Open y-yosuke opened 8 years ago
Front Fender Stay - Louver / Pressure
Front Fender Stay - Louver / fp-023c Control - Coefficients Comparison
Body and Wheels
Coef. | fp-023c Control | Fr Fender Stay Louver | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0781 | 0.0580 | -0.0200 | -25.7 | |
Cd | 0.5590 | 0.5594 | +0.0004 | +0.1 | |
Cl | -0.1693 | -0.1856 | -0.0164 | -9.7 | |
Clf | -0.0066 | -0.0348 | -0.0282 | -430.8 | |
Clr | -0.1627 | -0.1509 | +0.0118 | +7.3 | |
CoP | 0.9613 | 0.8127 | -0.1486 | -14.9 | |
L/D | -0.3028 | -0.3318 | -0.0291 | -9.6 |
Body Only
Coef. | fp-023c Control | Fr Fender Stay Louver | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0610 | 0.0397 | -0.0212 | -34.8 | |
Cd | 0.4385 | 0.4356 | -0.0028 | -0.6 | |
Cl | -0.2099 | -0.2277 | -0.0178 | -8.5 | |
Clf | -0.0440 | -0.0741 | -0.0301 | -68.5 | |
Clr | -0.1659 | -0.1536 | +0.0123 | +7.4 | |
CoP | 0.7904 | 0.6745 | -0.1159 | -11.6 | |
L/D | -0.4787 | -0.5227 | -0.0440 | -9.2 |
S-Duct B / fp-023c Control (S-Duct) - Coefficients Comparison
Body and Wheels
Coef. | fp-023c Control | S-Duct B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0781 | 0.0829 | +0.0048 | +6.2 | |
Cd | 0.5590 | 0.5599 | +0.0009 | +0.2 | |
Cl | -0.1693 | -0.1698 | -0.0006 | -0.3 | |
Clf | -0.0066 | -0.0020 | +0.0045 | +68.9 | |
Clr | -0.1627 | -0.1678 | -0.0051 | -3.1 | |
CoP | 0.9613 | 0.9880 | +0.0267 | +2.7 | |
L/D | -0.3028 | -0.3034 | -0.0006 | -0.2 |
Body Only
Coef. | fp-023c Control | S-Duct B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0610 | 0.0657 | +0.0047 | +7.8 | |
Cd | 0.4385 | 0.4389 | +0.0004 | +0.1 | |
Cl | -0.2099 | -0.2101 | -0.0002 | -0.1 | |
Clf | -0.0440 | -0.0394 | +0.0046 | +10.5 | |
Clr | -0.1659 | -0.1708 | -0.0049 | -2.9 | |
CoP | 0.7904 | 0.8126 | +0.0222 | +2.2 | |
L/D | -0.4787 | -0.4788 | -0.0001 | -0.0 |
S-Duct B (N=800)
forces forces00 output:
sum of forces:
pressure : (193.182943654 -211.1175369 -64.6585533378)
viscous : (16.9342055983 -1.1612082756 0.918214639582)
porous : (0 0 0)
sum of moments:
pressure : (82.9307102155 73.2037344004 85.9220588796)
viscous : (-0.115295623349 9.22704317281 10.9899892581)
porous : (0 0 0)
forceCoeffs forceCoeffs02 output:
Cm = 0.0656816313594
Cd = 0.4388667238
Cl = -0.210138970477
Cl(f) = -0.0393878538793
Cl(r) = -0.170751116598
forceCoeffs forceCoeffs01 output:
Cm = 0.0828843945401
Cd = 0.559874576087
Cl = -0.169841420538
Cl(f) = -0.00203631572878
Cl(r) = -0.167805104809
S-Duct B / fp-023c Control (S-Duct) - Pressure and U-Magnitude Comparison
Surface Pressure
Y=0mm Pressure Y=-120mm Pressure
Y=0mm U-Magnitude
Coefficients Comparison for GitHub Issues - Google Drive Spreadsheet https://docs.google.com/spreadsheets/d/16RVkg4-Oiqgl5CmZgXSQ4busL_FCBbx4LxGmaFLLxrU/edit?usp=sharing
Front Fender Louver C + Louver Stay / fp-023c Control - Coefficients Comparison
Body and Wheels
Coef. | fp-023c Control | Fr Fender Louver C + Louver Stay | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0781 | 0.0428 | -0.0353 | -45.2 | |
Cd | 0.5590 | 0.5683 | +0.0093 | +1.7 | |
Cl | -0.1693 | -0.2051 | -0.0358 | -21.2 | |
