Preliminary Design Tool for the Performance Prediction of High Speed Planing Craft in Irregular Seas

2013 ◽  
Author(s):  
E M Fay ◽  
Keyword(s):  
Performance Prediction ◽  
High Speed ◽  
Design Tool ◽  
Preliminary Design ◽  
Planing Craft

scholarly journals Numerical Simulation of Seakeeping Performance on the Preliminary Design of a Semi-Planing Craft

2019 ◽  
Vol 7 (7) ◽  
pp. 199 ◽  
Author(s):  
Yu-Hsien Lin ◽  
Chia-Wei Lin
Keyword(s):  
High Speed ◽  
Route Planning ◽  
Test Cases ◽  
Preliminary Design ◽  
Sea State ◽  
Planing Craft ◽  
High Speeds ◽  
Motion Responses ◽  
Seakeeping Performance ◽  
The Difference

This study established a seakeeping program to evaluate the motion responses of a high speed semi-planing craft and to develop a database for future route planning. A series 62 mono-hull was chosen for the test cases, comparing seakeeping performances with full-scale on-board measurements. The statistical results were obtained using spectral analysis, which combines the International Towing Tank Conference (ITTC) spectrum with the response amplitude operator (RAO) responses of each wave heading for a given sailing speed. The speed polar diagram was made to illustrate five degree-of-freedom (DOF) motion responses between sailing speeds and wave heading angles in a particular sea state. Although the craft has different trim angles at high speeds (because of dynamic lift) under various loading and draft conditions, this study only investigated the trim angles of 0° (even keel), 1° by the stern, and 2° by the stern, to understand the difference between their seakeeping performances. The results in this study provide a useful guideline for evaluating operational regulations and safety for high speed semi-planing crafts in the future.

Use of Athena Vortex Lattice for Preliminary Hydrofoil Design

2015 ◽  
Author(s):  
Katelynne R. Burrell ◽  
Joshua P. Sykes ◽  
Timothy B. Dewhurst ◽  
Zhaohui Qin
Keyword(s):  
High Speed ◽  
Vortex Lattice ◽  
Design Tool ◽  
Preliminary Design ◽  
Reference Guide ◽  
The Past ◽  
Lifting Surfaces ◽  
Lift And Drag ◽  
Design Options ◽  
Short Time

The purpose of this paper is to demonstrate the extent to which the Athena Vortex Lattice program (AVL) is useful in the design of a hydrofoil system for a solar boat. Cedarville University has won the Solar Splash Collegiate World Championship of Solar Boating 8 times in the past 12 years, and was the top university in the Top Class of the 2012 DONG Energy Solar Challenge in the Netherlands. The three main events of the Solar Splash Competition are the high-speed Slalom and Sprint events, and the longer Endurance event. In the past Cedarville has attempted to design and use hydrofoils for the Endurance event without success. Computational Fluid Dynamics (CFD) analysis for a hydrofoil system was conducted by Neola Putnam (2013 team member) using ANSYS’s CFD software, Fluent. Putnam worked with single phase flow modeling 3D hydrofoils. Fluent analysis can be a long and complicated process requiring hours of meshing followed by hours of CPU time for analysis. AVL, as an alternative, is a less complicated program allowing for simple generation of a geometry file. This program also takes a comparatively short time to analyze the imported geometry file. Thus, if AVL reliably predicts lift and drag, it could be used as a preliminary design tool to quickly assess various design options. AVL is a program which models lifting surfaces as vortex lattice sheets to determine the flight characteristics of the surface. The program is written in Fortran and is an inviscid solver. The AVL3.30 User Primer is a reference guide on how to use the program and was used extensively by the authors of this paper when learning to use AVL. Cedarville University also partnered with the company Sea Land Aire Technologies Inc.in Jackson Michigan for aid in using AVL as a design tool. The tool was recommended to Cedarville University by Sea Land Aire as a product which might be of interest to our team in the design of a hydrofoil system. AVL is potentially beneficial to the Cedarville University Solar Boat team in the preliminary design phase of a hydrofoil system. The content of this paper demonstrates the correlation between results from AVL and Fluent analysis for a 2D NACA 4412 foil. Secondly, the paper demonstrates comparable results from AVL for 3Danalysiswith published experimental results. The following sections discuss the use of AVL as a preliminary design tool, and the overall recommendation of the authors as to further use of AVL by Cedarville University in the design of a hydrofoil system.

