Research on Structural Strength of Catamaran Superstructure Constructed with Aluminum Alloy

2012 ◽  
Vol 538-541 ◽  
pp. 3165-3169
Author(s):  
Yuan Zhou Zheng ◽  
Yan Ling Huang ◽  
Kai Zhou Peng

The design of Superstructure constructed with aluminum alloy do not have to follow the traditional standard design method. It can be designed by applying strength theory and ANSYS program or MSC Patran / Nastran program, which can ensure the strength requirements with the selected aluminum alloy components and make the weight of the ship lightest. In this paper, the 42.4m catamaran sightseeing boat is used as an example. The structural strength of the superstructure constructed with aluminum alloy is calculated by MSC Patran / Nastran program. The distribution of the superstructure stress is obtained, which proved the size of the selected components of the superstructure can meet the requirements of the local strength and can be the reference of selecting the structure size. As the other conditions are unchanged, the the local thickness of the junction of the front wall and the side wall of the compass deck is changed. the relationship between plate thickness and stress is obtained. It is found that as The plate thickness is thicker, the stress there decreases; and as the thickness is smaller, it is obvious to reduce stress as the plate thickness Increase. when the thickness increases to a certain extent, the effect of the plate stress decreases is not obvious.

2020 ◽  
Vol 8 (8) ◽  
pp. 583
Author(s):  
Byeongkwon Jung ◽  
Jeong Hwan Kim ◽  
Jung Kwan Seo

Blast walls are installed on the topside of offshore structures to reduce the damage from fire and explosion accidents. The blast walls on production platforms such as floating production storage, offloading, and floating production units undergo fire and explosion risk analysis, but information about blast walls on the well-test area of drillship topsides is insufficient even though well tests are performed 30 to 45 times per year. Moreover, current industrial practices of design method are used as simplified elastically design approaches. Therefore, this study investigates the strength characteristic of blast wall on drillship based on the blast load profile from fire and explosion risk analysis results, as well as the ability of the current design scantling of the blast wall to endure the blast pressure during the well test. The maximum plastic strain of the FE results occurs at the bottom connection between the vertical girder and the blast wall plate. Based on the results, several alternative design applications are suggested to reduce the fabrication cost of a blast wall such as differences of stiffened plated structure and corrugated panels, possibility of changing material (mild steel), and reduced plate thickness for application in current industrial practices.


Author(s):  
Volodymyr Ivanov ◽  
Andrii Onyshchenko ◽  
Liudmyla Ivanova ◽  
Liudmyla Zasukha ◽  
Valerii Hryhorenko

The mobile house for two-phase litter rearing piglets was developed in the conditions of pasture their housing, the feature of which is that its side walls and roof are made in the form of two similar in shape and length of arched panels. In the back wall of the inner shield is a litter box, a self-feeder for piglets, a feed unit for a sow and a wicket, and in the front wall of the outer shield are doors with a wicket. Along with this, all walls and the roof of the litter box are made of transparent plastic, and the wall located near the self-feeding trough is also made perforated. In addition, the lower edge of the side wall of the inner arch-shaped shield has slides in which the lower edge of the side wall of the outer arc-shaped shield is inserted. A house with transformable fences has been developed to rear the young pigs. The structural feature of the house is the presence on the outside of the walls of the bobbins with a metal mesh edged at the bottom with a flexible sleeve. In order to ensure the conditions of gentle etching of the vegetation cover and to prevent damage to the turf of the pasture, the house can be completed with another type of hedge consisting of two hinged sections with doors on each side of the fence. In addition, the horizontal wings are rigidly attached to the hedge and connected by a metal mesh around the perimeter, the size of the cells of which ensures that the grass is eaten but prevents the turf of the pasture from being undermined. The developed devices for camp-pasture and feeding of maternal stock, suckling pigs, weaning pigs, repair and fattening pigs are well suited for year-round closed non-waste organic pork production using cultural and natural agricultural land. Key words: housing, feeding, devices, sows, piglets, young animals, pasture, organic pork.


