scholarly journals A comparative review of the resistance of a 37,000 dwt Chemical Tanker based on experimental tests and calculations

2020 ◽  
Vol 1 ◽  
pp. 59-66
Author(s):  
Liviu Crudu ◽  
Radu Bosoancă ◽  
Dan Obreja
Keyword(s):  
Energy Efficiency ◽  
Experimental Tests ◽  
Full Scale ◽  
The Other ◽  
Towing Tank ◽  
Ship Resistance ◽  
Comparative Review ◽  
Cfd Applications ◽  
Energy Efficiency Design Index ◽  
Comparison Of The Results

The evaluation of ship resistance is of paramount importance having a decisive impact on the economic performances and efficiency depending on mission. If new IMO requirements through the Energy Efficiency Design Index (EEDI) are taken into account the necessity to have more and more accurate tools capable to consider the influences of different parameters became mandatory. The availability of towing tank facilities and the full scale trials are the practical means in order to be able to confirm the accuracy of theoretical formulations and to define the limits of CFD applications. Based on the results of the towing tank tests, a direct comparison with the results provided by classical methods and CFD computations can be systematically can be performed. On the other hand, the influences of the modifications operated on the fore part of the ship aretheoretically evaluated and compared with the towing tank results. Consequently, the paper is focused on the comparison of the results evaluated using different tools which have been carried out for a Chemical Tanker built by Constanta Shipyard Romania.

scholarly journals The Influence of Ice-Resistant Coatings Characteristics to the Energy Efficiency of Ice-Going Ships

2021 ◽  
Vol 320 ◽  
pp. 01007
Author(s):  
V.A. Veselov ◽  
M.V. Kitaev ◽  
P.O. Pastukhov ◽  
O.E. Surov
Keyword(s):  
Energy Efficiency ◽  
Friction Coefficient ◽  
Power Plant ◽  
Service Life ◽  
Frictional Resistance ◽  
Experimental Tests ◽  
Operating Conditions ◽  
The Other ◽  
Low Friction ◽  
Ice Navigation

The main purpose of ice-resistant coatings designed for icebreakers and ice navigation ships is the ability to protect of the ship’s hull in the most severe operating conditions. The special coatings certified by the Classification Societies for ice abrasion can provide this protection. These coatings allow to reduce the required thickness of the ship’s hull and reduce the construction weight of the ships. On the other hand, these coatings must have a low friction coefficient, which reduce the frictional resistance of the hull on ice and fuel consumption, increase the service life of the ship and power plant, reduce CO2 emissions into the atmosphere and affect to the operational and economic efficiency of the ship. In this paper, we present the results of experimental tests of friction coefficient on ice for various types of ice-resistant coatings and analysis the influence of ice-resistant coatings characteristics to the energy efficiency of ice-going ships.

Numerical Prediction of Car Tire Wear

2004 ◽  
Vol 32 (3) ◽  
pp. 164-186 ◽  
Author(s):  
H. Lupker ◽  
F. Cheli ◽  
F. Braghin ◽  
E. Gelosa ◽  
A. Keckman
Keyword(s):  
Mathematical Model ◽  
Friction And Wear ◽  
Experimental Tests ◽  
Full Scale ◽  
Numerical Prediction ◽  
The Other ◽  
Public Road ◽  
Tire Wear ◽  
Ecological Implications ◽  
Wear Law

Abstract Due to their many economic and ecological implications, the possibility to predict tire wear is of major importance to tire manufacturers, fleet owners and governments. Based on these observations, in 2000, a three-year project named TROWS (Tire and Road Wear and Slip assessment) was started. One of the TROWS objectives is to provide a tool able to numerically predict tire global wear as well as to qualitatively determine the wear distribution. The proposed methodology combines a mathematical model of the tire with an experimentally determined local friction and wear law. Thus, tire abrasion due to each single maneuver can be determined. Full-scale experimental tests were carried out with two Peugeot 406 cars on a public road course in Italy. Each car was equipped with a different set of tires: one car was equipped with four all-season tires (from now on called A tires) and the other car was equipped with four winter tires (from now on called B tires). Both sets of tires had a 195/65 R15 size. The collected data was used to validate the model. The methodology proved to give qualitatively good tire wear predictions.

scholarly journals To estimation of the Energy Efficiency Design Index (EEDI) for a ship with energy-saving wing devices

2021 ◽  
pp. 58-68
Author(s):  
К.В. Рождественский ◽  
М.Х. Зин
Keyword(s):  
Energy Efficiency ◽  
Aspect Ratio ◽  
Energy Saving ◽  
Wave Resistance ◽  
The Other ◽  
Large Aspect Ratio ◽  
Regular Waves ◽  
Strip Theory ◽  
Energy Efficiency Design Index ◽  
Oscillating Foil

