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In today's competitive market the automotive industry faces many challenges with fuel consumption and emissions leading the list of issues. To be able to achieve the lowest possible fuel consumption and emissions, the industry is targeting the designs of the whole vehicle including power using accessories. This demands the introduction of new technologies. The air conditioning system is no exception and, as such, a new hybrid compressor has been developed. The terms Hybrid Compressor and DSHC are used hereafter. The DSHC has two scroll compression mechanisms, each independently driven--one by the engine drive belt and the other by an electric motor. In this paper, details of the DSHC construction and operating methodology will be discussed and this unique compressor's high efficiency, which contributes to lower fuel consumption and emissions, will be demonstrated.

Noise Vibration Harshness (NVH) is one of the key factors in selecting and designing Automotive A/C systems. This paper will deal with the analysis of pressure pulsation in the suction manifold of a multi-cylinder compressor. Numerical simulation methods have been developed to model and simulate the compression cycle, valve dynamics and mass flow rate into the compressor cylinder. The model was also enhanced to include pressure fluctuations due to the interactions between multiple cylinders in the suction manifold. The analytical results from the simulation program compared favorably with the experimental results. The validation and confirmation of the simulation model was successfully accomplished thus yielding a very valuable tool that could be used during the design stage.

Extensive vehicle fleet testing, followed by laboratory analysis of various vital parts of the air-conditioning systems, have been performed in order to develop a procedure for retrofitting existing CFC-12 automotive air-conditioning systems to HFC-134a. Testing shows that a compressor in good condition that has previously been used with CFC-12, can be re-used with HFC-134a provided that the appropriate oil, desiccant and elastomer is used. Testing has also shown that flushing the system is not necessary. The procedure in this paper was developed as a result of testing and proposes a procedure that will maintain an “acceptable” life of the compressor at a reasonable cost.

A 7-cylinder, wobble plate type, infinitely variable displacement, (IVD), compressor has been developed to meet the following requirements as set forth by the world automotive manufacturers: 1 Wide range of capacity control to eliminate clutch cycling which causes temperature and humidity fluctuations of louver outlet air and unexpected engine load variations 2 Near perfect protection of the evaporator against icing 3 Reliability under all field operating conditions 4 Quiet operation in a compact and lightweight package to suit the new trends in automotive design. A simpler mechanism has been applied to the variable angle cam drive and wobble plate rotation prevention method than with the conventional IVD compressor. The 7-cylinder design, with fewer parts for the piston drive mechanism, enables a quiet compressor of 161.3 cc displacement in a 118 mm diameter casing. An internal control valve is integrated in the center of the valve plate assembly.

This paper presents experimental results that validate eco-driving and eco-heating strategies developed for connected and automated vehicles (CAVs). By exploiting vehicle-to-infrastructure (V2I) communications, traffic signal timing, and queue length estimations, optimized and smoothed speed profiles for the ego-vehicle are generated to reduce energy consumption. Next, the planned eco-trajectories are incorporated into a real-time predictive optimization framework that coordinates the cabin thermal load (in cold weather) with the speed preview, i.e., eco-heating. To enable eco-heating, the engine coolant (as the only heat source for cabin heating) and the cabin air are leveraged as two thermal energy storages. Our eco-heating strategy stores thermal energy in the engine coolant and cabin air while the vehicle is driving at high speeds, and releases the stored energy slowly during the vehicle stops for cabin heating without forcing the engine to idle to provide the heating source.