LIFPIV I J I J AD AM C mol/ F(T) K() T Vpt Vp / Voc / Vo B / Cp B D Fi Fg fp fr l m ne Pa Pfm Px Top

Pr R Rf Rp Rr r T2 T3 V Vs W Wp Wr a / 3 o / 3 p i r/ o

2-1 2-2 2-2-1 2-2-2 2-2-3 2-2-4 2-2-5 2-3 2-3-1 2-3-2 2-3-3 2-4

3 PIV 3-1 3-2 PIV 3-2-1 PIV() 3-2-2 PIV 3-2-2-1 PIV 3-2-2-2 3-3 3-3-1 3-3-2 3-4 3-4-1 PIV 3-4-2 PIV 3-5 LIFPIV 4-1 4-2 4-2-1 4-2-2 4-2-3 4-2-4 4-3 4-3-1 EJ22 922 4-3-2 4-3-3 4-4 LIFPIV 4-4-1 4-4-2 4-4-3 4-4-4

4-5 LIF, PIV 4-5-1 4-5-2 4-5-3 4-5-4 4-6 8 5-1 5-2 5-2-1 5-2-2 5-2-2-1 5-2-2-2 5-2-3 5-2-4 5-2-4-1 5-2-4-2 5-3 5-3-1 5-3-2 5-3-3 5-3-4 5-3-4-1 3 5-3-4-2 2 NSR 5-3-5 5-3-5-1 3 5-3-5-2 2 5-3-5-3 NSRNarrow Single Ring2 5-4 5-4-1 5-4-2 2

6-1 LIF 6-2 PIV 6-3 LIF PIV

1-2 1-2-1LIF Fig.1-1 Schematic view of Laser induced fluorescence method 2

Fig.1-2(a)(b) Method of calibration Fig.1-3 Influence of concentration on fluorescence ( ) 4

Fig.1-4 Influence of oil film temperature on the Fluorescence intensity ( ) 5

Fig.1-5 Oil film thickness adjacent to top and second rings measured by fixed point LIF method Fig.1-6 Oil transport on the second land in the circumferential direction(12rpm-no load) 6

Fig.1-7 Scanning LIF system 7

Fig.1-8 Instantaneous oil film thickness distribution in ring-land region 8

Pressure Mpa Oil film thickness 4 2 2 16 12 36 18 18 36 Crank angle deg. (a) 1rpm motoring Pressure Mpa Oil film thickness 4 2 2 16 12 36 18 18 36 Crank angle deg. (c) 1rpm Full laod Oil film thickness Pressure Mpa 4 2 2 16 12 36 18 18 36 Crank angle deg. (b) 2rpm motoring Pressure Mpa Oil film thickness 4 2 2 16 12 36 18 18 36 Crank angle deg. () 2rpm Full load Fig.1-9 Minimum of oil film thickness at the top ring Under motoring and firing operation 1-2-2 PIV 9

U U X t 1

Fig.1-1 Surface roughness on the Test Plate ( ) U Oil film thickness Friction force m N N Crank angle 24rpm 76kN/m 2 (a) Journal factor U Fig.1-11 Example of test result (21) (Test face No4,Viscosity.216Pas) Crank angle 6rpm 151kN/m 2 (b) Journal factor U 11

FURUHAMAREYNOLDS SEPARATION SEPARATION U U U Fig.1-12 Theoretical boundary condition model on piston ring oil film (21) Fig.1-13 Comparison of calculated result and test result (21) (Plate No.4,Viscocity.26Pa-s,12rpm,5kN/m 2, Journal Factor;2.37 1 - ) Fig.1-12 12

Friction force N Cal.(with fcav) Cal.(without fcav) 6rpm 12rpm 2rpm 9 BDC 27 TDC 9 9 BDC 27 9 9 BDC 27 TDC 9 Crank angle deg. Crank angle deg. Crank angle deg. Fig1-14 Characteristics of friction forces on ƒcav b u b dx f cav x x h U y xr h xr 2 13

LIFPIV 15

2 LIF Cuomarin6 He-Cd 18

Piston 1st ring 2nd ring 3rd ring Oil iinjection Glass cylinder Nd;YAG Laser Filter CCD Camera Rotary encoder Power source Engine controller Oil pass PIV processor Computer Oil return Oil tank Pump Fig.2-1 LIF Measurement system of oil film thickness on the test engine. Table2-1 Experimental engine specifications NAME MEGATECH MARK Engine Cycle 4 cycle Cylinder 1 cyl Bore Stroke(mm) 41.2 5.8 Compression Ratio 4:1 Operation Motoring Engine LIF 3 rpm5rpm Rev. PIV 1rpm Cooling Air 19

