Innovative manufacture of impulse turbine blades for wave energy power conversion

Author(s):  
A Thakker ◽  
C Sheahan ◽  
P Frawley ◽  
H B Khaleeq

An innovative approach to the manufacture of impulse turbine blades using rapid prototyping, fused decomposition modelling (FDM), is presented in this paper. These blades were designed and manufactured by the Wave Energy Research Team (WERT) at the University of Limerick for the experimental analysis of a 0.6m impulse turbine with fixed guide vanes for wave energy power conversion. The computer aided design/manufacture (CAD/CAM) package Pro-Engineer 2000i was used for three-dimensional solid modelling of the individual blades. A detailed finite element analysis (FEA) of the blades under centrifugal loads was performed using Pro-Mechanica. Based on this analysis and FDM machine capabilities, blades were redesigned. Finally, Pro-E data were transferred to an FDM machine for the manufacture of turbine blades. The objective of this paper is to present the innovative method used to design, modify and manufacture blades in a time and cost effective manner using a concurrent engineering approach.

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Yu-Ling Wu ◽  
Ming-Hsu Tsai ◽  
Hung-Shyong Chen ◽  
Yu-Tsen Chang ◽  
Tsai-Te Lin ◽  
...  

Abstract The use of aftermarket computer-aided design/computer-assisted manufacturing (CAD/CAM) prosthesis components in dental implants has become popular. This study aimed to (1) compare the accuracy of aftermarket CAD/CAM screws with that of original equipment manufacturer (OEM) abutment screws and (2) examine the biomechanical effects of different abutment screws used with zirconia abutment in an implant fixture by using three-dimensional finite element analysis (FEA). Significantly different measurements were obtained for the aftermarket CAD/CAM and OEM screws. The FEA results indicated that under the same loading condition, the maximum stress of the aftermarket CAD/CAM screws was 15.9% higher than that of the OEM screws. Moreover, the maximum stress position occurred in a wide section of the OEM screws but in the narrowest section of the aftermarket screws. The stress of the OEM zirconia abutment was 14.9% higher when using the aftermarket screws than when using the OEM screws. The effect of the manufacturing differences between aftermarket and OEM screws on the clinical effect of aftermarket screws is unpredictable. Therefore, aftermarket screws should be cautiously used clinically.


2004 ◽  
Vol 126 (02) ◽  
pp. 26-29 ◽  
Author(s):  
Jean Thilmany

Iowa State researchers are working on technology to let engineers design and analyze in real time surrounded by three-dimensional virtual reality. The goal for virtual engineering is for the engineer to better focus on solving the problem at hand, without spending undue amounts of time gathering information, modelling the information, and then analyzing it. The virtual engineering system would integrate computational fluid dynamics and finite element analysis modelling and simulation technologies so engineers would feel as though they’re walking through a system, like a power plant, testing as they go. According to experts, the challenge of building a complete virtual engineering environment comes while coupling software packages as well as in the limitations of visualization and computing hardware prevalent currently. Howard Crabb, one of the founding fathers of computer-aided design technology, predicts that virtual engineering will become cost-effective within the decade. He’s the author of The Virtual Engineer, a book that defines how companies can use the powerful supercomputing capabilities available today to streamline business practices.


Author(s):  
Hossam S. Badawi ◽  
Sherif A. Mourad ◽  
Sayed M. Metwalli

Abstract For a Computer Aided Design of a concrete truck mixer, a six cubic meter concrete mixer drum is analyzed using the finite element method. The complex mixer drum structure is subjected to pressure loading resulting from the plain concrete inside the drum, in addition to its own weight. The effect of deceleration of the vehicle and the rotational motion of the drum on the reactions and stresses are also considered. Equivalent static loads are used to represent the dynamic loading effects. Three-dimensional shell elements are used to model the drum, and frame elements are used to represent a ring stiffener around the shell. Membrane forces and bending stresses are obtained for different loading conditions. Results are also compared with approximate analysis. The CAD procedure directly used the available drafting and the results were used effectively in the design of the concrete mixer drum.


2013 ◽  
Vol 2013 (HITEN) ◽  
pp. 000056-000060 ◽  
Author(s):  
Z. Cole ◽  
B. S. Passmore ◽  
B. Whitaker ◽  
A. Barkley ◽  
T. McNutt ◽  
...  

In high frequency power conversion applications, the dominant mechanism attributed to power loss is the turn-on and -off transition times. To this end, a full-bridge silicon carbide (SiC) multi-chip power module (MCPM) was designed to minimize parasitics in order to reduce over-voltage/current spikes as well as resistance in the power path. The MCPM was designed and packaged using high temperature (> 200 °C) materials and processes. Using these advanced packaging materials and devices, the SiC MCPM was designed to exhibit low thermal resistance which was modeled using three-dimensional finite-element analysis and experimentally verified to be 0.18 °C/W. A good agreement between the model and experiment was achieved. MCPMs were assembled and the gate leakage, drain leakage, on-state characteristics, and on-resistance were measured over temperature. To verify low parasitic design, the SiC MCPM was inserted into a boost converter configuration and the switching characteristics were investigated. Extremely low rise and fall times of 16.1 and 7.5 ns were observed, respectively. The boost converter demonstrated an efficiency of > 98.6% at 4.8 kW operating at a switching frequency of 250 kHz. In addition, a peak efficiency of 96.5% was achieved for a switching frequency of 1.2 MHz and output power of 3 kW.


