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A flow network method was developed to predict the underhood temperature distribution of an automobile. The method involves the solution of simplified energy and momentum equations of the air flow in control volumes defined by subdividing the air space between the surfaces of the underhood components and the front-end geometry. The control volumes are interconnected by ducts with branches and bends to form a flow network. Conservation of mass and momentum with appropriate pressure-loss coefficients leads to a system of algebraic equations to be solved for the flow rates through each volume. The computed flow rates are transferred to a thermal model to calculate the temperatures of the air and the major vehicle components that affect the underhood environment. The method was applied to a 1986 3.0L Taurus and compared with vehicle experiments conducted in a windtunnel.

The 1979 decision by the Brazilian government to confirm their plans for widespread distribution of neat ethanol fuel (100%) to reduce petroleum imports prompted many investigations of the effect of the ethanol on passenger car durability. This paper describes results of a program to develop crankcase lubricants suitable for service with ethanol fuel over a wide temperature range. Engine wear at low temperatures was found to be the major problem. A low temperature Sequence V-D (PV-1) test previously developed, provided a suitable environment for lubricant evaluation. Service station oils at the API SE and SF quality levels were developed based on consideration of their wear and corrosion inhibition when emulsified with ethanol. They were found to reduce critical wear parameters in the low temperature V-D test.