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It is an engineering requirement that gases entrained in the coolant flow of an engine must be removed to retain cooling performance, while retaining a volume of gas in the header tank for thermal expansion and pressure control. The main gases present are air from filling the system, exhaust emissions from leakage across the head gasket, and also coolant vapour. These gases reduce the performance of the coolant pump and lower the heat transfer coefficient of the fluid. This is due to the reduction in the mass fraction of liquid coolant and the change in fluid turbulence. The aim of the research work contained within this paper was to analyse an existing phase separator using CFD and physical testing to assist in the design of an efficient phase separator.

This paper describes a hybrid transmission consisting of a Salsbury style rubber belt continuously variable transmission (CVT) and a two-speed manual transmission. Rubber belt CVT transmissions are used extensively in the Mini Baja competitions. Although widely used, rubber belt CVTs have a limited torque ratio range, and teams must reach a balance between top speed and pulling or hill climbing capability. The hybrid transmission described in this paper provides a wider range of torque ratios by combining a CVT with a two-speed manual transmission. Included is a description of the major components, a derivation of the equations used to model the primary pulley in a simulation used to select the desired gear ratios, and a summary of performance characteristics obtained from testing.

Vehicle NVH and crash performance are important attributes related to end use customer comfort and safety. Polyurethane foam systems are currently being used to enhance these performance properties for today's automobiles. Most structural urethane foams used for NVH (stiffness & sealing) and energy management applications utilize low viscosity polyols and polymeric diphenylmethane diisocyanates (PMDI) as starting components. These systems can be difficult for the assembly plants to process due to foam leaking out of the vehicle cavities before it is fully cured. In addition, capital intensive ventilation systems are typically required to safely manage a production line utilizing classical PMDI-based foams. This paper will describe how a new syntactic polyurethane foam, with a paste-like consistency, can enhance vehicle NVH and crashworthiness, while improving processing and safety-related issues.