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Title: Continuously Variable Displacement Engine Concept Validation

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  1. Engine Systems Innovation, Inc., Rancho Palos Verdes, CA (United States)
Publication Date:
Research Org.:
Engine Systems Innovation, Inc., Rancho Palos Verdes, CA (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
OSTI Identifier:
Report Number(s):
DOE Contract Number:
Type / Phase:
Resource Type:
Technical Report
Country of Publication:
United States
33 ADVANCED PROPULSION SYSTEMS; Variable stroke engine; continuously variable displacement engine; variable z-crank engine

Citation Formats

Arnold, Steve. Continuously Variable Displacement Engine Concept Validation. United States: N. p., 2017. Web.
Arnold, Steve. Continuously Variable Displacement Engine Concept Validation. United States.
Arnold, Steve. Wed . "Continuously Variable Displacement Engine Concept Validation". United States. doi:.
title = {Continuously Variable Displacement Engine Concept Validation},
author = {Arnold, Steve},
abstractNote = {},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2017},
month = {Wed Mar 01 00:00:00 EST 2017}

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  • The project began under a corporative agreement between Mack Trucks, Inc and the Department of Energy starting from September 1, 2005. The major objective of the four year project is to demonstrate a 10% efficiency gain by operating a Volvo 13 Litre heavy-duty diesel engine at a constant or narrow speed and coupled to a continuously variable transmission. The simulation work on the Constant Speed Engine started on October 1st. The initial simulations are aimed to give a basic engine model for the VTEC vehicle simulations. Compressor and turbine maps are based upon existing maps and/or qualified, realistic estimations. Themore » reference engine is a MD 13 US07 475 Hp. Phase I was completed in May 2006 which determined that an increase in fuel efficiency for the engine of 10.5% over the OICA cycle, and 8.2% over a road cycle was possible. The net increase in fuel efficiency would be 5% when coupled to a CVT and operated over simulated highway conditions. In Phase II an economic analysis was performed on the engine with turbocompound (TC) and a Continuously Variable Transmission (CVT). The system was analyzed to determine the payback time needed for the added cost of the TC and CVT system. The analysis was performed by considering two different production scenarios of 10,000 and 60,000 units annually. The cost estimate includes the turbocharger, the turbocompound unit, the interstage duct diffuser and installation details, the modifications necessary on the engine and the CVT. Even with the cheapest fuel and the lowest improvement, the pay back time is only slightly more than 12 months. A gear train is necessary between the engine crankshaft and turbocompound unit. This is considered to be relatively straight forward with no design problems.« less
  • The data measurement and reduction system for the Pouliot variable displacement engine uses a Hewlett Packard 2114A minicomputer. The raw data are processed to compute the horsepower, air-fuel ratio, equivalence ratio, brake specific fuel consumption, and brake specific emissions of unburned hydrocarbons, oxides of nitrogen, and carbon monoxide. Emissions are checked for consistency by applying the chemical equilibrium theory of Spindt.
  • A five-cylinder variable displacement research engine was designed, built, and tested. Displacement is varied by changing the piston stroke using a four-bar linkage. Before the engine was built, its dynamics were thoroughly analyzed, and a five-cylinder configuration was selected to minimize vibration. Test data show that BSFC is, as expected, less dependent on load than in conventional engines, and averages less than 0.5 lb/bhp-hr over the load and speed range of ordinary automobile operation. The impact of exhaust gas recirculation on emissions levels was studied experimentally. Several methods for estimating urban fuel economy from dynamometer data predict a 20 tomore » 25% improvement compared with conventional engines at the same emissions levels.« less
  • The piston and the three connecting links in the Pouliot Variable Displacement Engine are dynamically analyzed. Given the cylinder pressure as a function of the crank angle, the internal member and bearing loads are determined, as well as the unbalanced forces due to the reciprocating masses. Friction forces which result in approximate power losses are included. The unbalanced forces are closely examined, and it is shown that a five-cylinder in-line design is the best choice for the prototype engine to be built at Sandia Laboratories, Livermore.