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Micro-mobility vehicles such as electric scooters and bikes are increasingly used for urban transportation; their designs usually trade off performance and range. Addressing thermal and cooling issues in such vehicles could enhance performance, reliability, life, and range. Limited packaging space within the wheels precludes the use of complex cooling systems that would also increase the cost and complexity of these mass-produced wheel motors. The present study begins by evaluating the external aerodynamics of the scooter to characterise the airflow conditions near the rotating wheel; then, a steady-state conjugate heat transfer model of a commercially available wheel hub motor (500W) is created using commercial computational fluid dynamics (CFD) software, StarCCM+. The CAD model of the motor used for this analysis has an external rotor permanent magnet (PM) brushless DC topology.

The emergence of additive manufacturing (AM) technology has enabled the internal cooling channel layout for high pressure aluminium die casting (HPADC) tools to be designed and modified without topological constraint. Optimisation studies of a full industrial HPADC mould for extending the tool service life has received limited attention due to the high geometrical complexity and the various physics with multi time- and length- scales in addition to the manufacturability limitations. In this work, a new computationally efficient algorithm that employs the adjoint optimisation method has been developed to optimise the coolant channels layout in a complete mould with various 3D printed inserts. The algorithms significantly reduced the computational time and resources by decoupling the fluid flow in the coolant channels from the tool and simulating them separately.

Additive manufacturing (AM) provides significant geometric design freedom for the cooling of high pressure die casting (HPDC) tools. Designing cooling channels that can achieve a uniform temperature throughout the tool-cast interface during the moulding process can limit part warping and sink marks, internal part stresses, and increase tool life. However, the design of the embedded cooling channels requires high computational resources to model the heat transfer process for the cast, mould, and coolant from the moment aluminium is injected into the cavity until the injection for the next cycle. To enable the examination of the effect of various parameters, a simplified 3-D CFD conjugate heat transfer model is introduced by considering the experimental observations. The model decouples the cast part from the mould.

There has been extensive research in the development of Gasoline Direct Injection ‘GDI’ engine exhaust systems with the aim of reducing engine-out emissions and meeting legislation requirements. Depending on the room available for packaging the exhaust system, the engine may be equipped with a single catalyst or two catalysts one close to the engine and another one located further downstream. With the strict particulate matter emission regulations of GDI engine, the engine has to be equipped with a Gasoline Particulate Filter ‘GPF’ in addition to the Closed Coupled Catalyst ‘CCC’. The common practice is to have the GPF further downstream the catalyst. In this paper, an assessment method is carried for a new design of a hot end exhaust system. The new design brings the GPF closer to ‘CCC’ to be packed in the same enclosure. The gas flow velocity and pressure distributions inside the exhaust system are identified using CFD for a uniform exhaust gas flow inlet conditions.

A potentially important, but inadequately studied, source of passengers' exposure to pollutants when a road vehicle is stationary, with an idling engine, results from the ingestion of a vehicle's own exhaust into the passenger compartment through the HVAC intake. We developed and applied a method to determine the fraction of a vehicle's exhaust entering the cabin by this route. Further the influence of three parameters: ambient tail-wind speed, vehicle ground clearance and tail pipe angle, is assessed. The study applies Computational Fluid Dynamic (CFD) simulation to the distribution of exhaust gasses around a vehicle motorized with a 2.2 liter Diesel engine. The simulation employs efficient meshing techniques and realistic loading conditions to develop a general knowledge of the distribution of the gasses in order to inform engineering design.