2011 ◽  
Vol 346 ◽  
pp. 379-384
Author(s):  
Shu Bo Xu ◽  
Yang Xi ◽  
Cai Nian Jing ◽  
Ke Ke Sun

The use of finite element theory and modal analysis theory, the structure of the machine static and dynamic performance analysis and prediction using optimal design method for optimization, the new machine to improve job performance, improve processing accuracy, shorten the development cycle and enhance the competitiveness of products is very important. Selected for three-dimensional CAD modeling software-UG NX4.0 and finite element analysis software-ANSYS to set up the structure of the beam finite element model, and then post on the overall structure of the static and dynamic characteristic analysis, on the basis of optimized static and dynamic performance is more superior double wall structure of the beam. And by changing the wall thickness and the thickness of the inner wall, as well as the reinforcement plate thickness overall sensitivity analysis shows that changes in these three parameters on the dynamic characteristics of post impact. Application of topology optimization methods, determine the optimal structure of the beam ultimately.


Author(s):  
Werner Schiehlen ◽  
Makoto Iwamura

In this paper, we consider the problem to minimize the energy consumption for controlled multibody systems utilizing passive elastic elements for energy storage useful for robot systems in manufacturing. Firstly, based on the linearized equations of motion, we analyze the relationship between the consumed energy and the operating time, and the optimal trajectory using optimal control theory. Then, we verify the analytical solution by comparing with the numerical one computed considering the full nonlinear dynamics. After that we derive a condition for the operating time to be optimal, and propose the optimal design method for springs. Finally, we show the effectiveness of the design method by applying it to a 2DOF manipulator.


Author(s):  
Feilong Liu ◽  
Junhao Feng ◽  
Jia Xie ◽  
Quanke Feng ◽  
Martijn Van Den Broek ◽  
...  

Multi-column envelope engaging couples have been proposed for single screw compressors to reduce the friction and prolong the operational life. However, little is mentioned about the relationship between columns at opposite sides of the star-wheel teeth. An imbalance in the lubricant film forces would appear and influence the lubrication between the tooth and the groove. During a real design process, it is necessary to try several times for each different type of compressor to find the optimal combination of columns. In part, due to the large number of columns, it also makes both manufacturing processing and product testing difficult. In this paper, a synergy-column design method and its related manufacturing methods are presented. The locations and relationships of the designed columns can be prescribed by given the tooth width. Manufacturing of the rotor and star-wheel shows the new design method can be more efficient through processing. The stable operation results prove that the synergy-column envelope meshing pair can solve the star-wheel’s wear-out problem.


2017 ◽  
Vol 03 ◽  
pp. 42
Author(s):  
Bernard Ndirangu Wachira ◽  
Humphrey Opiyo Omondi ◽  
Josphat K. Kinyanjui ◽  
◽  
◽  
...  

The part played by non-prime household loans in improving the lives of many people who cannot afford collateral globally cannot be ignored. Many Microfinance Banks in many economies worldwide have tried to maintain the Grameen Bank Model of granting microloans, mainly non-prime household loans. However, the credit risks associated with this initiative hamper the pace at which the granting of this credit facility is expected to grow. This study intends to explore the relationship between the post loan disbursement allocation and the performance of non-prime household loans in the Microfinance Banks in Kenya. The theory associated to this study is the Credit Risk Theory. This theory, which is regarded as credit structural theory, was developed by Merton in 1972. The descriptive survey research design method was applied, and the sample size was 150 respondents. The data-collection tool used was a questionnaire. A logistic regression analysis was conducted for the purpose of predicting non-prime household performance in the Microfinance Banks using training budget, recoveries budget, percentage of training budget, and percentage of recoveries budget as predictors. The Wald test shows that training budget, recoveries budget, and percentage of training budget were good predictors, making a significant contribution to prediction. The percentage of budget on recoveries was not a significant predictor. The Microfinance Banks should enhance the performance of non-prime household loans through capacity building to the borrowers and educate the borrowers on dangers of enforced loan recoveries. The government, through the Central Bank of Kenya, should have a training policy for the Microfinance Banks so that they can enlighten the borrowers on proper financial management to avoid conflicts with borrowers during loan recoveries.