2016 ◽  
Vol 2016 (CICMT) ◽  
pp. 000001-000005
Author(s):  
Soshu Kirihara

Abstract In a stereolithographic additive manufacturing (AM), two dimensional (2D) cross sectional patterns were created through photo polymerization by ultraviolet laser drawing on spread resin paste including ceramic nanoparticles, and three dimensional (3D) composite models were sterically printed by layer lamination through chemical bonding. An automatic collimeter was equipped with the laser scanner to adjust beam diameter. Fine or coarse beams could realize high resolution or wide area drawings, respectively. Metal and ceramic bulky components including dendritic networks were geometrically built by using stereolithographic AM. Geometric patterns with periodic, self-similar, graded and fluctuated arrangements were created by computer aided design, manufacture and evaluation (CAD/CAM/CAE) for effective modulations of energy and material flows through dielectric lattices in photonic crystals, porous electrodes in fuel cells and biological scaffolds in artificial bones.


2019 ◽  
Vol 53 (3) ◽  
pp. 197-205
Author(s):  
Kshitij Hemant Sabley ◽  
Usha Shenoy ◽  
Sujoy Banerjee ◽  
Pankaj Akhare ◽  
Ananya Hazarey ◽  
...  

Objective: To assess and compare the tensions and deformations (stresses and strains) generated after application of two types of forces (traction and torsion) in miniscrews of two different materials (titanium and stainless steel) placed at five different angulations. Materials and Methods: Three-dimensional models of the posterior maxillary area and the mini-implants were constructed using computer-aided design software program (CATIA P3 V5-6 R2015 B26 / 2016; Dassault Systèmes). Titanium and stainless steel materials were used for miniscrews. The area constructed was in between the maxillary second premolar and first molar. The models with mini-implants were inserted at five different angulations (30°, 45°, 60°, 75° and 90°). Torsional and tractional forces were applied on these implants, and the models were solved using ANSYS 10.0. Stress generated in implant and in the cortical and cancellous bones was evaluated and compared at all the five angulations. Results: Stress generated in stainless steel mini-implant during torsional and linear force application was less when compared with titanium mini-implant. Also, stress generated in implants of both materials increased as the angle increased from 30° to 90°. Difference in stress generated by stainless steel implant in the cortical bone for both linear and torsional forces was less when compared with titanium implant, whereas for cancellous bone, the difference was insignificant at all the angles. Conclusion: Irrespective of angles, difference in stress generated in stainless steel implants and titanium implants for both the forces was not significant, and hence, stainless steel implants can be used effectively in a clinical setting.


Author(s):  
Khaled E. Ahmed

The potential applications of computer-aided design/computer-aided manufacturing (CAD/CAM) and intraoral scanning exceed the delivery of standard prosthodontic interventions. The aim of this study was to clinically present a developed assessment technique, that relies on the use of sequential intraoral scanning, three-dimensional superimposition, and 2D and 3D deviation analyses based on a standardised protocol, as an auxiliary tool in monitoring dimensional changes of residual ridge post-extraction with a follow-up period of four months.


Author(s):  
Marcus Gamino ◽  
Samuel Abankwa ◽  
Raresh Pascali

A general assumption in performing vortex-induced vibration (VIV) analysis of pipeline free spans is both ends of the free span are fixed and/or pinned in order to simplify computational simulations; however, DNV Recommended Practice F105 states that these boundary conditions must adequately represent the pipe-soil interaction and the continuality of the pipeline. A computational methodology is developed to determine the effects of pip-soil interaction at the ends of a free span. Three-dimensional fluid-structure interaction (FSI) simulations are performed by coupling the computational fluid dynamics (CFD) codes from STAR-CCM+ with the finite element analysis (FEA) codes from ABAQUS. These FSI simulations in combination with separate coupled Eulerian-Lagrangian (CEL) simulations are modeled to mimic real word conditions by setting up boundary conditions to factor in the effects of pipe-soil interaction at the ends of the span. These simulations show a mitigation of overall stresses to the free spans; as a result, the integration of pipe-soil interaction in free span assessment may prove cost effective in the prevention of unnecessary corrective action.


2012 ◽  
Vol 21 (6) ◽  
pp. 440-450 ◽  
Author(s):  
Thamer Yousif Marghalani ◽  
Mohamed Tharwat Hamed ◽  
Mohamed Abdelmageed Awad ◽  
Ghada Hussein Naguib ◽  
Ahmed Fouad Elragi

2021 ◽  
Vol 10 ◽  
Author(s):  
Sian Chen ◽  
Chenbin Chen ◽  
Yuanbo Hu ◽  
Ce Zhu ◽  
Xiaozhi Luo ◽  
...  

Gastric cancer (GC) is one of the most common malignancies with high mortality and substantial morbidity. Although the traditional treatment strategies for GC revolve around surgery, radiotherapy, and chemotherapy, none have been able to optimally treat most affected patients. To improve clinical outcomes and overcome potential GC resistance, we established a three-dimensional (3D) culturing platform that accurately predicts drug responses in a time- and cost-effective manner. We collected tumor tissues from patients following surgeries and cultured them for 3 days using our protocol. We first evaluated cell proliferation, viability, and apoptosis using the following markers: Ki67 and cleaved caspase 3 (Cas3). We demonstrated that cell viability was maintained for 72 h in culture and that the tumor microenvironments and vascular integrities of the tissues were intact throughout the culture period. We then administered chemotherapeutics to assess drug responses and found differential sensitivity across different patient-derived tissues, enabling us to determine individualized medication plans. Overall, our study validated this rapid, cost-effective, scalable, and reproducible protocol for GC tissue culture that can be employed for drug response assessments. Our 3D culture platform paves a new way for personalized medication in GC and other tumors and can greatly impact future oncological research.


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