scholarly journals Deformation and Surface Temperature Rise of 18-8 Austenitic Steels under Double-Repeated Fatigue Tests at Elevated Temperature

1968 ◽  
Vol 17 (182) ◽  
pp. 1009-1015
Author(s):  
Masao TANAKA ◽  
Kenji HATANAKA
Keyword(s):  
Elevated Temperature ◽  
Surface Temperature ◽  
Temperature Rise ◽  
Fatigue Tests ◽  
Austenitic Steels

Evaluation of Pitting Life of Carburized Gears Lubricated by ATF and Traction Oil

2000 ◽  
Author(s):  
Masashi Yamanaka ◽  
Kazuhiko Kishi ◽  
Katsumi Inoue ◽  
Masana Kato ◽  
Tomoya Masuyama ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Film Thickness ◽  
Surface Temperature ◽  
Fatigue Test ◽  
Temperature Rise ◽  
Fatigue Tests ◽  
Frictional Heat ◽  
Tooth Surface ◽  
Working Fluid ◽  
Traction Coefficient

Abstract This paper presents the result of fatigue tests carried out with an ATF and two types of traction oil. Since the performance of these oils as working fluid is preferred, the performance as a lubricant is inferior. The pitting life is evaluated by the value of D computed by the surface roughness and EHL film thickness. The high traction coefficient causes the tooth surface temperature rise by frictional heat, and then the oil film thickness and pitting life are decreased. To evaluate the performance of these oils as lubricants, the tooth surface temperature at the pitting tests is measured and the EHL film thickness is calculated with it for computing the value of D precisely. All results of fatigue test with three types of oils are examined together and it is found out that they are evaluated by the value of D only. The experimental formula to estimate the pitting life is obtained. This procedure is useful to design the surface gear strength of the automotive ATs and CVTs.

scholarly journals Characterization of Austenitic Stainless Steels with Regard to Environmentally Assisted Fatigue in Simulated Light Water Reactor Conditions

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 307
Author(s):  
Matthias Bruchhausen ◽  
Gintautas Dundulis ◽  
Alec McLennan ◽  
Sergio Arrieta ◽  
Tim Austin ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Fatigue Life ◽  
Elevated Temperature ◽  
Strain Rate ◽  
Power Plants ◽  
Research Effort ◽  
Hold Time ◽  
Strain Range ◽  
Austenitic Steels ◽  
Mean Strain

A substantial amount of research effort has been applied to the field of environmentally assisted fatigue (EAF) due to the requirement to account for the EAF behaviour of metals for existing and new build nuclear power plants. We present the results of the European project INcreasing Safety in NPPs by Covering Gaps in Environmental Fatigue Assessment (INCEFA-PLUS), during which the sensitivities of strain range, environment, surface roughness, mean strain and hold times, as well as their interactions on the fatigue life of austenitic steels has been characterized. The project included a test campaign, during which more than 250 fatigue tests were performed. The tests did not reveal a significant effect of mean strain or hold time on fatigue life. An empirical model describing the fatigue life as a function of strain rate, environment and surface roughness is developed. There is evidence for statistically significant interaction effects between surface roughness and the environment, as well as between surface roughness and strain range. However, their impact on fatigue life is so small that they are not practically relevant and can in most cases be neglected. Reducing the environmental impact on fatigue life by modifying the temperature or strain rate leads to an increase of the fatigue life in agreement with predictions based on NUREG/CR-6909. A limited sub-programme on the sensitivity of hold times at elevated temperature at zero force conditions and at elevated temperature did not show the beneficial effect on fatigue life found in another study.

scholarly journals Design of floating photovoltaic system for fish pond lighting

2021 ◽  
Vol 926 (1) ◽  
pp. 012005
Author(s):  
G S H Arimufti ◽  
W Sunanda ◽  
R F Gusa
Keyword(s):  
Surface Temperature ◽  
Water Temperature ◽  
Temperature Rise ◽  
Solar Irradiance ◽  
Output Voltage ◽  
Pond Water ◽  
Photovoltaic System ◽  
Fish Pond ◽  
Photovoltaic Panel

