Engineering Commons^™

Modeling Of Thermal Non-Equilibrium In Superheated Injector Flows, Shivasubramanian Gopalakrishnan

Open Access Dissertations

Among the many factors that effect the atomization of a fuel spray in a com- bustion chamber, the flow characteristics of the fuel inside the injector nozzle play significant roles. The enthalpy of the entering fuel can be elevated such that it is higher than the local or downstream saturation enthalpy, which will result in the flash-boiling of the liquid. The phase change process dramatically effects the flow rate and has the potential to cause subsonic two-phase choking. The timescale over which this occurs is comparable to the flow-through time of the nozzle and hence any attempt to model this …

A Comprehensive Study Of The Extensional Rheology Of Complex Fluids, Manojkumar Chellamuthu

Doctoral Dissertations 1896 - February 2014

Non-Newtonian fluids play an important role in our daily life. The visco-elastic nature of these fluids comprises a class of materials found in variety of items ranging from food, to plastic products, to the cosmetic products. The design and tunability of non-Newtonian fluids is only possible through an understanding of their complex dynamics and rheology. In this thesis, a filament stretching rheometer is used to investigate the extensional rheology of three important classes of complex visco-elastic fluids namely surfactants, suspensions and polymers.

Surfactants with their unique molecular amphiphilic chemistry allow them to form long wormlike micellar structures, which behave like …