Effect of Superficial Gas Velocity on the Solid Temperature Distribution in Gas Fluidized Beds with Heat Production
The hydrodynamics and heat transfer of cylindrical gas–solid fluidized beds for polyolefin production was investigated with the two-fluid model (TFM) based on the kinetic theory of granular flow (KTGF). It was found that the fluidized bed becomes more isothermal with increasing superficial gas velocity. This is mainly due to the increase of solids circulation and improvement in gas solid contact. It was also found that the average Nusselt number weakly depends on the gas velocity. The TFM results were qualitatively compared with simulation results of computational fluid dynamics combined with the discrete element model (CFD-DEM). The TFM results were in very good agreement with the CFD-DEM outcomes, so the TFM can be a reliable source for further investigations of fluidized beds especially large lab-scale reactors
Hydrodynamics and heat transfer in gas-solid fluidized beds
In this chapter the extension of an existing two fluid model (TFM) with thermal energy equations is reported. In this model, the particulate phase is treated like a fluid. The implementation as well as the detailed and systematic verification of the extended in-house 3D TFM code using cylindrical coordinates is presented. Following these steps, a careful sensitivity study with respect to time step and grid size was performed as well. This study revealed suitable values for these two parameters to conduct simulations for non-isothermal gas-solid fluidized beds.
Annual review article: Is it time to rethink the gender agenda in entrepreneurship research?
This article develops a critique of contemporary approaches to analysing the impact of gender upon entrepreneurial propensity and activity. Since the 1990s, increasing attention has been afforded to the influence of gender on women’s entrepreneurial behaviour; such analyses have highlighted an embedded masculinity within the entrepreneurial discourse which privileges men as normative entrepreneurial actors. While invaluable in revealing a prevailing masculine bias within entrepreneurship, this critique is bounded by positioning women as a proxy for the gendered subject. This is a potentially limiting analysis that does not fully recognise gender as a human property with myriad articulations enacted throughout entrepreneurial activity. To progress debate, we engage more deeply with the notion of gender as a multiplicity, exploring the implications of such for future studies of entrepreneurial activity.