A theoretical study was conducted to investigate the cooling effect of throttling compressed natural gas during the pressure regulation process. The concept of using this effect in cooling down the induction air was investigated. A thermodynamic model was developed for a typical fuel delivery system used on a vehicle fueled with compressed natural gas. The model was based on a set of integral conservation laws applied to each component of the fueling system. Several heat exchanging arrangements between the throttled gas and the inlet air were examined. The effect of the added heat exchanger on engine delivery ratio was examined for different engine sizes as well as for different operating conditions. An increase of 1 to 2.5% in engine delivery ratio was predicted due to the added heat exchanger.

Bird, R. B., Stewart, W. E., and Lightfoot, E. N., 1960, Transport Phenomena, John Wiley & Sons, New York.
Kays, W. M., and Crawford, M. E., 1993, Convective Heat and Mass Transfer, 3rd ed., McGraw-Hill, New York.
Liss, W. E., and Thrasher, W. H., 1991, “Natural Gas as a Stationary Engine and Vehicular Fuel,” SAE 912364, SAE Inc.,
Maxwell, T. T., and Jones, Jesse C., 1994, Alternative Fuel, Emissions, Economics, and Performance, SAE Inc.
Meyer, R., and Meyers, D., Shahed, S. M., and Duggal V. K., 1992, “Development of a heavy duty on-highway natural gas-fueled engine,” SAE 922362.
Mills, A. F., 1995, Heat and mass transfer, Irwin.
Zeleznik, F. J., and Bonnie, J. M., 1985, “Modeling the internal combustion engine,” NASA reference publication 1094.
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