CERUCUK ◽  
2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Humaira Afrila ◽  
Markawie Markawie

Long Kali is a sub-district of Paser Tana Paser Regency Prov. East Kalimantan. In this sub-district have two village separate by a river, that is Perkuwen river, there is bridge has a broke. Whereas the village very needed a bridge because it is used as a transportation infrastructure for peoples and also passed by vehicles transporting oil palm yields . Therefore, the design of composite bridges made with spans 25 m and 7 m wide bridge.In this plan the analysis of Standard methods of loading refers to the bridge imposition For RSNI T-02-2005 about composite bridge structure design method, refers to RSNI T-03-2005 about Steel Structural Design For Bridge, SNI 03-1729-2002 about Steel Structures Planning Procedures and SNI 03-2847-2002 about Concrete Structures Calculation for Building.The result is used the main girder profile SH 950 x 400 x 16 x 32 and diaphragm WF 400 x 200 x 8 x 13. Vehicle floor plate thickness 20 cm using quality concrete  30 MPa and quality reinforcing steel reinforcement  360 MPa with subject dividers reinforcement D22- 100 and D12-100 mm. In using concrete pavement  30 MPa D22-100 mm staple reinforcement and shear reinforcement rebars quality D12-100 mm  360 MPa. Concrete abutment in the form  25 MPa at 2 m height and length of 8,5 m. Steel pipe pile foundations quality  25 MPa are 16 pieces with a length of 10 meters and a diameter of 0.4 m.Keyword: Bridge, composite, steel pipe pile.


Author(s):  
Srinivasa Rao Pedapati ◽  
Dhanis Paramaguru ◽  
Mokhtar Awang

As compared to normal Friction Stir Welding (FSW) joints, the Underwater Friction Stir Welding (UFSW) has been reported to be obtainable in consideration of enhancement in mechanical properties. A 5052-Aluminum Alloy welded joints using UFSW method with plate thickness of 6 mm were investigated, in turn to interpret the fundamental justification for enhancement in mechanical properties of material through UFSW. Differences in microstructural features and mechanical properties of the joints were examined and discussed in detail. The results indicate that underwater FSW has reported lower hardness value in the HAZ and higher hardness value in the intermediate of stir zone (SZ). The average hardness value of underwater FSW increases about 53% greater than its base material (BM), while 21% greater than the normal FSW. The maximum micro-hardness value was three times greater than its base material (BM), and the mechanical properties of underwater FSW joint is increased compared to the normal FSW joint. Besides, the evaluated void-area fraction division in the SZ of underwater FSW joint was reduced and about one-third of the base material (BM). The approximately estimated average size of the voids in SZ of underwater FSW also was reduced to as low as 0.00073 mm2, when compared to normal FSW and BM with approximately estimated average voids size of 0.0024 mm2 and 0.0039 mm2, simultaneously.


2021 ◽  
Vol 412 ◽  
pp. 11-26
Author(s):  
Marla Rodrigues Oliveira ◽  
Elizaldo Domingues Santos ◽  
Liércio André Isoldi ◽  
Luiz Alberto Oliveira Rocha ◽  
Mateus das Neves Gomes

This study is about a two-dimensional numerical analysis of the influence of a ramp in front on an oscillating water column wave energy converter (OWC-WEC). The main purpose was to evaluate, numerically and geometrically, the effect of using a ramp variation in relation to the frontal wall on the hydropneumatic power of the OWC-WEC. The constructal design method was applied for geometric analysis. The problem had a geometric constraint: the area of the ramp (A2) and two degrees of freedom: H2 / L2 (ratio of the height and length of the ramp) and L4 (the distance of the ramp concerning the OWC-WEC front wall). In numerical simulations, the equations of conservation of mass, momentum, and an equation for the transport of volumetric fraction were solved using the finite volume method (FVM). The multiphase model volume of fluid (VOF) was applied for the air-water interaction. Thus, the increase in the H2/L2 ratio resulted in a decrease of the root mean square (RMS) of the available hydropneumatic power (Phyd). By varying the distance L4, the better case was = 6 m and / = 0.025 and the worst case was = 1 m and / = 0.2. The relative difference between the better RMS Phyd = 150.7957 W and the worst Phyd = 73.1164 W reached up to a hundred and six percent.


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