Piston cap Piston cap Top ring 2nd ring Top land 2nd land 3rd land 3rd ring Fig.2-2 Piston configuration of an experimentally model engine 2

Table2-2 Lubrication oil specifications SEA #3 CD Class #3 Additive wt% 8.5 Base Oil 5SN wt% 1 73. Density(15 )g/cm 3.884.887 KV 1mm 2 /sec 1.94 1.87 KV 4 mm 2 /sec 96.97 9.28 VI 97 15 Sulfated Ash wt%.77 TBN(HClO4)mg KOH/g 6.4 21

Fig. 2-3 LIF image by using slid glasses Fig.2-4 Experimentally setup verification of oil film thickness Fig.2-5 Fluorescence intensity and oil film thickness with various Dye concentration 22

Fluorescence intensity 25 2 15 1 5.1 g g/l / Rhodamine B 25 5 75 1 125 5 1 15 2 25 3 Oil film thickness m Fig.2-6 Relationship between fluorescence intensity and oil film thickness on temperature 23

Fluorescence Flourescence intensity 25 2 15 1 5 (b)2. g/l 2./ Rhodamine B 25 75 125 5 1 5 1 15 2 25 3 Oil film thickness μm Fig.2-7 Relationship between fluorescence intensity and oil film thickness on temperature Fig.2-8 Example of feeler gauge for oil film thickness calibration 24

Oil with RhodaminB.1g/ Glass cylinder Fig.2-9 Calibration method of cylinder with feeler gauge Fluorescence intensity 25 2 15 1 5 Resin surface Metal surface 5 1 15 2 Oil film thickness μm Fig. 2-1 Relationship between fluorescence intensity and oil film thickness in crystal cylinder 25

LIF Piston cap Top land Top ring 2nd land 3rd land 3rd ring Clank Angle deg. (TDC) Clank Angle 9deg. Clank Angle 18deg. (BDC) Fig.2-11 Oil film thickness on piston of suction stroke.) 3rd (TDC)(BDC) BDC18 27 36 TDC 26

Top ring 2nd ring Piston cap Top land 2nd land 3rd land 3rd ring Clank Angle 18deg(BDC). Clank Angle 27deg. Clank Angle 36deg. (TDC) Fig.2-12 Oil film thickness on piston of compression stroke Top ring 2nd ring Piston cap Top land 2nd land 3rd land 2nd land 3rd ring Clank Angle 36deg. (TDC) Clank Angle 45deg. Clank Angle 54deg. (BDC) Fig.2-13 Oil film thickness on piston of expansion stroke 27

Piston cap Top ring 2nd ring Top land 2nd land 3rd land 3rd ring 72deg Clank Angle 54deg. (BDC) Clank Angle 63deg. Clank Angle 72deg. (TDC) Fig.2-14 Oil film thickness on piston of exhaust stroke 28

Oil film thickness μm 1 8 6 4 2 Suction Compression Expansion Exhaust piston cap2 top ring second ring third ring Fig.2-15 Variation of oil film thickness on the piston rings with crank angle TDC BDC TDC BDC TDC 9 18 27 36 45 54 63 72 Crank angle deg. 29

(5),(6) 3

. 33

3 PIV PIV U U X t F.3- PIV Principal method 4 34

Fig.3-2 PIV Messurment flow chart (4) 36

Pixel pitch Fig.3-3 Sub pixel correlation (4) 37

Piston Glass cylinder Nd;YAG Laser Power source 2nd ring Filter 3rd ring Oil iinjection Slit 1mm CCD Camera Engine controller Rotary encoder PIV processor Oil pass Computer Oil return Oil tank Pump Fig.3-4 PIV Messurment system Lighting system PIV camera External signals Input buffer Synchronism unit Correlation unit PIV processor Measured data/set up Personal computer Fig.3-5 Block diagram of PIV system 38

38. 1.6 47. a b c 14.5 13.2 1. 135. 41.2 a,b,c,4.8mm Fig.3-6 Piston and piston-rings for PIV measurement 4

a9deg.(suction stroke). (b) 27deg.(Compression stroke ) Fig.3-7 Oil film vector maps around piston ring slit by PIV 41

