David John Benson

Supergranulation Scale Convection Simulations

Results of realistic simulations of solar surface convection on the scale of supergranules (96 Mm wide by 20 Mm deep) are presented. The simulations cover only 10% of the geometric depth of the solar convection zone, but half its pressure scale heights. They include the hydrogen, first and most of the second helium ionization zones. The horizontal velocity spectrum is a power law and the horizontal size of the dominant convective cells increases with increasing depth. Convection is driven by buoyancy work which is largest close to the surface, but significant over the entire domain. Close to the surface buoyancy driving is balanced by the divergence of the kinetic energy flux, but deeper down it is balanced by dissipation. The damping length of the turbulent kinetic energy is 4 pressure scale heights. The mass mixing length is 1.8 scale heights. Two thirds of the area is upflowing fluid except very close to the surface. The internal (ionization) energy flux is the largest contributor to the convective flu...

Work in progress — Transforming entrepreneurship and innovation instruction in Fluid Mechanics

Case studies, a valuable tool in business education, are used to permit students access to situations and environments which are not accessible in a classroom. One element of a business case study differentiating it from a simple company history is that the tone and content is often designed with an ulterior objective or to achieve a certain state of mind before a discussion point: they are engineered learning environments. Within an engineering classroom, the business case study approach can be manipulated to introduce students to concepts of entrepreneurship and innovation and to facilitate an understanding of how classroom content can be employed in practice. A series of limited-scope case studies have been introduced in a junior-level Fluid Mechanics class which align entrepreneurship and innovation objectives with course content by introducing subject-specific analysis, sample application and reflection to the case studies. Two elements of a three-activity sequence are presented beginning with an introduction to entrepreneurship and the “painstorming” concept through a case study of a foam-reducing keg tap. The concept of social entrepreneurship is then introduced using a system implemented by a South African social entrepreneur to provide drinking water for rural communities using playground equipment as a pump.

Work in progress — Product evolution from an engineering perspective

In entrepreneurship and innovation circles, “painstorming” is a process by which a person examines either a particular product or the world around them with the goal of identifying negative customer/user issues to serve as focal points for development efforts or research. In business education, the concept of product evolution is used to both chart the stages in the product development and to examine changes in a product over time from a product characteristics and market-needs perspective. To promote the transfer of classroom knowledge into practice through the context of entrepreneurship, a classroom tool termed a “product evolution study” has been developed to help students identify and describe the growth and transformation of a product within the context of the energy relations, material properties and engineering involved in the products as they relate to class learning objectives. This tool is intended for insertion within a content-oriented engineering class, such as Fluid Mechanics, to provide context for the subject matter and to model the everyday application of entrepreneurial thinking. Student experiences with this type of analysis are being used to develop a formal, graphical procedure for describing the evolution of a product from the standpoint of the underlying physics involved in the products development.