 1370-1376 ◽  
Author(s):  
Atsuya HIRANO ◽  
Akihiko HIRANO ◽  
Satoshi KANNO ◽  
Michiyoshi YAMAMOTO ◽  
Makoto HAYASHI
Keyword(s):  
High Temperature ◽  
Fatigue Life ◽  
Carbon Steel ◽  
Evaluation Method ◽  
Pure Water ◽  
Water Environment ◽  
Life Evaluation ◽  
Fatigue Life Evaluation

Displacement of Fluometuron and Diuron through Saturated Glass Beads and Soil

Weed Science ◽  
1968 ◽  
Vol 16 (4) ◽  
pp. 544-548 ◽  
Author(s):  
J. M. Davidson ◽  
P. W. Santelmann
Keyword(s):  
Water Flow ◽  
Flow Rate ◽  
Glass Bead ◽  
Water Flow Rate ◽  
Soil Surface ◽  
Chloride Ion ◽  
Glass Beads ◽  
Low Flow ◽  
Flow Rates ◽  
Loam Soil

Solutions containing 3-(m-trifluromethylphenyl)-l,l-di-methylurea (fluometuron) or 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron) were displaced through saturated 250-μ glass beads or through Norge loam soil at two water flow rates. The procedure used allowed uniform application of herbicide solutions to the soil surface and subsequent displacement of the herbicide through soil or glass bead columns at a constant water flow rate. Fluometuron was as mobile as the chloride ion at both high and low flow rates. The shape of the fluometuron distribution curves obtained at the two flow rates were distinctly different. The volume of water required to displace fluometuron through a material that adsorbed the herbicide was greater than that necessary to displace the fluometuron through materials giving a smaller amount of adsorption. More diuron was adsorbed by the glass bead system than fluometuron.

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