Slit V(m/s).3.27.24.21.18.15.12.9.6.3. -.3 -.6 -.9 -.12 -.15 -.18 -.21 -.24 -.27 -.3 (a)deg(tdc) (b) 9 deg.(max.speed) (c) 18 deg(bdc) Fig.3-8 Contour map of oil film velocity with 2nd ring on suction stroke ( 4 Y mm 3 2 1 1 2 3 4 X mm 1 2 3 4 X mm (a) 21 deg (b) 27 deg.(max.speed) 1 2 3 4 X mm (c) 36deg.(TDC) V(m/s).3.27.24.21.18.15.12.9.6.3. -.3 -.6 -.9 -.12 -.15 -.18 -.21 -.24 -.27 -.3 Fig.3-9 Contour map of oil film velocity with 2nd ring on compression stroke 42

Y mm 4 3 2 1 1 2 3 4 1 2 3 4 1 2 3 4 X mm X mm X mm (a) 39 deg (b) 45 deg.(max.speed) (c) 54 deg.(bdc) Fig.3-1 Contour map of film velocity with 2nd ring on expansion stroke V(m/s).3.27.24.21.18.15.12.9.6.3. -.3 -.6 -.9 -.12 -.15 -.18 -.21 -.24 -.27 -.3 Y mm 4 3 1 1 2 3 4 X mm 1 2 3 4 X mm 1 2 3 4 X mm (a) 57 deg (b) 63 deg.(max.speed) (c) 72deg.(TDC) V(m/s).3.27.24.21.18.15.12.9.6.3. -.3 -.6 -.9 -.12 -.15 -.18 -.21 -.24 -.27 -.3 Fig.3-11 Contour map of oil film velocity with 2nd ring on exhaust stroke 43

V m/s.3.2.1. -.1 9 deg. 18 deg. 27 deg. 36 deg. -.2 -.3 1 2 3 4 5 Measuring position mm Fig.3-12 Oil film velocity distribution with various crank angle 44

V m/s.3.2.1. -.1 -.2 Suction Compression Expansion Exhaust Vpt Vp Voc Vo -.3 9 18 27 36 45 54 63 72 TDC BDC TDC BDC TDC Crank angle deg. Fig.3-13 Velocity of oil film and piston with crank angle 45

RCA29 48

LIFPIV 3 2nd NdYAG RhodamineB Glass cylinder Power source Piston NdYAG Laser 2nd rng 3rd ring Oil Injection Notch filter CCD Camera Rotary encoder Oil pass PIV Processor Computer Oil return Oil tank Pump Fig4-1 Measurement system of LIF and PIV combination method 49

Fig,4-2 Test equipment of model engine 5

1.5/s 1.5/s Fig.4-3Velocity map of Rhodamine B.1g/ Fig.4-4 Velocity map of Rhodamine B.5g/ 52

Table4-3 Horizontally opposite test engine specifications and engine operation NAME Cycle Cylinder Experimental horizontally opposite engine 4 cycle 2 cylinder Bore Stroke(mm) 96.9 75. Compression ratio 9.5:1 Engine Rev. Operation Motoring Firing Cooling Motoring,Firing 8rpm,12rpm, 16rpm 12rpm Air 53

Fig.4-5 Piston specification of EJ22 Type 922 test engine. Table4-4 Piston rings specification Piston ring configuration BT Ring tension N Top ring 1.23.3 8.2 2nd ring 1.53.7 5.4 Oil ring 3.3.1 34. Total ring tension N 47.6 54

Horizontally opposite test engine Nd:YAG Laser Power source Mirror CCD Camera Notch filter Engine controller Rotary encoder PIV Processor Computer Fig,4-6 Measurement system by LIF and PIV Combinations method 55

Nd:YAG laser Engine with sapphire cylinder CCD Camera Fig.4-7 Experimental equipment for measuring LIF and PIV on the test engine Mirror Sapphire cylinder Rugate Notch filter CCD Camera EJ22 Horizontally opposite engine Fig.4-8 EJ22 Type922 Engine and measuring instrument 56

Fig.4-9 Fig.4-9 Calibration jig Feeler guage Lubrication oil Calibration jig Feeler gauge Sapphire cylinder Fig. 4-1 Example of calibration method 57

135. 16. -3de -2de -1de de 1de 2de 3de (a) Poin of calibration Sapphire cylinder (b)phot.of jig Feeler gauge Fig.4-11 Calibration method of oil film thickness and intensity 58

