Design Concept of Marine GenSet Engines

1995 ◽  
Vol 32 (04) ◽  
pp. 297-304
Author(s):  
O. Schnohr
Keyword(s):  
Combustion Process ◽  
Cooling Water ◽  
Design Concept ◽  
Design Parameters ◽  
Diesel Generator ◽  
Operational Conditions ◽  
Cargo Handling ◽  
Generating Sets ◽  
Cost Efficient ◽  
Marine Applications

Experience gained from the MAN B&W Holeby heavy fuel burning marine GenSets is described. This is the most widely used diesel generator engine for marine applications within its power range. The combustion process is based on design parameters and features which enable operating and maintenance costs to be kept low even when the cheapest types of heavy fuel are used. The paper outlines how the design concept also results in very low emission figures, which will permit ship-owners to observe prospective NOx regulations at no extra expense. The Uni-concept, which features the combined installation of the two-stroke low speed propulsion engine and the generating sets, sharing a common fuel system (Uni-fuel Concept), common simplified cooling water systems, starting air installation, etc., is explained. This concept enables the shipyard to select the simplest and most cost-efficient engine installation for the vessel. The technology used for the unrestricted low load operation of the engine is presented, and an outline is given of the special operational conditions, and of the great electrical load fluctations that prevail, for instance during the loading and unloading of the vessel by means of its own cargo-handling equipment.

Towards the Design of Cost-efficient Generic Register Using Quantum-dot Cellular Automata

2020 ◽  
Vol 10 (4) ◽  
pp. 534-547
Author(s):  
Chiradeep Mukherjee ◽  
Saradindu Panda ◽  
Asish K. Mukhopadhyay ◽  
Bansibadan Maji
Keyword(s):  
Cellular Automata ◽  
Quantum Dot ◽  
Power Dissipation ◽  
Cmos Technology ◽  
Oxide Semiconductor ◽  
Digital Data ◽  
Design Parameters ◽  
Flip Flop ◽  
Quantum Dot Cellular Automata ◽  
Cost Efficient

Background: The advancement of VLSI in the application of emerging nanotechnology explores quantum-dot cellular automata (QCA) which has got wide acceptance owing to its ultra-high operating speed, extremely low power dissipation with a considerable reduction in feature size. The QCA architectures are emerging as a potential alternative to the conventional complementary metal oxide semiconductor (CMOS) technology. Experimental: Since the register unit has a crucial role in digital data transfer between the electronic devices, such study leading to the design of cost-efficient and highly reliable QCA register is expected to be a prudent area of research. A thorough survey on the existing literature shows that the generic models of Serial-in Serial Out (SISO), Serial-in-Parallel-Out (SIPO), Parallel-In- Serial-Out (PISO) and Parallel-in-Parallel-Out (PIPO) registers are inadequate in terms of design parameters like effective area, delay, O-Cost, Costα, etc. Results: This work introduces a layered T gate for the design of the D flip flop (LTD unit), which can be broadly used in SISO, SIPO, PISO, and PIPO register designs. For detection and reporting of high susceptible errors and defects at the nanoscale, the reliability and defect tolerant analysis of LTD unit are also carried out in this work. The QCA design metrics for the general register layouts using LTD unit is modeled. Conclusion: Moreover, the cost metrics for the proposed LTD layouts are thoroughly studied to check the functional complexity, fabrication difficulty and irreversible power dissipation of QCA register layouts.

scholarly journals Design, Manufacturing and Test of CFRP Front Hood Concepts for a Light-Weight Vehicle

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1374
Author(s):  
Paul Bere ◽  
Mircea Dudescu ◽  
Călin Neamțu ◽  
Cătălin Cocian
Keyword(s):  
Automotive Industry ◽  
Design Concept ◽  
Torsional Stiffness ◽  
Material Structure ◽  
Black Metal ◽  
Design Concepts ◽  
Metal Design ◽  
Body Components ◽  
Cost Efficient ◽  
Transversal Stiffness

Composite materials are very often used in the manufacture of lightweight parts in the automotive industry, manufacturing of cost-efficient elements implies proper technology combined with a structural optimization of the material structure. The paper presents the manufacturing process, experimental and numerical analyses of the mechanical behavior for two composite hoods with different design concepts and material layouts as body components of a small electric vehicle. The first model follows the black metal design and the second one is based on the composite design concept. Manufacturing steps and full details regarding the fabrication process are delivered in the paper. Static stiffness and strain values for lateral, longitudinal and torsional loading cases were investigated. The first composite hood is 254 times lighter than a similar steel hood and the second hood concept is 22% lighter than the first one. The improvement in terms of lateral stiffness for composite hoods about a similar steel hood is for the black metal design concept about 80% and 157% for the hood with a sandwich structure and modified backside frame. Transversal stiffness is few times higher for both composite hoods while the torsional stiffness has an increase of 62% compared to a similar steel hood.

