Heliostat drive unit design considerations – Site wind load effects on projected fatigue life and safety factor

Solar Energy ◽  
2014 ◽  
Vol 105 ◽  
pp. 170-180 ◽  
Author(s):  
James B. Blackmon
2015 ◽  
Author(s):  
Don W. Allen ◽  
Li Lee ◽  
Dean Henning ◽  
Stergios Liapis

Most deepwater tubulars experiencing high currents frequently require vortex-induced vibration (VIV) suppression to maintain an acceptable fatigue life. Helical strakes and fairings are the most popular VIV suppression devices in use today. Marine growth can significantly affect the VIV of a bare riser, often within just a few weeks or months after riser installation. Marine growth can have a strong influence on the performance of helical strakes and fairings on deepwater tubulars. This influence affects both suppression effectiveness as well as the drag forces on the helical strakes and fairings. Unfortunately, many VIV analyses and suppression designs fail to account for the effects of marine growth at all, even on a bare riser. This paper utilizes results from both high and low Reynolds number VIV test programs to provide some design considerations for managing marine growth for VIV suppression devices.


2013 ◽  
Vol 6 ◽  
pp. 145 ◽  
Author(s):  
Jan Gustincic ◽  
Lluís M. Garcia-Raffi
Keyword(s):  

2020 ◽  
Vol 980 ◽  
pp. 275-281
Author(s):  
Hu Jun

In order to consider the fluctuating wind load induced fatigue problem of long span suspension bridge, fatigue reliability formula is modified by assuming the fatigue life is accord with the weibull distribution. Based on the accurate bridge buffeting analysis of time history, the stress time history of components of a suspension bridge in east sea China is simulated, and then the fatigue damages and reliabilities are calculated. The results indicate that the main cables and hangers have enough fatigue reliability under the fluctuating wind load, the fatigue failure will not occur; the stiffening girder has larger fatigue damage, under 40 / (m.s-1) mean wind speed action, the girder of mid-support section’s average fatigue life is only 3.103 years, so the girder’s damage under strong wind action should be taken seriously.


2021 ◽  
pp. 754-777
Author(s):  
Hans Iwand ◽  
Joel Hassebrock

Abstract Because of the tough engineering environment of the railroad industry, fatigue is a primary mode of failure. The increased competitiveness in the industry has led to increased loads, reducing the safety factor with respect to fatigue life. Therefore, the existence of corrosion pitting and manufacturing defects has become more important. This article presents case histories that are intended as an overview of the unique types of failures encountered in the freight railroad industry. The discussion covers failures of axle journals, bearings, wheels, couplers, rails and rail welds, and track equipment.


2011 ◽  
Vol 354-355 ◽  
pp. 531-534
Author(s):  
Bin Zheng ◽  
Yong Qi Liu ◽  
Rui Xiang Liu ◽  
Jian Meng

In this paper, with the ANSYS, stress distribution, safety factor and fatigue life cycle of high-pressure common rail diesel engine connecting rod were analyzed by using 3D finite element method. The results show that the position of maximum principal stress is transition location of small end and connecting rod shank at maximum compression condition. The value of stress is 253.98 MPa in dangerous position. Safety factor is 2.67. The position of maximum principal stress is medial surface of small end at maximum stretch condition. The value of stress is 87.199 MPa in dangerous position. The fatigue life cycle of connecting rod is 2.6812×108. Fatigue safety factor is 1.5264.


2013 ◽  
Vol 405-408 ◽  
pp. 1022-1027
Author(s):  
Zi Fen Fang ◽  
Zhi Qiang Zhang ◽  
Fei Liu

The isolation of large-span Steel Truss Roof structure is developed on the basis of base isolation. The isolation of large-span Steel Truss Roof structure is to limit the transmission of wind load effect to the substructure. Based on the engineering background, we mainly discuss using rubber bearing isolation structure wind load effects. This paper will explains and demonstrates the isolation mechanism of Large-span Steel Truss Structure,and than test and verify isolation effect by Calculating through the analysis of wind tunnel tests conducted on the Yancheng financial services center, which the steel truss roof isolation bearings for wind load effect isolation effect.


Sign in / Sign up

Export Citation Format

Share Document