A new compression ignition (CI) engine concept has been identified which greatly improves power density over conventional CI engines. This paper reviews the scaling laws as they apply to power density (power/crate volume) and derives a parameter reflecting the compactness of any engine design. The new concept is compared to existing engines on the basis of this parameter. Ideal cycle analysis of the multistage thermodynamic processes inherent in the new arrangement leads to the expectation that this engine will be more efficient than current engines. Real cycle simulations and concept design work have confirmed that efficiency can be at least as high as current engines while size is much reduced. Design and analysis are continuing in order to establish that the durability and low emissions will be competitive with modern CI engines.

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