Thermodynamic Performance Optimization of Reciprocating Internal Combustion (IC) Engines

2008 ◽  
Author(s):  
George A. Adebiyi ◽  
Kalyan K. Srinivasan ◽  
Charles M. Gibson
Keyword(s):  
Performance Optimization ◽  
Combustion Process ◽  
Design Parameters ◽  
Second Law ◽  
Ic Engine ◽  
Thermodynamic Performance ◽  
Second Law Analysis ◽  
Compression And Expansion ◽  
Dual Cycle ◽  
Ic Engines

Reciprocating IC engines are traditionally modeled as operating on air standard cycles that approximate indicator diagrams obtained in experiments on real engines. These indicator diagrams can best be approximated by the dual cycle for both gasoline and diesel engines. Analysis of air standard cycles unfortunately fails to capture second law effects such as exergy destruction due to the irreversibility of combustion. Indeed, a complete thermodynamic study of any process requires application of both the first and second laws of thermodynamics. This article gives a combined first and second law analysis of reciprocating IC engines in general with optimization of performance as primary goal. A practical dual-like cycle is assumed for the operation of a typical reciprocating IC engine and process efficiencies are assigned to allow for irreversibilities in the compression and expansion processes. The combustion process is modeled instead of being replaced simply by a heat input process to air as is common in air standard cycle analysis. The study shows that performance of the engine can indeed be optimized on the basis of geometrical design parameters such as the compression ratio as well as the air-fuel ratio used for the combustion.

scholarly journals Development of a Novel Double-Ring Deployable Mesh Antenna

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Yan Xu ◽  
Fuling Guan ◽  
Xian Xu ◽  
Hongjian Wang ◽  
Yao Zheng
Keyword(s):  
Low Frequency ◽  
Design Concept ◽  
Design Parameters ◽  
Accuracy Measurement ◽  
Double Ring ◽  
Reflective Surface ◽  
Final Design ◽  
Geometric Relationship ◽  
Relationship Of ◽  
Adjustment Test

This paper addresses a type of deployable mesh antenna consisting of the double-ring deployable truss edge frame and the cable net reflector. The structural design concept of the deployable antennas is presented. The deployable truss is designed and the geometric relationship of each strut length is formulated. Two types of radial truss elements are described and compared. The joint pattern and the active cables of the final design concept are determined. The pattern of the cable net is the three-orientation grid. Two connection schemes between the reflector and the deployable edge frame are investigated. The design parameters and the shape adjustment mechanism of this cable net are determined. The measurement test technologies of the antennas on the ground including test facilities, deployment test, and measurement and adjustment test are proposed. The antenna patterns are analyzed based on the real surfaces of the reflector obtained by the reflective surface accuracy measurement. The tests and analytic results indicated that the accuracy of the reflective surface is high and is suitable for low-frequency communication.

Effects of the Injection Parameters on the Emissions of a Heavy Duty Diesel Engine

2009 ◽  
Author(s):  
M. Yılmaz ◽  
M. Zafer Gul ◽  
Y. Yukselenturk ◽  
B. Akay ◽  
H. Koten
Keyword(s):  
Diesel Engine ◽  
Direct Injection ◽  
Combustion Process ◽  
Design Parameters ◽  
Combustion Model ◽  
Particulate Emissions ◽  
Multiphase Model ◽  
Heavy Duty ◽  
Flow Development ◽  
Air Motion