Abstract The floating photovoltaic panel is increasingly being used. This is one of the ways to reduce temperature rise in photovoltaic panel. The floating photovoltaic panel is used for lighting at the fish pond. A unit of 8-watt lamp for lighting supplied by 1 unit of 50 Wp photovoltaic panel and 1 unit of 12 V/3.5 Ah battery. The heatsink attached to the bottom of the floating photovoltaic panel transfers heat from the panel to the fish pond water. Sensors are connected to Arduino to measure photovoltaic panel output voltage and current, solar irradiance, photovoltaic panel temperature and fish pond water temperature. From the measurement, the voltage generated from the floating photovoltaic panel is 12.71 – 14.71 V and the current is 0.15 - 1.17 A. While the solar irradiance value is 71 W/m2 to 396 W/m2, the surface temperature of photovoltaic panel is 26.9°C - 32.4°C and fish pond water temperature is 27.1°C - 30.2°C.

scholarly journals Temperature Rise and Deformation Behaviors of Materials during Fatigue Tests at Cryogenic Temperatures

1987 ◽  
Vol 73 (1) ◽  
pp. 160-166 ◽  
Author(s):  
Toshio OGATA ◽  
Keisuke ISHIKAWA ◽  
Kotobu NAGAI ◽  
Tetsumi YURI
Keyword(s):  
Temperature Rise ◽  
Fatigue Tests ◽  
Cryogenic Temperatures ◽  
Deformation Behaviors

scholarly journals Estimates of climate system properties incorporating recent climate change

2018 ◽  
Vol 4 (1/2) ◽  
pp. 19-36 ◽  
Author(s):  
Alex G. Libardoni ◽  
Chris E. Forest ◽  
Andrei P. Sokolov ◽  
Erwan Monier
Keyword(s):  
Climate Change ◽  
Surface Temperature ◽  
21St Century ◽  
Climate Sensitivity ◽  
Temperature Rise ◽  
Heat Content ◽  
Climate System ◽  
Model Parameters ◽  
Aerosol Forcing ◽  
Global Mean

Abstract. Historical time series of surface temperature and ocean heat content changes are commonly used metrics to diagnose climate change and estimate properties of the climate system. We show that recent trends, namely the slowing of surface temperature rise at the beginning of the 21st century and the acceleration of heat stored in the deep ocean, have a substantial impact on these estimates. Using the Massachusetts Institute of Technology Earth System Model (MESM), we vary three model parameters that influence the behavior of the climate system: effective climate sensitivity (ECS), the effective ocean diffusivity of heat anomalies by all mixing processes (Kv), and the net anthropogenic aerosol forcing scaling factor. Each model run is compared to observed changes in decadal mean surface temperature anomalies and the trend in global mean ocean heat content change to derive a joint probability distribution function for the model parameters. Marginal distributions for individual parameters are found by integrating over the other two parameters. To investigate how the inclusion of recent temperature changes affects our estimates, we systematically include additional data by choosing periods that end in 1990, 2000, and 2010. We find that estimates of ECS increase in response to rising global surface temperatures when data beyond 1990 are included, but due to the slowdown of surface temperature rise in the early 21st century, estimates when using data up to 2000 are greater than when data up to 2010 are used. We also show that estimates of Kv increase in response to the acceleration of heat stored in the ocean as data beyond 1990 are included. Further, we highlight how including spatial patterns of surface temperature change modifies the estimates. We show that including latitudinal structure in the climate change signal impacts properties with spatial dependence, namely the aerosol forcing pattern, more than properties defined for the global mean, climate sensitivity, and ocean diffusivity.

Sign in / Sign up

Export Citation Format

Share Document