В статье приводится оценка индекса проектной энергетической эффективности (EEDI) для судна с энергосберегающими крыльевыми устройствами на встречном регулярном волнении. Вначале на основе предыдущих работ авторов с применением линейной теории поперечных сечений определяются характеристики продольной (вертикальной и килевой) качки судна без крыльев, и такого же судна с крыльями большого удлинения, установленными на днище вблизи оконечностей с целью преобразования волновой энергии в дополнительную тягу. После определения параметров качки судна с крыльями как твердого тела, с применением теории Теодорсена колеблющегося профиля определяется средняя по периоду тяга энергосберегающих крыльевых элементов, совершающих поступательно-вращательные колебания. С другой стороны, в статье находится общее сопротивление системы «судно-крыльевые элементы». При этом применяется метод Холтропа в сочетании с теорие Бейкельмана-Герритсмы. Последняя дает возможность произвести оценку дополнительного волнового сопротивления по найденным параметрам продольной качки судна с крыльями и без крыльев. Затем оценивается значение индекса проектной энергетической эффективности (EEDI) контейнеровоза, снабженного энергосберегающими крыльями на встречном волнении. Исследование показывает, что установка на днище крыльевых элементов может использоваться как один из способов сокращения выброса углекислого газа и уменьшения в соответствии с требованиями Международной морской организации ИМО, значения индекса EEDI для репрезентативных морских условий. In this paper an estimation is presented of the Energy Efficiency Design Index (EEDI) for a ship with energy-saving wing devices in headwind regular waves. At first, based on previous works of the authors, there are determined with use of linear strip theory the characteristics of longitudinal (heaving and pitching) motions of a ship without wings and identical ship equipped with wings of large aspect ratio fitted on the bottom near extremities for the purpose of converting wave energy into additional thrust. After motions of the ship with wings as a solid boy are determined Theodorsen theory of oscillating foil is applied to calculate period averaged thrust of energy-saving wing elements, performing combined heave-pitch oscillations. On the other hand, the paper addresses the problem of determining overall drag of the “wing-plus-wings” system with use of Holtrop method combined with Beikelmann-Gerritsma theory. The latter enables carrying out an estimation of additional wave resistance based on the calculated parameters of the ship longitudinal motions with and without wings. Then follows an estimation of the EEDI for a containership equipped with wings in headwind regular waves. The study shows that fitting wing elements on the ship bottom can be seen as one of the methods for decreasing the magnitude of the EEDI for representative sea conditions as per requirements of the International Maritime Organization.

An Overview of Stepped Hull Performance Evaluation: Sea Trial Data vs Full-Scale CFD Simulation

2020 ◽  
Author(s):  
Luigi Vitiello ◽  
Simone Mancini ◽  
Rasul Niazmand Bilandi ◽  
Vincenzo Nappo
Keyword(s):  
Performance Evaluation ◽  
High Speed ◽  
Cfd Simulation ◽  
Experimental Tests ◽  
Trial Data ◽  
Full Scale ◽  
Cfd Simulations ◽  
Sea Trial ◽  
Comparison Of The Results ◽  
Real Scale

It is well known that the dynamic of the stepped hull in real scale is rather complex and it’s not easy to predict that using empirical or mathematical approaches, and by the numerical and experimental way as well. Moreover, there is a huge lack in the literature of data related to sea trials of the stepped hull. Furthermore, the reliability of full-scale CFD simulations is not widely proven and validated especially for high speed and planing hull. For these several reasons, in this paper, the authors are focused on the comparison of the results carried out from model experimental tests performed in the model basin, full-scale CFD simulations, and sea trial tests. The performed simulations in full-scale have been compared to the extrapolated experimental tests and the sea-trial results. Moreover, the dynamic trim angle and the dynamic wetted surface have been taken into account to assess the reliability of the full-scale simulation performed. The stepped hull considered is a Mito 31 outboard Rigid Inflatable Boat (RIB) built by MV Marine Srl Company.

Computational and experimental studies of the strength of full-scale samples of pipes with defects "metal loss" and "dent with groove"

2020 ◽  
Vol 10 (3) ◽  
pp. 226-233
Author(s):  
Dmitry A. Neganov ◽  
◽  
Victor M. Varshitsky ◽  
Andrey A. Belkin ◽  
◽  
...  
Keyword(s):  
Internal Pressure ◽  
Experimental Studies ◽  
Full Scale ◽  
The Other ◽  
Metal Loss ◽  
Calculation Methods ◽  
Reliable Operation ◽  
Sufficient Stability ◽  
Comparative Results ◽  
The Moment

The article contains the comparative results of the experimental and calculated research of the strength of a pipeline with such defects as “metal loss” and “dent with groove”. Two coils with diameter of 820 mm and the thickness of 9 mm of 19G steel were used for full-scale pipe sample production. One of the coils was intentionally damaged by machining, which resulted in “metal loss” defect, the other one was dented (by press machine) and got groove mark (by chisel). The testing of pipe samples was performed by applying static internal pressure to the moment of collapse. The calculation of deterioration pressure was carried out with the use of national and foreign methodical approaches. The calculated values of collapsing pressure for the pipe with loss of metal mainly coincided with the calculation experiment results based on Russian method and ASME B31G. In case of pipe with dent and groove the calculated value of collapsing pressure demonstrated greater coincidence with Russian method and to a lesser extent with API 579/ASME FFS-1. In whole, all calculation methods demonstrate sufficient stability of results, which provides reliable operation of pipelines with defects.