Fluorescence Intensity Fluorescence Intensity 25 Fluorescence Intensity 2 15 15 1 1 5 5 25 2 15 1 5 deg_ deg_ deg_ (a)cylinder deg.angle 1 2 3 4 5 6 7 8 9 1 11 Oil Film Thickness (μm) 12.5deg. 12.5deg. 12.5deg. Oil film thickness(μm) (c)cylinder 12.5deg.angle 1 2 3 4 5 6 7 8 9 1 11 Oil film thickness(μm) Fluorescence Intensity Fluorescence Intensity 2 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 1 1 11 11 Oil Oil film Film thickness(μm) Thickness 1 2 3 4 5 6 7 8 9 1 11 Oil film thickness(μm) Fig4-12 Calibration of oil film thickness and intensity with Rhodamine B 25 25 15 15 1 1 5 5 1deg. 1deg. 1deg. 25-3.deg. 2-3.deg. -3.deg. 15 1 5 (b)cylinder 1deg.angle (d)cylinder -3.deg.angle Oil hole Piston Center e 12.5deg. 3.deg. Fig.4-13 Measuerement point of oil film thickness and intensity on the piston 59

Fig.4-14 Cylinder pressure under motoring and firing operation on the test engine 6

1 12rpm mm 1 Piston skirt Top ring 2nd ring mm 1 3rd ring Oil hole 5 5 mm 1mm 5 1 mm Crank angle 1deg. 3rd land 5 1 Crank angle1deg. mm 1 2 4 6 8 1 12 5 Unit Cylinder 5 1 Crank angle 16deg. mm Fig.4-15-(1) Oil film thickness distribution obtained by LIF at suction stroke under motoring operation (engine speed 12rpm) 61

2 12rpm mm 1 Piston skirt 2nd ring mm 1 5 5 5 1 mm 1mm mm 5 1 Crank angle 28deg. mm 1 Cylinder 2 4 6 8 1 12 5 Unit 5 1 Crank angle34deg.. mm Fig.4-15-(2) Oil film thickness distribution obtained by LIF at compression stroke under motoring operation (engine speed 12rpm) 62

12rpm mm mm 1 Piston skirt Top ring 2nd ring 3rd ring Oil hole 1 5 5 3rd land 5 1 mm 1mm Crank angle 46deg. mm 5 1 Crank angle 37deg mm 1 5 2 4 6 8 1 12 Unit Cylinder 5 1 Crank angle 52deg. mm Fig.4-15-(3) Oil film thickness distribution obtained by LIF on expansion stroke under motoring operation (engine speed 12rpm) 63

12rpm ( ) mm mm 1 Piston skirt Top ring 2nd ring 3rd ring Oil hole 1 5 5 3rd land 1mm 5 1 Crank angle 55deg. mm 5 1 mm Crank angle 64deg. mm 1 Cylinder 2 4 6 8 1 12 5 Unit 5 1 Crank angle 7deg. mm Fig.4-15-(4) Oil film thickness distribution obtained by LIF on exhaust stroke under motoring operation (engine speed 12rpm) 64

Oil O film i l f ilm thickness t h ic k n e s s [ μm μ m ] 14 12 1 8 6 4 2 1st 2nd 3rd 4th Crank angle 1deg () Oil ring 2nd ring Top ring Oil film thickness μm 14 12 1 8 6 4 2 1st 2nd 3rd 4th Crank angle 1deg () Oil ring 2nd ring Top ring Oil O film f thickness t h n e s s [μ m μm ] 14 12 1 8 6 4 2 6 3μm 4 1st 2nd 3rd 4th 4 2 Measurement Measurement position position mm Crank angle 1DEG (1) 2nd land 3rd land Top land Oil O il film lm thickness k n e s s [ μ μm m ] 6 2 3μm Measurement position mm 14 12 1 8 6 4 2 1st 2nd 3rd 4th Crank angle 1deg () 3rd land Top land Oil O il film f m thickness t h k n e s s [ μm μ m ] 6 14 12 1 8 6 4 2 1st 2nd 3rd 4th 4 Measurement 2 Measurement position mm Crank angle 16deg.() 6μm 6 14 12 Oil O ifilm l lm thickness t h k n e s s [μ μm m ] 1 8 6 4 2 1st 2nd 3rd 4th 4 2 Measurement position mm Crank angle 16deg.() 6μm 6 4 6 4 2 Measurement position 2 3μm Measurement position mm Measurement position Measurement position mm 6μm Fig.4-16-(1) Oil film thickness on the piston and ring at suction stroke 65

Oil film thickness μm Oil film thickness μm 14 12 1 8 6 4 2 14 12 1 8 6 4 2 Oil O i l film f i l m thickness t h i c k n e s s [ μm μ m ] 6 6 14 12 1 8 6 4 2 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th Crank angle 19deg Oil ring 4 Measurement position Crank angle 28deg 4 2 Measurement position mm Oil film thickness μm 2 mm Crank angle 34deg. 2nd ring Top ring 3μm 5μm Oil film thickness μm Oil film thickness μm Oil O i l film f i l m thickness t h i c k n e s s [ μm μ m ] 6 4 2 Measurement position 6 4 2 Measurement position mm 3μm 3μ Measurement position mm Fig.4-16-(2) Oil film thickness on the piston and ring at compression stroke 14 12 1 8 6 4 2 6 14 12 1 8 6 4 2 14 12 1 8 6 4 2 6 1st 2nd 3rd 4th 1st 2nd 3rd 4th 1st 2nd 3rd 4th Crank angle19deg () Oil ring 4 2 Measurement position mm Crank angle 28deg 4 2 Measurement position mm Crank angle 34deg 2nd ring Top ring 6μm 6μm 66

