Full-Scale Propulsion Measurements on a Planing Pleasure Yacht in Head Sea

2020 ◽  
Author(s):  
Riccardo Pigazzini ◽  
Fabio De Luca ◽  
Flavio Balsamo ◽  
Amedeo Migali
Keyword(s):  
Mechanical Properties ◽  
Detailed Analysis ◽  
Frequency Domain ◽  
Weather Conditions ◽  
Full Scale ◽  
System Response ◽  
Experimental Setup ◽  
Comprehensive Description ◽  
Quantitative Results ◽  
Shaft Torque

Full scale seakeeping trials are rare, especially planing hull and are in general focused in studying bottom pressures, accelerations and vibrations. In this paper, a comprehensive description of the experimental setup and analysis of full scale seakeeping trials propulsion data of a 65 ft planing pleasure yacht is presented. Torque and rpm have been measured on both propeller shafts during seakeeping trials in mild sea conditions, along with hull motions and accelerations. Correlations between hull motions and propulsion data are discussed, both in the time and frequency domain. Further tests on a shaft sample have been carried out in order to validate its mechanical properties and hence quantitative results regarding shaft torque. The main novelty of the present work lays in a detailed analysis of the propulsion system response of a planing pleasure yacht in mild weather conditions.

Dynamic simulation of a low loaded trickling filter for nitrification

1999 ◽  
Vol 39 (4) ◽  
pp. 163-168 ◽  
Author(s):  
K. Seggelke ◽  
F. Obenaus ◽  
K.-H. Rosenwinkel
Keyword(s):  
Dynamic Simulation ◽  
Weather Conditions ◽  
Full Scale ◽  
Trickling Filter ◽  
Examination Period ◽  
Trickling Filters ◽  
Biofilm Model ◽  
Measuring Campaign

For this report, an existing biofilm model was examined in regard to its suitability for the simulation of full scale trickling filter for nitrification. The system was calibrated using the results ascertained in a measuring campaign under dry weather conditions. The verification was done using the results of a second examination period which included spells of stormwater input. It was possible for all periods to satisfactorily illustrate the degradation performance of the simulated trickling filters in regard to dynamics and quantity.

Theory and full-scale simulation testing of the mechanical properties of anchors under a variable lateral pressure coefficient

2021 ◽  
Vol 14 (2) ◽  
Author(s):  
Tuo Wang ◽  
Jucai Chang ◽  
Zhiqiang Yin ◽  
Peng Gong ◽  
Wenbao Shi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Lateral Pressure ◽  
Pressure Coefficient ◽  
Full Scale ◽  
Lateral Pressure Coefficient ◽  
Simulation Testing

A Comparison of Inverse Models for the Estimation of Ice-Induced Propeller Moments on a Polar Vessel

2021 ◽  
Author(s):  
Brendon M. Nickerson ◽  
Anriëtte Bekker
Keyword(s):  
Rotational Speed ◽  
Continuous Model ◽  
Full Scale ◽  
Lumped Mass ◽  
Mass Model ◽  
Inverse Models ◽  
Lumped Mass Model ◽  
Ill Posed ◽  
Shaft Torque ◽  
Measurement Location

Abstract Full-scale measurements were conducted on the port side propulsion shaft the S.A. Agulhas II during the 2019 SCALE Spring Cruise. The measurements included the shaft torque captured at two separate measurement locations, and the shaft rotational speed at one measurement location. The ice-induced propeller moments are estimated from the full-scale shaft responses using two inverse models. The first is a published discrete lumped mass model that relies on regularization due to the inverse problem being ill-posed. This model is only able to make use of the propulsion shaft torque as inputs. The second model is new and employs modal superposition to represent the propulsion shaft as a combination of continuous modes, resulting in a well-posed problem. This new model requires the additional measurement of the shaft rotational speed for the inverse solution. The continuous model is shown to be more consistent and efficient, which allows its use in real-time monitoring of propeller moments.

Full-Scale Measurements of the Maneuvering Capabilities of Fast Patrol Vessels, Argos Class

2004 ◽  
Vol 41 (01) ◽  
pp. 7-16
Author(s):  
C. Guedes Soares ◽  
R. A. Francisco ◽  
L. Moreira ◽  
M. Laranjinha
Keyword(s):  
Equations Of Motion ◽  
Simulated Data ◽  
Weather Conditions ◽  
Full Scale

Full-scale maneuvering trials of two fast patrol vessels are presented. These trials were aimed at identifying the maneuvering characteristics of the fast patrol vessels of the Argos class. The set of maneuvers chosen were a result of a study based on simulated data, which determined the set of maneuvers that would be most efficient to identifying the parameters of the ship planar equations of motion. These included circles, at different approach speeds and rudder angles, spiral, zigzag, and stopping maneuvers. All maneuvers were performed in good weather conditions. This paper describes and analyzes the results of the full-scale trials of this class of ships.