A Hydrodynamic Preliminary Design Optimization Framework for High Speed Planing Craft

2012 ◽  
Vol 56 (1) ◽  
pp. 35-47 ◽  
Author(s):  
Ahmad F. Mohamad Ayob ◽  
Tapabrata Ray ◽  
Warren Smith
Keyword(s):  
Design Optimization ◽  
High Speed ◽  
Preliminary Design ◽  
Planing Craft ◽  
Optimization Framework

A Hydrodynamic Preliminary Design Optimization Framework for High Speed Planing Craft

2012 ◽  
Vol 56 (01) ◽  
pp. 35-47
Author(s):  
Ahmad F. Mohamad Ayob ◽  
Ahmad F. Mohamad Ayob ◽  
Tapabrata Ray ◽  
Warren Smith
Keyword(s):  
Design Optimization ◽  
High Speed ◽  
Ship Design ◽  
Design Stage ◽  
Preliminary Design ◽  
Planing Craft ◽  
Performance Targets ◽  
Optimization Framework ◽  
Design Variables ◽  
Performance Estimates

Ship design optimization in preliminary design stage aims to identify optimum vessel dimensions based on performance targets and design constraints simultaneously. Although vast amount of designs have been generated and evaluated since the application of optimization approaches to ship design, only a few of such designs have been built or "dissected" to gain a deeper understanding as to why such designs tend to be optimal. In this paper an optimization framework is introduced for the design of high speed planing craft, which consists of a geometry module, standard performance estimates, and a suite of state-of-the-art optimization algorithms. Single and multiobjective optimization problem formulations are solved using the framework. Designs identified through the process of optimization are further analyzed to uncover relationships among the design variables that lead to better designs. An important contribution of this paper is to illustrate the steps involved in deriving pseudo performance estimates and their utility in the context of preliminary design where such relationships can be effectively and efficiently used to sieve through a large number of designs.

Design and Implementation of an Efficient Parallel LFSR Architecture for Wireless Communication Systems

2019 ◽  
Vol 14 ◽  
Author(s):  
A. Suresh Babu ◽  
B. Anand
Keyword(s):  
Wireless Communication ◽  
Power Consumption ◽  
Low Power ◽  
Communication Systems ◽  
High Speed ◽  
Design Tool ◽  
Shift Register ◽  
Linear Feedback ◽  
Wireless Communication Systems ◽  
Coverage Area

: A Linear Feedback Shift Register (LFSR) considers a linear function typically an XOR operation of the previous state as an input to the current state. This paper describes in detail the recent Wireless Communication Systems (WCS) and techniques related to LFSR. Cryptographic methods and reconfigurable computing are two different applications used in the proposed shift register with improved speed and decreased power consumption. Comparing with the existing individual applications, the proposed shift register obtained >15 to <=45% of decreased power consumption with 30% of reduced coverage area. Hence this proposed low power high speed LFSR design suits for various low power high speed applications, for example wireless communication. The entire design architecture is simulated and verified in VHDL language. To synthesis a standard cell library of 0.7um CMOS is used. A custom design tool has been developed for measuring the power. From the results, it is obtained that the cryptographic efficiency is improved regarding time and complexity comparing with the existing algorithms. Hence, the proposed LFSR architecture can be used for any wireless applications due to parallel processing, multiple access and cryptographic methods.

Using CFD to Enhance the Preliminary Design of High-Pressure Steam Turbines

2013 ◽  
Author(s):  
Juri Bellucci ◽  
Federica Sazzini ◽  
Filippo Rubechini ◽  
Andrea Arnone ◽  
Lorenzo Arcangeli ◽  
...  
Keyword(s):  
High Pressure ◽  
Steam Turbine ◽  
Design Tool ◽  
Tip Clearance ◽  
Large Set ◽  
Preliminary Design ◽  
Steam Turbines ◽  
High Pressure Steam ◽  
Wide Range ◽  
Pressure Steam

This paper focuses on the use of the CFD for improving a steam turbine preliminary design tool. Three-dimensional RANS analyses were carried out in order to independently investigate the effects of profile, secondary flow and tip clearance losses, on the efficiency of two high-pressure steam turbine stages. The parametric study included geometrical features such as stagger angle, aspect ratio and radius ratio, and was conducted for a wide range of flow coefficients to cover the whole operating envelope. The results are reported in terms of stage performance curves, enthalpy loss coefficients and span-wise distribution of the blade-to-blade exit angles. A detailed discussion of these results is provided in order to highlight the different aerodynamic behavior of the two geometries. Once the analysis was concluded, the tuning of a preliminary steam turbine design tool was carried out, based on a correlative approach. Due to the lack of a large set of experimental data, the information obtained from the post-processing of the CFD computations were applied to update the current correlations, in order to improve the accuracy of the efficiency evaluation for both stages. Finally, the predictions of the tuned preliminary design tool were compared with the results of the CFD computations, in terms of stage efficiency, in a broad range of flow coefficients and in different real machine layouts.