14 12 Oil film thickness μm Oil O il film f ilm thickness t h k n e s s [μ μm m ] O il f ilm th ic k n es s [μ m ] 1 8 6 4 2 6 14 12 1 8 6 4 2 1st 2nd 3rd 4th Crank angle 37deg Oil ring 4 2 Measurement position mm 2nd ring Top ring 1st 2nd 3rd 4th 6μm Crank angle46deg Oil O film f tthickness h k n e s s [μ μm m ] Oil O il film f ilm thickness k n s [μ μm m ] 14 12 1 8 6 4 2 6 14 12 1 8 6 4 2 1st 2nd 3rd 4th 1st 2nd 3rd 4th Crank angle 37deg Oil ring 4 2 Measurement position mm Crank angle 46deg 2nd ring Top ring Oil O Oil fil m film th i c thickness k n e s s [ μ m ] μm 14 12 1 8 6 4 2 6 1st 2nd 3rd 4th 4 2 Measurement 6μm 6 4 2 Measurement position mm Measurement Measurement position mm 14 Crank angle 52deg 1st 12 2nd 3rd 1 4th Oil O il film m thickness i c k n e s s [ μ μm m ] 8 6 4 2 Crank angle 52deg 6μm 6 4 2 positon 6 4 2 Measurement position mm Cra 5μm Measurement position mm 6μm Fig.4-16-(3) Oil film thickness on the piston and ring at expansion stroke 67

Oil O film thickness k n s [μ m μm ] 14 12 1 8 6 4 2 1st 2nd 3rd 4th Crank angle 55deg Oil ring 2nd ring 2ring Top ring Oil O il film f m thickness k n e s s [ μ μm m ] 14 12 1 8 6 4 2 1st 2nd 3rd 4th 2 Oil ring 2nd ring 2ring Top ring O Oil film m thickness i c k n e s s [ μ m μm ] 6 14 12 1 8 6 4 1st 2nd 3rd 4th 4 2 Measurement Measurement position mm Crank angle 64deg Cran 5μm 6 Oil film thickness μm 8 6 4 1st 2nd 3rd 4th 4 4 2 Measurement Measurement position mm Crank angle 64deg 6μm 2 2 6 4 2 Measurement position mm 5μm 6 4 Measurement position mm 6μm Oil O film f thickness k n s [μ μm m ] 14 12 1 8 6 4 2 1st 2nd 3rd 4th Crank angle 7deg Oil O il film f thickness t h k n e s s [μ μm m ] 14 12 1 8 6 4 2 1st 2nd 3rd 4th Crank angle 7deg 6 4 2 Measurement position mm 2μm 6 4 2 Measurement position mm 6μm Fig.4-16-(4) Oil film thickness on the piston and ring at exhaust stroke 68

Oil film thickness m Suction Compression Expansion Exhaust -3.deg.() (TDC) (BDC) (TDC) (BDC) (TDC) Crank angle deg. 12.5deg.() Fig.4-17 Oil film thickness around the top ring under motoring operation LIF, PIV 7

Piston moving direction 2m/s 2m/s 4deg 1degabout TDC 2m/s 2m/s 1deg.(about max.speed) 7deg 2m/s 2m/s 16deg.(about BDC) 13deg Fig,.4-18-(1) Oil film velocity maps at the suction stroke under motoring operation (12rpm) 71

Piston moving direction 2m/s 2m/s 19deg.(about BDC) 22deg 2m/s 2m/s 25deg 28deg.(about max.speed) 2m/s 2m/s 31deg 34deg.(about TDC) Fig.4-18-(2) Oil film velocity maps at the compression stroke under motoring operation ( 12rpm) 72

Piston moving direction 2m/s 2m/s 4deg 37deg.(about TDC) 2m/s 2m/s 46deg. 43deg(about max. speed) 2m/s 2m/s 52deg. 49deg Fig,4-18-(3) Oil film velocity maps at the expansion stroke under motoring operation- (12rpm) 73

