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The penetration of rainwater through the heating ventilation and air conditioning system (HVAC) of a vehicle directly affects the provision of thermal comfort within the vehicle passenger compartment. Present vehicle designs restrict considerably the air-management processes due to reduced space and tighter packaging. The motivation for the study is to get an insight into factors affecting the water ingress phenomenon when a stationary vehicle is subjected to water loading such as heavy rain when parked or waiting in a traffic light or when in a car wash. The test programme made use of a compact closed circuit full-scale automotive climatic wind tunnel that is able to simulate wind, rain and road inclination. The tunnel was developed as part of the collaborative research between the Flow Diagnostics Laboratory (FDL) of the University of Nottingham and Visteon Climate Control Systems [1].

For the past decade or so, automotive entertainment subsystem architectures have consisted of a simple Human Machine Interface (HMI), AM-FM tuner, a tape deck, an amplifier and a set of speakers. Over time, as customer demand for more entertainment features increased, automotive entertainment integrators made room for new features by allowing for the vertical integration of analog audio and adding a digital control. The new digital control came to entertainment subsystems via a low-speed multiplexing scheme embedded into the entertainment subsystem components, allowing remote control of these new features. New features were typically incorporated into the entertainment subsystem by independently packaging functional modules. Examples of these modules are cellular telephone, Compact Disc Jockey (CDJ), rear-seat entertainment, Satellite Digital Audio Radio System (S-DARS) receiver, voice and navigation with its associated display and hardware.

A closed loop full-scale automotive climatic wind tunnel is described. The tunnel simulates wind and rain as well as several road conditions. It generates under controlled heat loading, wind speeds of up to 50kmh with different approach boundary conditions, rains from drizzle to cloudburst and road inclines up to 15° in any direction. The design and optimization process of the tunnel functions is outlined and examples of its use in vehicle development are given. The size constraint and the need for a compact design are important features of the tunnel. The tunnel provides an important test bed for close scrutiny of the relationship between rain ingress, vehicle speed, road condition, heat loading and vehicle geometry. The tunnel can also be used to study vehicle thermal management, vehicle thermal comfort, engine cold starting, and wipers efficiency in sever cold weather.

An accelerated seat durability test was developed to identify potential problems in areas with traditionally high warranty cost and customer dissatisfaction: squeak & rattle and mechanism looseness & efforts. The test inputs include temperature, humidity, road vibration, occupant movements, and mechanism cycling. These inputs were combined into a single 14-day test profile that simulates 10 years and 250,000 km. (approximately 150,000 miles) of 95th percentile customer usage. Various components of the seat assembly are tested together as a system. The test was performed on two current production programs. The test produced issues similar to those found in warranty repair data and evaluations of used seats from high-mileage customer-owned vehicles.

The established method of clearing a misted car windshield or of maintaining a clear view under misting conditions is through the application of an air supply via jet outlets in the instrument panel. The ability of such arrangements to perform adequately is a function of the prevailing environmental conditions, the vehicle speed, the condition of the demist air source and the geometry and arrangement of the jet outlets. This paper presents experimental data obtained in a purpose built environmental chamber designed to accommodate simple rectangular jets impinging on a misted glass surface. The facility consists of three conditioned air sources applied to a test chamber designed to represent the external, internal and demist air flows. Mist conditions on the glass surface are determined using a novel technique employing a CCD camera acquiring grey scale images which are digitally analysed to generate mist detection, grading and clearing contour data.

A low-pressure CO2-based climate-control system has the environmental benefits of CO2 refrigerant but avoids the extremely high pressures of the transcritical CO2 cycle. In the new cycle, a liquid “cofluid” is circulated in tandem with the CO2, with absorption and desorption of CO2 from solution replacing condensation/gas cooling and evaporation of pure CO2. This work compares the theoretical performance of the cycle using two candidate cofluids: N-methyl-2-pyrrolidone and acetone. The optimal coefficient of performance (COP) and refrigeration capacity are discussed in terms of characteristics of the CO2-cofluid mixture. Thermodynamic functions are determined either from an activity coefficient model or using the Soave equation of state, with close agreement between the two approaches. Reductions in COP due to nonideal compressor and heat exchangers are also estimated.

A building-block method, often used for simulating automotive systems, is described in this paper for simulating a driveline system. In the method, a driveline supplier's design responsible components are modeled with explicit FE models. Model accuracy is verified by testing and correlating the components in a free-free condition. Non-design responsible components are modeled using lumped parameters and/or modal models. These components and the validated design responsible components are integrated into a system model and connected using simple lumped parameter connections. Correlation at the system level is performed by making adjustments to the connection parameters and to the parameters of the non-design responsible components. The resulting system model has been used to accurately predict operating responses in a driveline system.

Establishing manufacturing environmental leadership while maintaining overall cost competitiveness is a difficult challenge facing the auto industry. In many cases, environmental initiatives are thought to increase cost and/or restrict manufacturing flexibility. The Commodity Management Supplier Program for Total Waste Management (TWM) implemented globally throughout Ford Motor Company facilities aligns environmental, manufacturing, and corporate citizenship objectives by encouraging supplier-driven continuous process improvement. By creating appropriate TWM contractor waste minimization incentives and utilizing contractor core-business knowledge, the desired effects of reducing total costs while institutionalizing and advancing pollution prevention successes are ultimately realized.