It is estimated by the experts in the automotive industry that diesel engines on the transport market should increase within the years to come due to their high thermal efficiency coupled with low carbon dioxide (CO2) emissions, provided their nitrogen oxides (NOx) and particulate emissions are reduced. At present, adequate after-treatments, NOx and particulates matter (PM) traps are developed and industrialized with still concerns about fuel economy, robustness, sensitivity to fuel sulfur and cost because of their complex and sophisticated control strategy. New combustion processes focused on clean diesel combustion are investigated for their potential to achieve near zero particulate and NOx emissions. Their main drawbacks are increased level of unburned hydrocarbons (HC) and carbon monoxide (CO) emissions, combustion control at high load and limited operating range and power output. In this work, cold flow simulations for a single cylinder of a nine-liter (6 cylinder × 1.5 lt.) diesel engine have been performed to find out flow development and turbulence generation in the piston-cylinder assembly. In this study, the goal is to understand the flow field and the combustion process in order to be able to suggest some improvements on the in-cylinder design of an engine. Therefore combustion simulations of the engine have been performed to find out flow development and emission generation in the cylinder. Moreover, the interaction of air motion with high-pressure fuel spray injected directly into the cylinder has also been carried out. A Lagrangian multiphase model has been applied to the in-cylinder spray-air motion interaction in a heavy-duty CI engine under direct injection conditions. A comprehensive model for atomization of liquid sprays under high injection pressures has been employed. The combustion is modeled via a new combustion model ECFM-3Z (Extended Coherent Flame Model) developed at IFP. Finally, a calculation on an engine configuration with compression, spray injection and combustion in a direct injection Diesel engine is presented. Further investigation has also been performed in-cylinder design parameters in a DI diesel engine that result in low emissions by effect of high turbulence level. The results are widely in agreement qualitatively with the previous experimental and computational studies in the literature.

Recent Advances in On-disk Viscous Micropumps

2009 ◽  
Vol 6 (4) ◽  
pp. 240-249 ◽  
Author(s):  
Ala'aldeen T. Al-Halhouli
Keyword(s):  
Experimental Tests ◽  
Quantitative Comparison ◽  
Design Parameters ◽  
Flow Rates ◽  
Operational Conditions ◽  
Recent Advances ◽  
Viscous Micropump ◽  
Single Disk ◽  
Analytical Development ◽  
Spiral Channel

This work surveys recent advances of experimental and analytical development progress of the on-disk viscous micro-pumps: spiral channel, single disk, and double disk micropumps. These micropumps have attractive advantages for handling particle-laden fluids which make them key components in laboratory-on-a-chip applications. This study builds upon existing reviews and reports on the on-disk viscous micropump concept and analytical and experimental tests. It also presents a general analytical solution that estimates for the combined effect of operational and geometrical design parameters on the flow performance of on-disk viscous micropumps. This model enables microfluidic systems designers and developers to predict flow rates and pressures according to certain geometrical or operational conditions. Quantitative comparison and verifications are provided in tabular and graphical forms.

scholarly journals Potential of Wind Energy in Albania and Kosovo: Equity Payback and GHG Reduction of Wind Turbine Installation

2015 ◽  
Vol 4 (1) ◽  
pp. 11-19
Author(s):  
Mevlan Qafleshi ◽  
Driton R. Kryeziu ◽  
Lulezime Aliko
Keyword(s):  
Wind Energy ◽  
Wind Turbine ◽  
Power Plants ◽  
Combustion Process ◽  
Energy Generation ◽  
Base Case ◽  
Climate Data ◽  
Diesel Generator ◽  
Ghg Reduction ◽  
The Impact

The energy generation in Albania is completely from the hydropower plants. In terms of GHG emissions this is 100% green. In Kosovo 97% of energy is generated from lignite fired power plants. Apart the energy generation, the combustion process emits around 8000 ktCO2/yr and 1.5 Mt of ash in the form of fly and bottom ash. In both countries there is no MWh power generated from wind energy, i.e. this energy source is not utilized. Here, a proposed project for five locations in Albania and Kosovo has been analyzed in detail with the aim of installing a 1kW wind turbine off-grid. The method of study is based on the application of RETScreen International program software. This proposed model is intended to replace a base case- a diesel generator with installed capacity 7kW.  The locations are selected three in Albania: Vlora, Korça and Elbasan, and two in Kosovo: Prishtina and Prizren. All are in different altitudes. By the calculation of RETScreen program, it has been analyzed the feasibility of the proposed projects by installing a wind turbine at hub’s height 20m. The climate data for each location were retrieved by the RETScreen program from NASA. Generally, the calculation of financial parameters for the investments came out to be positive, the impact of GHG reduction very significant. A 5500 USD investment for the implementation of proposed case showed an equity payback time of 2-3 yrs and GHG reduction of 2.2 tCO2/yr. The electricity delivery to load only from this 1 KW wind turbine resulted to be between 1.6-17 MWh/yr.