Piston moving direction 2m/s 2m/s 55deg.(about BDC) 58deg. 2m/s 2m/s 61deg. 64deg.(about max. speed) 2m/s 2m/s 67deg 7deg.(about TDC) Fig,.4-18-(4) Oil film velocity maps at the exhaust stroke under motoring operation (12rpm) 74

V m/s 8 4-4 Expansion Stroke 8rpm 8rpm_Vpt 12rpm 12rpm_Vpt 16rpm 16rpm_Vpt Exhaust Stroke 64deg(max.speed) -8 44deg(max.speed) 36 42 48 54 6 66 72 (TDC) (BDC) (TDC) Crank angle deg. Fig.4-19 Oil film velocity and theoretical piston velocity with various engine speeds. V V - V Vpt pt m/s m/s.3.2.1. -.1 -.2 3deg. 8 12 16 Expansion Stroke Piston direction Exhaust Stroke VOil film velocity VptTheoretical piston velocity 3deg. Piston direction -.3 TDC BDC 36 42 48 54 6 66 72 Crank angle deg TDC Fig,.4-2 Relative velocity between oil film (V)and piston(vpt) 77

Y X 4mm Oil ring Center (3rd ring) Oil hole Fig4-21.Measurement point of oil film velocity on 3rd ring and piston skirt 79

Piston speed Piston speed mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 1deg. mm Oil ring gap Velocity of oil film on skirt Crank angle 1deg. mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 1deg. Oil ring gap Velocity of oil film on skirt Crank angle 1deg V m/s V m/s V m/s V m/s V m/s V m/s mm 16deg mm mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 16deg. Oil ring gap Velocity of oil film on skirt Crank angle 16deg. Fig.4-22-(1) Velocity of il film on 3rd ring and skirt at suction stroke(12rpm) 8

V m/s V m/s Piston speed mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 19deg. V m/s V m/s Piston speed mm Oil ring gap Velocity of oil film on skirt Crank angle 19deg. mm mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 28deg. Oil ring gap Velocity of oil film on skirt Crank angle 28deg. V m/s V m/s mm mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 34deg. 81 Oil ring gap Velocity of oil film on skirt Crank angle 34deg. Fig4-22-(2) Velocity of oil film on 3rd ring and skirt at compression stroke(12rpm)

Piston speed Piston speed V m/s V m/s V m/s mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 37deg. mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 46deg. V m/s V m/s V m/s mm Oil ring gap Velocity of oil film on skirt Crank angle 37deg. mm Oil ring gap Velocity of oil film on skirt Crank angle 46deg. 52deg (1.3) mm mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 52deg. Oil ring gap Velocity of oil film on skirt Crank angle 52deg. Fig4-22-(3) Velocity of oil film on 3rd ring and skirt at expansion stroke(12rpm) 82

( V m/s V m/s 55dg(.65 ) Piston speed mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 55deg. V m/s V m/s Piston speed mm Oil ring gap Velocity of oil film on skirt Crank angle 55deg. mm mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 64deg. Oil ring gap Velocity of oil film on skirt Crank angle 64deg. V m/s V m/s mm mm Oil ring gap Velocity of oil film on 3rd ring Crank angle 7deg. Oil ring gap Velocity of oil film on skirt Crank angle 7deg. Fig4-22-(4) Velocity of oil film on 3rd ring and skirt at exhaust stroke(12rpm) 83

Suction Compression Expansion Exhaust V m/s 6 4 2 Advanced point -2-4 Advanced point Advanced point Piston Velocity Advanced point -6 6 12 18 24 3 36 42 48 54 6 66 72 Crank angle deg. Fig4-23 Relationship velocity between piston and oil film velocity of 3rd ringpiston skirt under motoring operation(12rpm) V / Vpt 1.2 1.15 1.1 1.5 1..95.9.85.8 31deg. 31deg. 31deg. 31deg. Crank angle deg. Vs / Vpt Vo / Vpt 18 36 54 72 (TDC) (BDC) (TDC) (BDC) (TDC) Fig4-24 Vs/Vpt,Vo/Vpt change with crank angle under motoring operation (12rpm) 86

V m/s V m/s mm mm Oil ring gap Fig.4-25-(1) Oil film velocity at 3rd ring on crank angle 46deg. under motoring (12rpm) Oil ring gap Fig4-25-(2) Oil film velocity at 3rd ring on crank angle 46deg. under firing (12rpm) 87

V m/s V m/s mm mm Oil ring gap Fig4-26-(1) Oil film velocity at piston skirt on crank angle 46deg.under motoring (12rpm) Oil ring gap Fig4-26-(2) Oil film velocity at piston skirt on crank angle 46deg. under firing (12rpm) 88

