{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T03:36:07Z","timestamp":1773200167294,"version":"3.50.1"},"reference-count":26,"publisher":"SAE International","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["SAE Int. J. Engines"],"abstract":"<div class=\"section abstract\"><div class=\"htmlview paragraph\">This paper describes predictive models and validation experiments used to quantify the in-chamber heat transfer of LiquidPiston\u2019s rotary 70cc SI \u201cXMv3\u201d engine.<\/div><div class=\"htmlview paragraph\">The XMv3 engine is air cooled, with separate cooling flow paths for the stationary parts and the rotor. The heat transfer rate to the stationary parts was measured by thermal energy balance of that circuit\u2019s cooling air. However, because the rotor\u2019s cooling air mixes internally with the engine\u2019s exhaust gas, a similar procedure was not practical for the rotor circuit. Instead, a CONVERGE CFD model was developed, and used together with GT-POWER to derive boundary conditions to estimate a ratio between rotor and stationary parts heat transfer, thus allowing estimation of rotor and total heat losses.<\/div><div class=\"htmlview paragraph\">For both cases studied (5000 and 9000 rpm under full load), the rotor\u2019s heat loss was found to be \u223c60% that of the stationary parts, and overall heat losses were less than 35% of supplied fuel energy.<\/div><div class=\"htmlview paragraph\">The significance of this work relates to the following facts:\n<ul class=\"list disc\"><li class=\"list-item\"><div class=\"htmlview paragraph\">It represents the first time that heat transfer was quantified for the \u201cX\u201d engine architecture;<\/div><\/li><li class=\"list-item\"><div class=\"htmlview paragraph\">Preliminary experimental and modelling results show reasonable correlation<\/div><\/li><li class=\"list-item\"><div class=\"htmlview paragraph\">The predictive models developed will inform future engine cooling system optimization work, leading to higher power densities and thermal efficiencies. Results for these two metrics are already market competitive in the 3 horsepower engine size.<\/div><\/li><\/ul><\/div><\/div><\/jats:p>","DOI":"10.4271\/2016-32-0033","type":"journal-article","created":{"date-parts":[[2016,11,8]],"date-time":"2016-11-08T00:07:42Z","timestamp":1478563662000},"page":"2368-2380","source":"Crossref","is-referenced-by-count":44,"title":["Measurement and Prediction of Heat Transfer Losses on the XMv3 Rotary Engine"],"prefix":"10.4271","volume":"09","author":[{"given":"Tiago J.","family":"Costa","sequence":"first","affiliation":[{"name":"Universidade do Minho"}]},{"given":"Mark","family":"Nickerson","sequence":"additional","affiliation":[{"name":"LiquidPiston Inc"}]},{"given":"Daniele","family":"Littera","sequence":"additional","affiliation":[{"name":"LiquidPiston Inc"}]},{"given":"Jorge","family":"Martins","sequence":"additional","affiliation":[{"name":"Universidade do Minho"}]},{"given":"Alexander","family":"Shkolnik","sequence":"additional","affiliation":[{"name":"LiquidPiston Inc"}]},{"given":"Nikolay","family":"Shkolnik","sequence":"additional","affiliation":[{"name":"LiquidPiston Inc"}]},{"given":"Francisco","family":"Brito","sequence":"additional","affiliation":[{"name":"Universidade do Minho"}]}],"member":"2796","published-online":{"date-parts":[[2016,11,8]]},"reference":[{"key":"ref0","doi-asserted-by":"crossref","unstructured":"Sprague S. B. , Park S. , Walther D. C. , Pisano A. P. , and Fernandez-pello A. C. Development and characterisation of small-scale rotary engines Int. J. Altern. Propuls. 1 2\/3 275 293 2007","DOI":"10.1504\/IJAP.2007.013016"},{"key":"ref1","doi-asserted-by":"crossref","unstructured":"Froede , W. The NSU-Wankel Rotating Combustion Engine SAE Technical Paper 610017 1961 10.4271\/610017","DOI":"10.4271\/610017"},{"key":"ref2","doi-asserted-by":"crossref","unstructured":"Shkolnik A. and Shkolnik N. High Efficiency Hybrid Cycle (HEHC) Thermodynamic Cycle US Patent 8,365,698 2007","DOI":"10.4271\/2008-01-2448"},{"key":"ref3","doi-asserted-by":"crossref","unstructured":"Ribeiro , B. and Martins , J. Direct Comparison of an Engine Working under Otto, Miller and Diesel Cycles: Thermodynamic Analysis and Real Engine Performance SAE Technical Paper 2007-01-0261 2007 10.4271\/2007-01-0261","DOI":"10.4271\/2007-01-0261"},{"key":"ref4","doi-asserted-by":"crossref","unstructured":"Martins , J. , Uzuneanu , K. , Ribeiro , B. , and Jasasky , O. Thermodynamic Analysis of an Over-Expanded Engine SAE Technical Paper 2004-01-0617 2004 10.4271\/2004-01-0617","DOI":"10.4271\/2004-01-0617"},{"key":"ref5","unstructured":"Torregrosa J. , Olmeda P. C. , and Romero C. A. Revising Engine Heat Transfer J. Eng. Ann. Fac. Eng. Hunedoara 3 245 265 2008"},{"key":"ref6","doi-asserted-by":"crossref","unstructured":"Woschni , G. A Universally Applicable Equation for the Instantaneous Heat Transfer Coefficient in the Internal