High Speed FPGA Based 128-bit Advance Encryption Standard (AES)

2021 ◽  
Vol 11 ◽  
Author(s):  
Ibrahem M. T. Hamidi ◽  
Farah S. H. Al-aassi
Keyword(s):  
High Throughput ◽  
Field Programmable Gate Array ◽  
High Speed ◽  
Design Tool ◽  
Advanced Encryption Standard ◽  
Clock Frequency ◽  
Advance Encryption Standard ◽  
Field Programmable ◽  
Internal Component ◽  
Gate Array

Aim: Achieve high throughput 128 bits FPGA based Advanced Encryption Standard. Background: Field Programmable Gate Array (FPGA) provides an efficient platform for design AES cryptography system. It provides the capability to control over each bit using HDL programming language such as VHDL and Verilog which results an output speed in Gbps rang. Objective: Use Field Programmable Gate Array (FPGA) to design high throughput 128 bits FPGA based Advanced Encryption Standard. Method: Pipelining technique has used to achieve maximum possible speed. The level of pipelining includes round pipelining and internal component pipelining where number of registers inserted in particular places to increase the output speed. The proposed design uses combinatorial logic to implement the byte substitution. The s-box implemented using composed field arithmetic with 7 stages of pipelining to reduce the combinatorial logic level. The presented model has implemented using VHDL in Xilinix ISETM 14.4 design tool. Result: The achieved results were 18.55 Gbps at a clock frequency of 144.96 MHz and area of 1568 Slices in Spartan3 xc3s1000 hardware. Conclusion: The results show that the proposed design reaches a high throughput with acceptable area usage compare with other designs in the literature.

System Design and Modeling of a Thermally Activated Reconfigurable Wing

2010 ◽  
Author(s):  
Richard Beblo ◽  
Darrel Robertson ◽  
James Joo ◽  
Brian Smyers ◽  
Gregory Reich
Keyword(s):  
Thermal Energy ◽  
High Speed ◽  
Frictional Heating ◽  
Mechanical Analysis ◽  
Design Tool ◽  
System Level ◽  
Morphing Aircraft ◽  
Thermal Actuation ◽  
Short Period ◽  
Reconfigurable Structures

Reconfigurable structures such as morphing aircraft generally require an on board energy source to function. Frictional heating during the high speed deployment of a blunt nosed low speed reconnaissance air vehicle can provide a large amount of thermal energy during a short period of time. This thermal energy can be collected, transferred, and utilized to reconfigure the deployable aircraft. Direct utilization of thermal energy has the ability to significantly decrease or eliminate the losses associated with converting thermal energy to other forms, such as electric. The following work attempts to describe possible system designs and components that can be utilized to transfer the thermal energy harvested at the nose of the aircraft during deployment to internal components for direct thermal actuation of a reconfigurable wing structure. A model of a loop heat pipe is presented and used to predict the time dependant transfer of energy. Previously reported thermal profiles of the nose of the aircraft calculated based on trajectory and mechanical analysis of the actuation mechanism are reviewed and combined with the model of the thermal transport system providing a system level feasibility investigation and design tool. The efficiency, implementation, benefits, and limitations of the direct use thermal system are discussed and compared with currently utilized systems.

Transient Analysis and Performance Prediction of a Solid Adsorption Solar Refrigerator

Solar Energy ◽  
2005 ◽  
Author(s):  
Emmanuel E. Anyanwu ◽  
Nnamdi V. Ogueke
Keyword(s):  
Performance Prediction ◽  
Transient Analysis ◽  
Adsorption Process ◽  
Design Tool ◽  
Coefficient Of Performance ◽  
Collector Plate ◽  
Tube Arrangement ◽  
And Performance ◽  
Mass Transfers ◽  
The Mathematical Model

The transient analysis and performance prediction of a solid adsorption solar refrigerator, using activated carbon/methanol adsorbent/adsorbate pair are presented. The mathematical model is based on the thermodynamics of the adsorption process, heat transfer in the collector plate/tube arrangement, and heat and mass transfers within the adsorbent/adsorbate pair. Its numerical model developed from finite element transformation of the resulting equations computes the collector plate and tube temperatures to within 5°C. The condensate yield and coefficient of performance, COP were predicted to within 5% and 9%, respectively. The resulting evaporator water temperature was also predicted to within 4%. Thus the model is considered a useful design tool for the refrigerator to avoid costly experimentation.

scholarly journals Quasi-two-dimensional approximation for numerical simulation of flows in engine ducts

2019 ◽  
Author(s):  
V. Vlasenko ◽  
A. Shiryaeva
Keyword(s):  
High Speed ◽  
Fuel Injection ◽  
Three Dimensional ◽  
Preliminary Design ◽  
Two Dimensional ◽  
Combustion Chambers ◽  
New Approach ◽  
One Dimensional ◽  
Dimensional Approximation ◽  
3D Flows

New quasi-two-dimensional (2.5D) approach to description of three-dimensional (3D) flows in ducts is proposed. It generalizes quasi-one-dimensional (quasi-1D, 1.5D) theories. Calculations are performed in the (x; y) plane, but variable width of duct in the z direction is taken into account. Derivation of 2.5D approximation equations is given. Tests for verification of 2.5D calculations are proposed. Parametrical 2.5D calculations of flow with hydrogen combustion in an elliptical combustor of a high-speed aircraft, investigated within HEXAFLY-INT international project, are described. Optimal scheme of fuel injection is found and explained. For one regime, 2.5D and 3D calculations are compared. The new approach is recommended for use during preliminary design of combustion chambers.

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