RESONANCE RISK AND MODE SHAPE MANAGEMENT IN THE FREQUENCY DOMAIN TO PREVENT SQUEAK AND RATTLE

2021 ◽  
pp. 1-30
Author(s):  
Mohsen Bayani ◽  
Casper Wickman ◽  
Aswin Dhananjai Krishnaswamy ◽  
Chidambaram Sathappan ◽  
Rikard Söderberg
Keyword(s):  
Frequency Domain ◽  
Mode Shape ◽  
Autonomous Driving ◽  
System Response ◽  
Shape Similarity ◽  
Passenger Cars ◽  
Baseline Design ◽  
Loop Design ◽  
The Time Domain ◽  
General Connection

Abstract Avoiding quality problems in passenger cars, such as squeak and rattle (S&R), has been a remarkable cost-saving consideration. The introduction of electric engines and less engaged drivers due to autonomous driving is expected to further stress the need for quieter cabins. However, the complexity of the virtual evaluation of S&R events has obstructed the practical treatment of these quality issues in the pre-design-freeze phases of product development. In this study, new quantified frequency-domain metrics are proposed to measure the risk for the generation of S&R in subsystem assemblies. The proposed metrics measure the resonance risk and the mode shape similarity in the critical interfaces for S&R. The calculations are done based on the system response in the frequency domain. Compared to the time-domain evaluation methods, the knowledge about the system excitation levels is not essential and the calculations are more time-efficient. The proposed metrics can be used in closed-loop design optimisation processes to involve S&R attributes in the pre-design-freeze attribute trade-off activities besides other attributes. In this work, these metrics were used in a two-stage optimisation problem to optimise the connection configuration in two industrial cases. As compared to the baseline design, the risk for S&R was reduced by improving the system behaviour in terms of resonance risk and mode shape similarity. This was achieved by applying some adjustments to the location of the fasteners while maintaining the same general connection configuration concept.

Identifying Challenges and Risks Associated with the Analysis of Major Mycotoxins in Feed and Botanicals

2019 ◽  
Vol 102 (6) ◽  
pp. 1689-1694
Author(s):  
Ujwal S. Patil ◽  
Sarah King ◽  
Sean Holleran ◽  
Kristen White ◽  
Cheryl Stephenson ◽  
...  
Keyword(s):  
Sample Preparation ◽  
Weather Conditions ◽  
Herbal Products ◽  
Pros And Cons ◽  
Mycotoxin Analysis ◽  
Quantitative Results ◽  
Traditional Approaches ◽  
The Impact ◽  
Lc Tandem Ms ◽  
Preparation Techniques

Changing weather conditions have heightened the risk of growth of mycotoxigenic molds on crops and various agricultural commodities. Mycotoxins, which are linked to carcinogenic and nephrotoxic effects in animals and humans, have been traditionally analyzed by immunoassays, gas, and LC techniques with spectrophotometric detectors. This review discusses the current techniques and challenges in commercial settings associated with the analysis of mycotoxins in unique matrices such as animal feeds, herbal products, and dietary supplements containing botanicals. Because of the advantages and growing acceptance of LC-tandem MS (MS/MS) over traditional approaches, discussion is mainly based on LC-MS/MS-based approaches. Considering the impact of sample preparation on accuracy of quantitative results, discussion about pros and cons of recently introduced sample preparation techniques is integrated with analytical methods. A section of the review explains the importance and availability of reference materials for mycotoxins. The present discussion provides good insight into the current challenges and developments during mycotoxin analysis of feed and botanicals and addresses the need for researchers in terms of an official MS-based method.