Combustion Engine SAE Technical Paper 670931 1967 10.4271\/670931","DOI":"10.4271\/670931"},{"key":"ref7","doi-asserted-by":"crossref","unstructured":"Gorla R. and Bartrand T. Couette flow heat loss model for the rotary combustion engine Proc. Inst. Mech. Eng. 6 210 587 1996","DOI":"10.1243\/PIME_PROC_1996_210_233_02"},{"key":"ref8","doi-asserted-by":"crossref","unstructured":"Rakopoulos C. , Kosmadakis G. , and Pariotis E. Critical evaluation of current heat transfer models used in CFD in-cylinder engine simulations and establishment of a comprehensive wall-function formulation Appl. Energy 87 5 1612 1630 2010","DOI":"10.1016\/j.apenergy.2009.09.029"},{"key":"ref9","doi-asserted-by":"crossref","unstructured":"HAN Z. and Reitz R. A Temperature Wall Function Formulation for Variable-density Turbulent Flows with Application to Engine Convective Heat Transfer Modeling Int. J. Heat Mass Transf. 40 3 613 625 1997","DOI":"10.1016\/0017-9310(96)00117-2"},{"key":"ref10","doi-asserted-by":"crossref","unstructured":"Wimmer , A. , Pivec , R. , and Sams , T. Heat Transfer to the Combustion Chamber and Port Walls of IC Engines -Measurement and Prediction SAE Technical Paper 2000-01-0568 2000 10.4271\/2000-01-0568","DOI":"10.4271\/2000-01-0568"},{"key":"ref11","unstructured":"Ebrahimi K. M. , Lewalski A. , Pezouvanis A. , and Mason B. Piston Data Telemetry in Internal Combustion Engines Am. J. Sens. Technol. 2 1 7 12 2014"},{"key":"ref12","unstructured":"Badgley P. , Kamo R. , and Doup D. Adiabatic Wankel Type Rotary Engine 1988"},{"key":"ref13","unstructured":"Heywood J. Internal Combustion Engine Fundamentals McGraw-Hill, Inc. 1988"},{"key":"ref14","doi-asserted-by":"crossref","unstructured":"Meng P. , Rice W. , Schock H. , and Pringle D. Preliminary Results on Performance Testing of a Turbocharged Rotary Combustion Engine 1982","DOI":"10.4271\/820354"},{"key":"ref15","doi-asserted-by":"crossref","unstructured":"Shkolnik , A. , Littera , D. , Nickerson , M. , Shkolnik , N. et al. Development of a Small Rotary SI\/CI Combustion Engine SAE Technical Paper 2014-32-0104 2014 10.4271\/2014-32-0104","DOI":"10.4271\/2014-32-0104"},{"key":"ref16","doi-asserted-by":"crossref","unstructured":"Littera D. , Nickerson M. , Kopache A. , Machamada G. , Sun C. , Schramm A. , Medeiros N. , Becker K. , Shkolnik S. , and Shkolnik A. Development of the XMv3 High Efficiency Cycloidal Engine SAE Technical Paper 2015-32-0719 2015","DOI":"10.4271\/2015-32-0719"},{"key":"ref17","unstructured":"Munson B. , YOUNG D. , OKIISHI T. , and HUEBSCH W. Fundamentals of Fluid Mechanics Sixth Don Fowley 2009"},{"key":"ref18","unstructured":"Science C. Converge CFD software https:\/\/convergecfd.com\/ 19 Jan 2016"},{"key":"ref19","doi-asserted-by":"crossref","unstructured":"Amsden A. KIVA-3V: A Block Structured KIVA Program for Engines with Vertical or Canted Valves 1997","DOI":"10.2172\/505339"},{"key":"ref20","doi-asserted-by":"crossref","unstructured":"Angelberger , C. , Poinsot , T. , and Delhay , B. Improving Near-Wall Combustion and Wall Heat Transfer Modeling in SI Engine Computations SAE Technical Paper 972881 1997 10.4271\/972881","DOI":"10.4271\/972881"},{"key":"ref21","unstructured":"Park H. J. DEVELOPMENT OF AN IN-CYLINDER HEAT TRANSFER MODEL WITH VARIABLE DENSITY EFFECTS ON THERMAL BOUNDARY LAYERS The university of the Michigan 2009"},{"key":"ref22","doi-asserted-by":"crossref","unstructured":"Nijeweme D. , Kok J. , Stone C. , and Wyszynski L. Unsteady in-cylinder heat transfer in a spark ignition engine : experiments and modelling Proc. Inst. Mech. Eng. Part D J. Automob. Eng. 215 2001","DOI":"10.1243\/0954407011528329"},{"key":"ref23","unstructured":"C. S. Inc. CONVERGE 2.2 Theory Manual 2015"},{"key":"ref24","doi-asserted-by":"crossref","unstructured":"Scarcelli , R. , Richards , K. , Pomraning , E. , Senecal , P. et al. Cycle-to-Cycle Variations in Multi-Cycle Engine RANS Simulations SAE Technical Paper 2016-01-0593 2016 10.4271\/2016-01-0593","DOI":"10.4271\/2016-01-0593"},{"key":"ref25","unstructured":"Fahl H. The validation of the explosive fumes dynamics in rooms New Trends Res. Energ. Mater. 124 134 2009"}],"container-title":["SAE International Journal of Engines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/saemobilus.sae.org\/downloads\/articles\/2016-32-0033\/Full%20Text%20PDF","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T15:22:37Z","timestamp":1760109757000},"score":1,"resource":{"primary":{"URL":"https:\/\/saemobilus.sae.org\/articles\/measurement-prediction-heat-transfer-losses-xmv3-rotary-engine-2016-32-0033"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,11,8]]},"references-count":26,"journal-issue":{"issue":"4"},"URL":"https:\/\/doi.org\/10.4271\/2016-32-0033","relation":{},"ISSN":["1946-3936","1946-3944"],"issn-type":[{"value":"1946-3936","type":"print"},{"value":"1946-3944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,11,8]]},"article-number":"2016-32-0033"}}