26 92

5 Table5-1 Horizontally opposite engine specifications and engine operation NAME Horizontally opposite engine Cycle 4 cycle Cylinder & Volume 4 cylinder, 1.267 Bore Stroke(mm) 82. 6. Compression ratio 9.:1 Operation Motoring Engine Motoring Rev. 1rpm6rpm Rev.Load Load Full Load Oil cooling system Water Con.rod length& r/= 12mm&=.25 93

Table5-2 Lubrication oil specification SEA #3 Additive wt% Base Oil 5SN wt% 1 Density(15 )g/cm 3.884 KV 1mm 2 /s 1.94 KV 4 mm 2 /s 96.97 VI 97 Sulfated Ash wt% TBN(HClO4)mg KOH/g Table5-3 Piston rings specification Piston ring configuration B Ring tension N Top ring 2. 15. 2nd ring 2. 16. Oil ring 4. 51. Total ring tension N 82. 94

Fig.5-1 Measured system of friction losses on horizontally opposite engine 95

Horizontally opposite engine Mean effective friction pressure Pa Engine speed rpm Fig.5-2 Friction losses in each sliding component 97

5-2-4 () W p Cp (μ ω /W p ) 98

Friction coefficient f o p / W p Fig.5-3 Stribeck diagram R f R r R p R r f r W r f r W r R r W r W r W r BP x P r 99

Piston Cylinder Fig.5-4 The force of rings pushing against each cylinder Fig.5-4 The force of ring pushing against each cylinder ω π/3 n E rsinθρ/2sin2θ R r π /3 Cr D r n E Σ{B(P x + P r )} - sinθρ/2sin2θ R p f p ( )tanφ =P πd /4 (W/g)( π/3 ne)2 r{cosθ+ρ/2cos2θ} tansinρsinθ Fig.5-5 The force of a piston body 1

Fig.5-6 The force of pushing cylinder contracting with a piston and the contact angle between them. f p = Cr ( ω/ W p ) W p W p ( )tanφ /(Dδp/2) R p Cp π/6 D r n E δp ρ 1- sinθρ/2sin2θ sinθ[(π/4)dp+(1/g)( π/3) 2 (r/d)wn E 2 {cosθρ/2cos2θ}] - R f ±R r R p R f ±D (r n E ) sinθρ/2sin2θ [(π /3Cr Σ{B(P x + P r )} - Cp π/6 (π/4) - D - δp ρ 1- sinθ[p+(1/g)4/ππ/3) 2 (r/d )Wn E 2 {cosθρ/2cos2θ}] - ] 4 24 2 1 1 P fm n E D r w p R f d 4 11

PV PV n = GRT = constant Fig.5-7 P-V diagram V V V 1 1 4 3 V G G a V s P P = R a T 2 (ℇ-1) -(n-1) ( V/Vs ) -n 2 V s 12

P = R a T 3 (ℇ-1) -(n-1) ( V/Vs ) -n VV S /{(1-cosθ)+(ρ/4)(1-cos2θ)+2/(ε-)} 1 m 1 m 1 m P fm D r n C ( BP ) ( BP ) +Cr 2 { B T η V (ε-1) } - 1 m 1 m 1 m n 1 m m m T T C B P 1 T T 2 n 1 1 m 1 m m 1 m 1 m C rd m 1 m C p 2 p D V 1 T 2 T n 1 m 2 m m 1 Wn T T V E 3 r 1 r 3 E r r 2 T V 3 r T 3 2 p 3 p 3 C p 1 m p r D 1 m n 2 2 m E (1) Mean effective friction pressure Pa Engine speed rpm Fig.5-8 Measured value of friction losses of the piston system 13

Mean effective friction pressure Pa Exhaust 5 Kinematics viscosity of oil Fig.5-9 Measured value of friction losses othe piston system.5 P fm υ 1.25 14

C r1 1.33C r2 1.8C r3.14 C p1 1.4 1 C p2.142c p3 R 2.5.5.5.6 B Px Pr.12D p r 2 sin P.14 Wn E cos cos D 2.5.5.5 f Dr ne sin sin 2.5 2 2.5 P fm.5 rne.5.5 1.33 BPr BPr T D.25.5.5.5.5.25 1.8 B. 5 1 T2 T3.14 B Pr 1 T.5.5 3 1.5 T 2 T3.14 1 p Wr D ne.25.5.5..5.142 p D 1 T 2 T3 Cylinder pressure MPa 5. 4. 3. 2. 1. Spark timing 24deg.BTDC Full load No load BDC Compression TDC Expansion BDC Fig.5-1 Measured value of cylinder pressure 15