Numerical simulation of ship propulsion transients and full-scale validation

2003 ◽  
Vol 217 (1) ◽  
pp. 41-52 ◽  
Author(s):  
U Campora ◽  
M Figari
Keyword(s):  
Full Scale ◽  
Operating Conditions ◽  
Dynamics Simulation ◽  
Normal Operation ◽  
System Response ◽  
Prime Mover ◽  
Software Environment ◽  
Simulation Code ◽  
Ship Propulsion ◽  
Wide Range

The paper describes a mathematical model for the dynamics simulation of ship propulsion systems. The model, developed in a MATLAB-SIMULINK software environment, is structured in modular form; the various elements of the system are described as individuals blocks (hull, prime mover, gear, waterjet, etc.) and linked together to take their interactions into account. In this way it is possible to characterize the dynamic behaviour of both the single component and the whole propulsion plant. The model may be used to analyse the system response at off-design and transient conditions. In particular, the developed computer simulation code may be considered as a useful tool to facilitate the correct matching of the prime mover (diesel or gas turbine) to the propulsor (waterjet or propeller) in a wide range of operating conditions. The paper shows the application of the methodology to a cruise ferry used to validate the model results through a full-scale test campaign conducted by the authors during normal operation of the ship.

scholarly journals FIRE DYNAMICS IN FAÇADE FIRE TESTS, Measurement, modeling and repeatability

2016 ◽  
Author(s):  
Johan Anderson ◽  
Lars Boström ◽  
Robert Jansson ◽  
Bojan Milovanović
Keyword(s):  
Test Specimen ◽  
Heat Exposure ◽  
Full Scale ◽  
Experimental Setup ◽  
Fire Tests ◽  
Fire Dynamics ◽  
Test Set ◽  
Set Up

Presented is a comparison between full-scale façade tests where SP Fire 105 and BS 8414-1 were used regarding repeatability and the use of modelling to discern changes in the set-ups. Results show that the air movements around the test set-up (the wind) may have a significant impact on the tests and that the heat exposure to the façade surface will among other depend on the thickness of the test specimen. Also demonstrated was that good results could be obtained by modelling of the façade fire tests giving us the opportunity to use these methods to determine the effect of a change in the experimental setup.

Bench to Full-Scale Enhanced Primary Treatment of Municipal Wastewater under Wet Weather Flow for Minimized Pollution Load: Evaluation of Chemical Addition and Process Control Indicators

2020 ◽  
Author(s):  
Mirna Alameddine ◽  
Abdul Rahim Al Umairi ◽  
Mohammed Zakee Shaikh ◽  
Mohamed Gamal El-Din
Keyword(s):  
Process Control ◽  
Municipal Wastewater ◽  
Weather Conditions ◽  
Primary Treatment ◽  
Full Scale ◽  
Operation Conditions ◽  
Wet Weather ◽  
Slow Mixing ◽  
Load Evaluation ◽  
Online Process

The enhanced primary treatment of municipal primary influent under wet weather conditions was studied through a comprehensive approach from bench to full scale. The study delivered a practical solution for managing seasonal fluctuations in the influent wastewater by determining the most effective operation conditions for coagulation/flocculation. Three metal-based coagulants were tested through a series of jar tests. Alum outperformed other coagulants since 1 mg of Al added as alum with low mixing was able to remove 22 NTUs, 19 mg COD and 0.8 mg ortho-P. Three-factor ANOVA indicated that TSS removal depended mostly on rapid mixing while COD and ortho-P removals depended on slow mixing and coagulant dose. In bench and full-scale operations, the addition of polymer did not lead to any pronounced improvements. Finally, turbidity and percent ultraviolet transmittance showed good correlation with TSS and ortho-P which evokes their use as surrogates for micropollutants removal and online process control.

A summary review of mechanical properties prediction methods for textile reinforced polymer composites

2005 ◽  
Vol 219 (2) ◽  
pp. 91-109 ◽  
Author(s):  
J J Crookston ◽  
A C Long ◽  
I A Jones
Keyword(s):  
Mechanical Properties ◽  
Detailed Analysis ◽  
Polymer Composites ◽  
Numerical Models ◽  
Textile Composites ◽  
Prediction Methods ◽  
Reinforced Polymer ◽  
Mechanical Properties Prediction ◽  
The Subject

The use of textile reinforcements for polymer composite components has become a common practice due to the favourable material costs and labour requirements compared with traditional unidirectional prepreg composites, and the high stiffness and strength compared with the use of randomly orientated reinforcements. As a result, determination of both elastic properties and failure behaviour of textile composites has been the subject of substantial research in recent years. This paper presents a review of some of the analytical and numerical models pertaining to the mechanics of textile composites which have been published in the literature. Particular consideration is given to the suitability of models for the analysis of non-orthogonal weave structures such as those which have been deformed in shear during component manufacture. The intention of the paper is not to provide a detailed analysis of the underlying mathematics of the models discussed, but rather to provide an overview of the work conducted in order to direct further reading.

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