MILLER CYCLE

Prof. Timothy MarbachME258Advanced ThermodynamicsOstap Loredo- ContrerasFall 2012

Miller Cycle Background•The Miller cycle was patented by Ralph Miller, an

American engineer, US patent 2817322 dated Dec 24,

1957.

•The engine may be two stroke or four stroke and may be

run on diesel fuel, gas fuel or dual fuel.

•Mazda is the only known manufacturer that successfully

produced a Miller cycle engine from 1995-2002 on a Mazda

Millenia 2.3lts V6, and currently in Japan 1.3 lts Mazda 2.

•Other Manufactures such as Subaru are nowadays working

on prototype engines(Subaru B5-THP).

Miller Cycle Highlights

•Intake valves closing is delayed and part of the air goes back into the intake manifold.•Expansion ratio is increased without increasing compression ratio by changing the shape of the piston.•Excellent output power and specific power.•Thermal Efficiency improves without risk of knocking, and pumping losses. •Actual compression stroke occurs in the latter 70% to 80% of the compression stroke•NOx reduction.

Miller Cycle

Miller Cycle

Miller Cycle

0–1 is an isobaric process. 1–1 Intake blowback. 1a–2a is an isentropic compression process. 2a–3a is an isochoric heating process. 2a–3a-4a combustion and expansion process.3a-4a Isentropic expansion.4a-1 Constant volume heat rejection1-0 Constant pressure exhaust process

Miller cycle

Miller Cycle

Miller Cycle2.3 Liter V6 Miller Cycle

Engine Size 2255 cc/2.3 L

Horsepower210 hp (157 kW) @ 5300 rpm

Torque210 lb·ft (285 N·m) @ 3500 rpm

20 mpg-US (12 L/100 km;

24 mpg-imp)/28 mpg-US (8.4 L/100 km;

34 mpg-imp)/23 mpg-US (10 L/100 km;

28 mpg-imp)

REFERENCES1.-Dante Giacossa Endothermic Engines (Motori Endotermici), Imprenta Juvenil,S.A. –

Maracaibo,11 -08030 Barcelona, Espaňa.

2.- http://www.mazda.com/mazdaspirit/env/engine/miller.html

3.- Hatamura, K. and Hayakawa, M.: A study of the

improvement effect of Miller-cycle on mean effective

pressure limit for high-pressure supercharged

gasoline engines, JSAE Review 18, 1997.

4.-Sieber. H, Weisser U. Holrler H, and Boulouchos, K; resduction NOX emissions of DI

Diesel Engine by Application of the Miller-System: An Experimental and Numkericla

Investigation. SAE paper No.960844, SAE Special publications, 1996 p.1238-1248.

5.-Fukuzawa Y..Shimoda H, Kahuhama Y., Endo, H, and Tabaka, K, Development of high

Efficiency Miller Cycle Gas Engine, Mitsubishi Heavy Industries, Ltd. Technical Review Vol.

38 No3(Oct. 2001). P146-150

6.- Anderson. M. Assanis D. and Filipi Z., First and Second Alw Analysis of a Naturally-

Aspirated, Miller Cycle, SI engine with late intake Valve Closure, SAE Technical Paper

Series 980889, International Congress and Expositions Detroit Michigan February 23-

26,1998, p.1-16.