Suction Compression Expansion Exhaust Piston friction N N 1.3l horizontally opposite engine Engine speed: 5rpm,Full load Lubricating oil; SAE#3 Oil temperature: 11 Total friction at firing Total friction t motoring Piston ring friction (No pressure at cylinder) Fig.5-11 Results of calculation of friction losses on a piston system 16

Suction Compression Expansion Exhaust Piston friction N Diesel engine 1cyliner BS;137125mm Engine Speed;1rpm Furuhama s experimental result at full load Calculated Result at full load Calculated Result at full load (No pressure at cylinder) Fig.5-12 Comparison between calculated piston friction and the measured results by Furuhama s Diesel engine 4 17

Table5-4 Specification of EK56 type engine Type EK56 Straight engine Total displacement.55 Cylinder bore stroke 76mm 6mm Number of cylinders 2 Compression ratio 9.3 : 1 Cooling method Water-cooled Main materials Cast iron (aluminum for pistons) 8. 3 ring package 2 ring package NSRNarrow Single Ringpiston Fig.5-13 Each piston in 2 cylinder test engine 18

Table5-5 Piston rings specification of test engine Ring configuration & Tension Standard 2 ring package NSR 2 ring package Tension=8.5N Tension=18.3N Tension=18.3N Tension=12.N Tension=34.N Tension=34.N Tension=9.1N 19

Piston Floating liner Liner supporter Piezo type load washer Gas seal O-ring O-ring holder O-ring holder Upper part lateral stopper Lower part lateral stopper Fig.5-14 Measuring flouting cylinder device of piston frictional forces () 11

111, 3 1 m 2 2 E 2 2 cos 2 cos D r n W g 1 3 4 P sin m m m e m f 2 sin 2 sin n Dr R m 1 m p m 1 m 1 m ' p m 1 ' r m m 1 D 4 6 C P P B C 3 m 1 T r m 1 r r1 m E 1 fm BP 1 1BP C rn D P m 1 3 m 1 2 m 1 1 ) n ( 2 r T T 1 B 1C m 3 m 2 m 1 ) n ( T m 1 3 r T T 1 p B C 2m 2 E m 1 m p pl n D r 1C m 1 3 m 1 2 m 1 1 ) n ( m p 2 p T T 1 D 1C m ) 1 ( m 1 m p 3 1C p rd m 3 m 2 2 E m 1 ) n ( T T Wn 1

2 cylinder engine (.55) Lubricating oil SAE#3 Mean effective friction Pressure Pa Engine speed rpm Fig.5-15 Measured value of friction losses on piston assembly Cr =.6, Cp =.18, Cr 1 =.167, Cr 2 =.714, Cr 3 =.553 1, Cp 1 =.27 1 Cp 2 =.374 Cp 3 = 112

.5.5.5 R f Dr n E sin sin 2 2.5.5.5.5.192 B Px Pr.115D P r 2 sin P.14 Wn cos cos2 2 D E 2.5.5 P fm.5.5.25.25.5.5.423 BPr Bp r 5.71B T v 1 ( T2 T3 ) T.5.25.5.5.5.5.43( B Pr ) T v 1 ( T2 T3 ) 21.6 1 W D n E r n. 5 D E.5 -.25.5.5 3. D - 1) T T p v 2 3 113

Suction Compression Expansion Exhaust Cylinder internal pressure MPa Piston friction N Crank Angle Fig.5-16 Piston frictional force diagram. Standard 3 ring package 1rpmTc=9 114

(2) Suction Compressio Expansion Exhaust Cylinder internal pressure MPa Piston friction N Crank Angle Fig.5-17 Piston frictional force diagram. Standard 3 ring package 2rpm Tc=9 115

Suction Compression Expansion Exhaust Cylinder internal pressure MPa Piston friction N Crank Angle Fig.5-18 Piston frictional force diagram. Standard 3 ring package 3rpm Tc=9 116

Suction Compression Expansion Exhaust Cylinder internal pressure MPa Piston friction N Crank angle Fig.5-19 Piston frictional force diagram. Standard 3 ring package 2rpm Tc=6 117

Suction Compression Expansion Exhaust Cylinder internal pressure MPa Piston friction N Crank angle Fig.5-2 Piston frictional force diagram. Standard 2 ring package 2rpm,Tc=9 118

Suction Compression Expansion Exhaust Cylinder internal pressure MPa Piston friction N Crank angle Fig.5-21 Piston frictional force diagram. NSR 2 ring package 2rpm (Tc=9) 119

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( 1 )C ( 2 )C 6 123

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LIF PIV 131

2 4 2 BP OEM 2 132