Variational Direct Modeling: A Framework Towards Integration of Parametric Modeling and Direct Modeling in CAD

Direct Modeling: Easy Changes in CAD?

Direct Modeling is an emerging CAD technology that uses direct manipulation of the geometry to effect changes in the part model, and is based on a boundary representation database. This paper highlights the differences between Direct Modeling and conventional history-based solid modeling, compares emerging technologies, and discusses what this means for engineering graphics educators. Introduct...

Variational Direct Modeling: How to Keep Design Intent in History-Free CAD

Three-Dimensional Modeling of Combustion Process, Soot and NOx formation In a Direct-injection Diesel Engine

This paper is presented to study the combustion process and emissions in a direct injection diesel engine. Computations are carried out using a three-dimensional model for flows, sprays, combustion and emissions in Diesel engines. Interactions between combustion and emissions with flow field are considered and it is shown that soot mass fraction increases at regions with low turbulence inten...

Functional Modeling in Parametric Cad Systems

We review the transition now being undertaken from 2D drafting to 3D parametric modeling and the development of Building Information Modeling (BIM). We examine the functionality of BIM platforms, using an example from precast concrete structures. We formulate the development of parametric modeling of building systems from the context of SFB modeling and characterize most parametric modeling as ...

Integration of Mechanical CAD and Behavioral Modeling

This article introduces the concept of combining both form (CAD models) and behavior (simulation models) of mechatronic system components into component objects. By composing these component objects, designers automatically create a virtual prototype of the system they are designing. This virtual prototype, in turn, can provide immediate feedback about design decisions by evaluating whether the...