Wet Shape Memory Alloy Actuated Robotic Heart

2009 ◽  
Author(s):  
Joel Ertel ◽  
Stephen Mascaro
Keyword(s):  
Shape Memory Alloy ◽  
Theoretical Analysis ◽  
Shape Memory ◽  
Preliminary Analysis ◽  
Design Concept ◽  
Design Parameters ◽  
Sma Actuators ◽  
Fluid Analysis ◽  
Cold Fluid ◽  
Simulation And Experiment

This paper presents a conceptual design and preliminary analysis for a biomimetic robotic heart. The purpose of the robotic heart is to distribute hot and cold fluid to robotic muscles composed of wet shape-memory alloy (SMA) actuators. The robotic heart is itself powered by wet SMA actuators. A heart design concept is proposed and the feasibility of self-sustaining motion is investigated through simulation and experiment. The chosen design employs symmetric pumping chambers for hot and cold fluid. Analysis of this design concept shows that there exists a range of design parameters that will allow the heart to output more fluid than it uses. Additionally, it is shown that the heartbeat rate decreases as the system increases in size, and that the number of actuators and their length limit the power output of the pump. Experimental results from a prototype heart agree with the predicted trends from theoretical analysis and simulation.

ARMA Model for Turbine and Compressor Clearance Forecasting

2010 ◽  
Author(s):  
Huageng Luo ◽  
George Ghanime ◽  
Liping Wang
Keyword(s):  
Arma Model ◽  
Design Parameters ◽  
Computationally Efficient ◽  
Detailed Model ◽  
Reduced Order ◽  
Operational Conditions ◽  
Turbine Efficiency ◽  
Modeling And Prediction ◽  
Efficiency And Effectiveness ◽  
Arma Modeling

In turbo machinery, clearance (the distance between the turbine or compressor blade tip to the casing) at high-pressure stages is one of the key design parameters to measure the turbine efficiency and effectiveness. Thus, appropriate modeling and prediction of the clearance under operational conditions is very important. If the clearance can be actively controlled, the turbine manufacturers get even more competitive advantages. For turbine design purpose, detailed physics based model is usually available. However, this kind of detailed model is not suitable for on-line prediction due to heavy computational requirements. Instead, a reduced order model based on the first order physics is used. Usually, the available reduced order models are computationally efficient, but they can hardly reach the accuracy desired by control engineers. In this paper, we applied an ARMA modeling technique for the reduced order clearance modeling and prediction. Typical turbine cycle operation data were used to build the ARMA model first. The built model is then used to predict other operations of the same unit, as well as other units of the same family.

Design of a Spacer Grid Using Axiomatic Design

2002 ◽  
Author(s):  
K. N. Song ◽  
B. S. Kang ◽  
K. H. Yoon ◽  
S. K. Choi ◽  
G. J. Park
Keyword(s):  
Cooling Water ◽  
Axiomatic Design ◽  
Axiomatic Approach ◽  
Design Parameters ◽  
Independence Axiom ◽  
Functional Requirements ◽  
Spacer Grid ◽  
Element Analysis ◽  
Detailed Design ◽  
Analysis And Design

Recently, much attention has been focused on the design of the fuel assemblies in the Pressurized Light Water Reactor (PLWR). The spacer grid is one of the main structural components in a fuel assembly. It supports fuel rods, guides cooling water, and maintains geometry from the external impact loads. In this research, a new shape of the spacer grid is designed by the axiomatic approach. The Independence Axiom is utilized for the design. For the conceptual design, functional requirements (FRs) are defined and corresponding design parameters (DPs) are found to satisfy FRs in sequence. Overall configuration and shapes are determined in this process. Detailed design is carried out based on the result of the axiomatic design. For the detailed design, the system performances are evaluated by using linear and nonlinear finite element analysis. The dimensions are determined by optimization. Some commercial codes are utilized for the analysis and design.

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