ABSTRACT Thrust & Torque Calculations for MOV’s using Microsoft Office Products Prepared by Michael C. Richard Teledyne Brown Engineering Desktop computing using Microsoft Office products have changed the way that engineering calculations are performed. But, is the change for the better or the worse? Engineering Managers are faced with the task of “computerizing” engineering calculations all the time. This paper presents some guidance on how to choose the method that best suits your calculation needs. Specifically, three methods of calculating thrust and torque for MOV’s will be presented. The three methods consist of an Excel model, an Access model, and a final model which uses Microsoft Visual Basic combined with Access (Microsoft Jet) and Excel. Pro’s and con’s will be presented for each method. Finally, the subject of software validation and verification will be presented with discussions on how this subject applies to the four methods of calculation presented above. The information presented in this paper should provide the Engineering Managers, as well as the engineers responsible for “computerizing” the calculations with the tools they need to make a successful decision.
Engineering calculations have changed significantly over the last ten years. With the emergence of desktop PC's, many different software products have been developed to assist engineers with calculations. In particular, Microsoft has developed a family of "desktop" software products named Office 97 to assist with the many facets of business calculations. Software products, like Office, allow engineers to develop and program their own calculations, instead of relying solely on software engineers who may not have a background in the field of interest. This calculation evolution has on one hand empowered the engineer, but on the other hand has added requirements for new skills. If you were going to develop an engineering calculation or you were going to manage the development of an engineering calculation, where would you start? Microsoft, like many other software developers provide multiple tools to accomplish the same task. Even if you do select a particular tool, there are a seemingly infinite number of ways to approach the engineering calculation. Given this situation, which approach should you choose? Remember, as a developer or a manager, you have a finite budget and a finite time table. To make these decisions, you need a software development model.
1998 MUG Conference
Page 1 of 8
Thrust & Torque Calculations for MOV’s using Microsoft Products
Software Development Model
There are many models available for developing software as presented in References . One of the simplest models is defined as the Waterfall model and is illustrated as follows:
Requirements Analysis Requirements Definitions Design Coding Testing Reviews & Inspections
For commercial grade software, the phases of the Waterfall model are summarized as follows: • Requirements Analysis: Concept based on market research usually stated in the customers terminology (i.e. The software must provide a live screen of thrust vs time during testing). • Requirements Definition: Marketing concept restated in the software developers terminology (i.e. The software must provide a strip chart control for viewing specific channel data during testing which updates at a rate of 500 samples/second) • Design: Define system architecture necessary to meet the requirements (for example Operating System: Windows NT/98/95/3.11,DOS 6.22 Main Development Tools: C/C++/Visual Basic/Access/Excel/Word/… Third Party Development Tools: ActiveX Controls,… Additional Hardware: Data Acquisition Boards,… • Coding: Write code to implement the Design phase. • Testing: Even though the Waterfall model illustrates that testing begins after the coding has been completed, in reality, verification tests are developed and implemented during...
Please join StudyMode to read the full document