Reducing Detail Design and Construction Work Content by Cost-Effective Decisions in Early-Stage Naval Ship Design (original) (raw)

“Design to Cost”-A Viable Concept in Naval Ship Design

Naval Engineers Journal, 1976

The "Design to Cost" concept is investigated from a practical viewpoint by analyzing the impact this design philosophy has had on recent Navy ships. The Guided Missile Frigate design is used as a case study to determine the differences between naval ships "Designed to Cost" and those conventionally designed. The case study includes an investigation of naval architectural features, performance, cost, and an analysis of the design "trade-off" decisions. The analysis of the FFG-7 "Design to Cost" pointed out a number of significant differences compared to conventional ship design. A substantial weight and cost saving was realized due to the highly constrained design environment. It is estimated that the FFG-7 would have "DESIGN TO COST"-A VIABLE CONCEPT IN N A VAL SHIP DESIGN displaced about 1500 tons (40 percent) more if it had not been for the "Design to Cost" procedure. This saving was achieved primarily as a result of a reduction in performance requirements. The future of "Design to Cost" as a viable design philosophy for naval ships is discussed. It is concluded that the Navy must follow this concept in order to hold down the cost of combatant ships but that a decrease in overall ship performance must be expected.

Empirical Cost Estimation for U.S. Navy Ships

Universal Journal of Management, 2019

This article pertains to the development of alternative ship cost modeling methodologies. Most ship cost modeling has been traditionally weight-based. This approach drives the U.S. Navy to select smaller ships that, consequently, require custom-designed shipboard components. This research project is intended to help determine if there is a more accurate way to empirically predict, forecast, and model ship cost. Current and forecasted U.S. Department of Defense budgets require identifying, modeling, and estimating the costs of shipbuilding. Information and data were obtained via publicly available sources and were collected, collated, and used in an integrated risk-based cost and schedule modeling methodology. The objective of this study is to develop a comprehensive cost modeling strategy and approach, and as such, notional data were used. Specifically, we used the Arleigh Burke Class Guided Missile Destroyer DDG 51 Flight I, Flight II, Flight IIA, and Flight III as a basis for the cost and schedule assumptions, but the modeling approach is extensible to any and all other ships within the U.S. Navy. The results will be used to develop recommendations and develop a cost modeling tool on how to implement ship cost forecasts. This example will provide a roadmap for other new ship cost modeling by the U.S. Navy, thereby improving effectiveness and increasing cost savings.

The Impact of Contracts on Ship Design Preparation

Journal of Ship Production and Design, 2012

The implementation of vessel designs is usually achieved through contracts for ship construction or conversion. Accordingly, the design process and the design organization's product have to anticipate and take into account the constraints and requirements of the contracts that control the use of the design, as well as the contract that initiates the design process. This paper addresses the most common contractual factors that have to be considered during preparation of ship designs.

Handling Complexity Aspects in Conceptual Ship Design

scripts.mit.edu

In this paper we present strategies to handle complexity during the conceptual phase of ship design. We introduce the issue by summarizing key ship design advancements during the last six decades, showing the growth in information, which leads to a more complex system. A definition of complexity based on the amount of information necessary to define the system is then discussed, placing the ship as a complex system. A general approach to handle complexity is presented, based on decomposition and encapsulation. Five main aspects of complexity are presented (structural, behavioral, contextual, temporal and perceptual), linking challenges of the conceptual phase to each of the aspects. As case example, techniques to handle the five aspects of an offshore support vessel design are briefly presented. The last section discusses the benefits of the five aspects classification and proposes possible uses and extensions.

The Operator and Engineer-Partners in Naval Ship Design

Naval Engineers Journal, 1973

Today, due to the extreme complexity of modern naval ships, there is a need for the Ship Designer and Ship Operator to work together as partners in designing combatant ships. The ship design process consists of a continual series of "trade off" decisions where one feature is balanced against another. The Ship Designer (PRODUCER) and the Operator (CUSTOMER) must make these decisions together. This paper addresses a number of important design factors which the Engineer and Operator should keep in mind; namely, the meaning and cost of ship performance, the importance of life cycle cost, and the effect of the design spiral. Specific examples are cited explaining the impact that compromises between several performance features can have on a ship design. The message emphasized is that ship performance never comes cheaply and that the Engineer and Operator are in the best positions to make the difficult decisions necessary to produce a balanced ship design.

Influence of Ship Design Complexity on Ship Design Competitiveness

Journal of Ship Production and Design, 2021

Complexity is discussed in design literature mainly through its negative and in some cases positive consequences. This article critically reviews and elaborates the effects of complexity on competitiveness in ship design, its directionality, and magnitude. The article introduces a model for the measurement of ship design complexity and ship design competitiveness based on predefined factors. Archival data of 100 ship design projects from eight different Norwegian designers are used as case study. Multivariate data analysis techniques are employed to study the research model. The results show a significant correlation between complexity and competitiveness in ship design, where the magnitude and directionality of influence vary among different complexity factors. Our findings provide a basis for enhancing complexity management in ship design. Introduction Continual technology improvements and market volatility with its associated uncertainties have a significant impact on and partly ...

ownership cost drivers in ship design and construction

There is a perception that Naval ships cost too much to buy, specify, operate, maintain, sustain and dispose of. The reality or otherwise of this perception can only be determined through a structured cost analysis approach. Through the application of such techniques the stakeholders can begin to understand and address the key issues driving the costs. This paper considers ship design from the perspective of key throughlife, cost-driving subsystems and by designing the ship to minimize the costs associated with these systems. At the simplest level, the ship is there to provide the infrastructure to support these systems. The proposed ship design process wraps the ship around the systems rather than fitting the systems into the hull.

An integrated framework for ship structural optimisation in contract design phase

Analele Universităţii "Dunărea de Jos" din Galaţi. Fascicula XI, Construcţii navale/ Annals of "Dunărea de Jos" of Galati, Fascicle XI, Shipbuilding

This paper demonstrates the implementation of an integrated workflow for the finite element-based structural assessment/optimization of a 3D midship segment of RoPax vessel within the contract design phase. Commercial software such as AVEVA Marine ® , ANSYS ® and modeFRONTIER ® and newly developed in-house tools/modules have been integrated under an automated iterative routine. The structural optimisation carried out with an aim to reduce the structural weight of the ship with least value for vertical centre of gravity. Constraints implemented in the optimization include relevant BV rules and shipyard requirements.The work is performed within the framework of European Union's HOLISHIP (2016-2020) project.

A Mockup Stochastic Program to Study the Impact of Design Uncertainty on ETO Shipbuilding Planning

IFIP Advances in Information and Communication Technology, 2015

A major driver of planning complexity in dynamically changing ETO shipbuilding is design uncertainty far into the design planning and production processes. This leads to uncertainty in task and project completion time, and complex dependencies and correlations driven by the uncertainty in multiple task parameters. The problem is difficult to be solved exactly, and decisionmaking is largely based on experience and gut feeling, with subsequent behavioral challenges. We build a mockup stochastic program to draw attention toand analyze the complexity of formulating and solving the engineering design planning problem. We demonstrate how design uncertainty is affecting the planning complexity and solutions.