scholarly journals Modeling of full-scale propeller characteristics at the life cycle initial stages of marine systems

2021 ◽  
Vol 1864 (1) ◽  
pp. 012150
Author(s):  
Aleksey Yu. Yakovlev ◽  
Thant Zin
Keyword(s):  
Data in Brief ◽  
2020 ◽  
Vol 33 ◽  
pp. 106487
Author(s):  
Jorge Senán-Salinas ◽  
Junkal Landaburu-Aguirre ◽  
Alberto Blanco ◽  
Raquel García-Pacheco ◽  
Eloy García-Calvo

2011 ◽  
Vol 63 (1) ◽  
pp. 164-170 ◽  
Author(s):  
K. De Gussem ◽  
T. Wambecq ◽  
J. Roels ◽  
A. Fenu ◽  
G. De Gueldre ◽  
...  

An ASM2da model of the full-scale waste water plant of Bree (Belgium) has been made. It showed very good correlation with reference operational data. This basic model has been extended to include an accurate calculation of environmental footprint and operational costs (energy consumption, dosing of chemicals and sludge treatment). Two optimisation strategies were compared: lowest cost meeting the effluent consent versus lowest environmental footprint. Six optimisation scenarios have been studied, namely (i) implementation of an online control system based on ammonium and nitrate sensors, (ii) implementation of a control on MLSS concentration, (iii) evaluation of internal recirculation flow, (iv) oxygen set point, (v) installation of mixing in the aeration tank, and (vi) evaluation of nitrate setpoint for post denitrification. Both an environmental impact or Life Cycle Assessment (LCA) based approach for optimisation are able to significantly lower the cost and environmental footprint. However, the LCA approach has some advantages over cost minimisation of an existing full-scale plant. LCA tends to chose control settings that are more logic: it results in a safer operation of the plant with less risks regarding the consents. It results in a better effluent at a slightly increased cost.


2017 ◽  
Vol 25 (3) ◽  
pp. 2552-2569 ◽  
Author(s):  
Anju Singh ◽  
Sheetal Jaisingh Kamble ◽  
Megha Sawant ◽  
Yogita Chakravarthy ◽  
Absar Kazmi ◽  
...  

1993 ◽  
Author(s):  
T. L. Gaudette ◽  
Larry Fraser ◽  
S. A. Della Villa

Product reliability is influenced by both design and operating and maintenance practices. This means both the equipment manufacturer and the equipment’s operator have an impact on the systems’ achievable level of availability. Many variables such as application (utility or cogeneration) or service or duty cycle (peaking, cycling, or continuous duty), influence the expected availability/reliability of any unit. These variables and an understanding of the expected “economic demand” the unit must fill are important elements for a realistic and accurate reliability assessment. These variables also affect the expected maintenance costs associated with the unit. Both the equipment manufacturer and the equipment operator have a vested interest in understanding and influencing this process. If the expected level of reliability/availability is a major requirement of the equipment owner/operator, then there must be an accurate understanding of how the reliability of the unit will be protected over the long term. Thus the unit first cost and life cycle cost can be estimated in a meaningful way. The objective of this paper is to provide an assessment of proved design reliability along with the application of on condition maintenance of Turbo Power and Marine Systems’ (Turbo Power) most recent product introduction, the FT8. A computer-aided reliability analysis was made by Turbo Power with the support of Strategic Power Systems, Inc. (SPS), to demonstrate and support the suitability of the FT8 for both peaking and continuous duty applications utilizing on condition maintenance concepts. Consequently, the presentation of the RAM analysis is organized to assist in developing a complete and comprehensive understanding of the evolution of the product and to develop realistic RAM (Reliability, Availability, and Maintainability) and life cycle cost expectations.


Author(s):  
Thaís Andrade de Sampaio Lopes ◽  
Luciano Matos Queiroz ◽  
Asher Kiperstok

Life Cycle Assessment (LCA) was applied to estimate and analyze the environmental impacts from the construction and operation phases of a full-scale wastewater treatment plant (WWTP) located in the municipality of Lauro de Freitas, Bahia, Brazil. The WWTP process consists of the association of an Upflow Anaerobic Sludge Blanket (UASB) reactor followed by four constructed wetlands (CWL) and a disinfection step. The functional unit was defined as one cubic meter of treated effluent during the useful life of this WWTP (20 years). The LCA was carried out using SimaPro® software and the Centre of Environmental Science (CML) assessment method. The environmental impacts during construction phase were mainly from the wooden forms for concrete and the use of reinforcing steel. During the operation phase, the chlorine used as effluent disinfectant caused the greatest impacts in the abiotic depletion and acidification categories. Macronutrient concentrations present in the treated effluent and the methane generated also caused significant environmental impacts during the WWTP’s useful life. The results obtained highlight the importance of the application of a methodology like LCA to assist in decision-making with regard to the implementation, construction and operation of a WWTP.


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