scholarly journals An Energy Consumption Approach to Estimate Air Emission Reductions in Container Shipping

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 278
Author(s):  
Ernest Czermański ◽  
Giuseppe T. Cirella ◽  
Aneta Oniszczuk-Jastrząbek ◽  
Barbara Pawłowska ◽  
Theo Notteboom
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Early Stage ◽  
Management Plan ◽  
Policy Formulation ◽  
Container Shipping ◽  
Shipping Industry ◽  
Emission Reductions ◽  
Energy Efficiency Design Index ◽  
Carbon Dioxide Co2

Container shipping is the largest producer of emissions within the maritime shipping industry. Hence, measures have been designed and implemented to reduce ship emission levels. IMO’s MARPOL Annex VI, with its future plan of applying Tier III requirements, the Energy Efficiency Design Index for new ships, and the Ship Energy Efficiency Management Plan for all ships. To assist policy formulation and follow-up, this study applies an energy consumption approach to estimate container ship emissions. The volumes of sulphur oxide (SOx), nitrous oxide (NOx), particulate matter (PM), and carbon dioxide (CO2) emitted from container ships are estimated using 2018 datasets on container shipping and average vessel speed records generated via AIS. Furthermore, the estimated reductions in SOx, NOx, PM, and CO2 are mapped for 2020. The empirical analysis demonstrates that the energy consumption approach is a valuable method to estimate ongoing emission reductions on a continuous basis and to fill data gaps where needed, as the latest worldwide container shipping emissions records date back to 2015. The presented analysis supports early-stage detection of environmental impacts in container shipping and helps to determine in which areas the greatest potential for emission reductions can be found.

Numerical Investigation of the Performance of a Roadside Safety Barrier Located Behind the Break Point of a Slope

2011 ◽  
Author(s):  
M. Mongiardini ◽  
J. D. Reid
Keyword(s):  
Numerical Investigation ◽  
Experimental Tests ◽  
Break Point ◽  
Full Scale ◽  
Crash Test ◽  
Construction Costs ◽  
Roadside Safety ◽  
The Road ◽  
Safety Barrier ◽  
Mechanically Stabilized

Numerical simulations allow engineers in roadside safety to investigate the safety of retrofit designs minimizing or, in some cases, avoiding the high costs related to the execution of full-scale experimental tests. This paper describes the numerical investigation made to assess the performance of a roadside safety barrier when relocated behind the break point of a 3H:1V slope, found on a Mechanically Stabilized Earth (MSE) system. A safe barrier relocation in the slope would allow reducing the installation width of the MSE system by an equivalent amount, thus decreasing the overall construction costs. The dynamics of a pick-up truck impacting the relocated barrier and the system deformation were simulated in detail using the explicit non-linear dynamic finite element code LS-DYNA. The model was initially calibrated and subsequently validated against results from a previous full-scale crash test with the barrier placed at the slope break point. After a sensitivity analysis regarding the role of suspension failure and tire deflation on the vehicle stability, the system performance was assessed when it was relocated into the slope. Two different configurations were considered, differing for the height of the rail respect to the road surface and the corresponding post embedment into the soil. Conclusions and recommendations were drawn based on the results obtained from the numerical analysis.

A Novel Window Type Air-Conditioner with Energy Recovering

2011 ◽  
Vol 250-253 ◽  
pp. 3021-3024
Author(s):  
Qing Hai Luo ◽  
Peng Fei Zhang ◽  
Xiu Fei Yang ◽  
Jun Zou
Keyword(s):  
Energy Efficiency ◽  
Heat Exchanger ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
The Other ◽  
The Novel ◽  
Air Conditioner ◽  
Efficiency Ratio ◽  
Additional Heat ◽  
Experimental Prototype

A novel window type air-conditioner with energy recovering was experimented. The experimental prototype can make fresh air exchange heat with exhaust air in an additional heat exchanger, which consist no additional moving parts. The EER (energy efficiency ratio) of the experimental air-conditioner (EAC) is increased by 17.4~37.3% than that of the original ordinary window type air-conditioner (OAC). On the other hand, the fresh air proportion of the EAC is increased by 20% or so than that of the OAC, so indoor air quality can be greatly improved via the EAC; however the indoor noise of the EAC is increased by 3.2 dB or so. The novel experimental prototype is of great significance for energy efficiency.

High temperature abatement of acid gases from waste incineration. Part I: Experimental tests in full scale plants

2015 ◽  
Vol 36 ◽  
pp. 98-105 ◽  
Author(s):  
Laura Biganzoli ◽  
Gaia Racanella ◽  
Lucia Rigamonti ◽  
Roberto Marras ◽  
Mario Grosso
Keyword(s):  
High Temperature ◽  
Experimental Tests ◽  
Waste Incineration ◽  
Full Scale ◽  
Acid Gases
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