The performance of turbo-generators significantly depends on the design of the power turbine. In addition, the thermoelectric generator can convert waste heat into another source of energy. This research aims to design and optimize an integrated turbo-generator and thermoelectric generator for diesel engines. The goal is to generate electricity from the vehicle exhaust gas. Electrical energy is derived from generators using the flow, pressure, and temperature of exhaust gases from combustion engines and heat-waste. In the case of turbo-generators and thermoelectric generators, the system automatically adjusts the power provided by an inverter. Typically, vehicle exhausts are discarded to the environment. Hence, the proposed conversion to electrical energy will reduce the alternator charging system. This work focuses on design optimization of a turbo-generator and thermoelectric generator for 2500 cc. diesel engines, due to their widespread usage. The concept, however, can also be applied to gasoline engines. Moreover, this model is designed for a hybrid vehicle. Charging during running will save time at the charging station. The optimization by variable van angles of 40°, 50°, 62°, 70°, and 80° shows that the best output power is 62°, which is identical to that calculated. The maximum power outputted from the designed prototype was 1262 watts when operating with an exhaust mass flow rate of 0.1024 kg/s at 3400 rpm (high performance of the engine). This research aims to reduce fuel consumption and reduce pollution from the exhaust, especially for hybrid vehicles.

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Modeling the non-Newtonian flow of polymer melts in single-screw extrusion generally requires numerical methods. This study analyzes the viscous dissipation of the melt-conveying zone, which is mainly responsible for the axial melt temperature increase, in single-screw extruders for both one-and two-dimensional stationary, fully developed flows of a power-law fluid. Rewriting the flow equations and applying the theory of similarity revealed three independent parameters that influence the physics of the fluid flow: the dimensionless pressure gradient P p;z , the power-law exponent n, and the screw-pitch ratio t=D b. Based on these parameters, we carried out a comprehensive numerical parametric study evaluating viscous dissi-pation and flow rate. Here, we present four heuristic models that predict the viscous dissipation of a power-law fluid in the melt-conveying zone of single-screw extruders. For one-dimensional and two-dimensional flows, we developed models for both a given pressure gradient and a given throughput. The approximation equations obtained allow fast and stable prediction without the need for numerical simulations of viscous dissipation. The accuracy of the heuristic models developed was validated in an error analysis, which showed that our approaches provide excellent approximations of the numerical results.

Abstract. Microturbines are small gas turbines that have the capacity range of 25-300 kW. The main components of microturbine are compressor, turbine, combustor and recuperator. This research paper focuses on the design of radial inflow turbine that operates in 30 kW microturbine. In order to operate the 30 kW microturbine with the back work ratio of 0.5, the radial inflow turbine should be designed to produce power at 60 kW. With the help of theory of turbomachinery and the analytical methods, the design parameters are derived. The design results are constructed in 3D geometry. The 3D fluid-geometry is validated by computational fluid dynamics (CFD) simulation. The simulation results show the airflow path, the temperature distribution, the pressure distribution and Mach number. According to the simulation results, there is no flow blockage between vanes and no shock flow occurs in the designed turbine.

Latex-dipping process in a medical-gloves production line is one of the most critical components that affect the final product quality. In this process, glove-shaped formers are moved through an open-channel latex-dipping tank. Since the gloves have long arms and the latex compound is opaque, it is difficult or impossible to directly observe the flow beneath the free surface. On the other hand, the surface wave and vortex shedding patterns are easily observed or measured on-site. Therefore, it will be beneficial to identify and establish a relationship between the observable surface quantities and the flow underneath. In this work, Computational Fluid Dynamics (CFD) is used to simulate a free-surface flow past a glove-shaped former in comparison to that over a vertical cylinder of the same diameter. The computational results showed that the vortex generation in the near wake is inhibited by the effect of the free surface, and reducing the vortex shedding and vorticity. The shedding from the fingertips has little to no effect on the surface. Most surprisingly, the free surface flow past a glove-shaped former in this setting does not exhibit a transient vortex-shedding pattern unlike the case with a vertical cylinder. This disparity among others makes a vertical cylinder a poor simplified surrogate model for the glove-shaped former.