Clf | -0.0066 | -0.0598 | -0.0532 | -812.3 | |
Clr | -0.1627 | -0.1453 | +0.0174 | +10.7 | |
CoP | 0.9613 | 0.7086 | -0.2527 | -25.3 | |
L/D | -0.3028 | -0.3609 | -0.0581 | -19.2 |
Body Only
Coef. | fp-023c Control | Fr Fender Louver C + Louver Stay | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0610 | 0.0231 | -0.0378 | -62.0 | |
Cd | 0.4385 | 0.4433 | +0.0049 | +1.1 | |
Cl | -0.2099 | -0.2586 | -0.0487 | -23.2 | |
Clf | -0.0440 | -0.1061 | -0.0622 | -141.3 | |
Clr | -0.1659 | -0.1524 | +0.0135 | +8.1 | |
CoP | 0.7904 | 0.5895 | -0.2009 | -20.1 | |
L/D | -0.4787 | -0.5833 | -0.1046 | -21.8 |
Front Fender Louver C + Louver Stay (N=800)
forces forces00 output:
sum of forces:
pressure : (195.849018972 -213.976414436 -78.0798080457)
viscous : (17.4363679765 -1.06542027951 1.11178466513)
porous : (0 0 0)
sum of moments:
pressure : (90.8645614662 32.6684863908 90.3038405582)
viscous : (-0.300541654383 9.87526980512 11.4990146828)
porous : (0 0 0)
forceCoeffs forceCoeffs02 output:
Cm = 0.0231455610287
Cd = 0.443333425557
Cl = -0.258590762715
Cl(f) = -0.106149820329
Cl(r) = -0.152440942386
forceCoeffs forceCoeffs01 output:
Cm = 0.0427778746916
Cd = 0.568316608275
Cl = -0.20508768378
Cl(f) = -0.0597659671982
Cl(r) = -0.145321716581
Front Fender Louver C + Louver Stay - Flow Vector
Slice at Y=-520mm
Front Fender Louver C + Louver Stay B / Front Fender Louver C + Louver Stay - Coefficients Comparison
Body and Wheels
Coef. | Fr Fender Louver C + Louver Stay | Fr Fender Louver C + Louver Stay B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0428 | 0.0496 | +0.0068 | +15.8 | |
Cd | 0.5683 | 0.5622 | -0.0061 | -1.1 | |
Cl | -0.2051 | -0.1990 | +0.0061 | +3.0 | |
Clf | -0.0598 | -0.0499 | +0.0098 | +16.5 | |
Clr | -0.1453 | -0.1490 | -0.0037 | -2.5 | |
CoP | 0.7086 | 0.7491 | +0.0405 | +4.0 | |
L/D | -0.3609 | -0.3539 | +0.0070 | +1.9 |
Body Only
Coef. | Fr Fender Louver C + Louver Stay | Fr Fender Louver C + Louver Stay B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0231 | 0.0300 | +0.0068 | +29.5 | |
Cd | 0.4433 | 0.4401 | -0.0033 | -0.7 | |
Cl | -0.2586 | -0.2515 | +0.0071 | +2.7 | |
Clf | -0.1061 | -0.0958 | +0.0104 | +9.8 | |
Clr | -0.1524 | -0.1557 | -0.0033 | -2.2 | |
CoP | 0.5895 | 0.6192 | +0.0297 | +3.0 | |
L/D | -0.5833 | -0.5716 | +0.0117 | +2.0 |
Front Fender Louver C + Louver Stay B (N=800)
forces forces00 output:
sum of forces:
pressure : (193.594173988 -212.110703092 -75.7760171924)
viscous : (17.3917652795 -1.08442962181 1.11069449078)
porous : (0 0 0)
sum of moments:
pressure : (89.2308128353 39.431771951 87.3466997841)
viscous : (-0.291788799091 9.8484672478 11.4303927196)
porous : (0 0 0)
forceCoeffs forceCoeffs02 output:
Cm = 0.0299764568244
Cd = 0.440050754546
Cl = -0.251531019826
Cl(f) = -0.0957890530888
Cl(r) = -0.155741966738
forceCoeffs forceCoeffs01 output:
Cm = 0.0495514285929
Cd = 0.562189539161
Cl = -0.198951946782
Cl(f) = -0.049924544798
Cl(r) = -0.149027401984
Front Fender Louver C + Louver Stay B /Front Fender Louver C + Louver Stay Flow Vector, U-Magnitude, Pressure Comparison
Flow Vector - Slice at Y=-520mm
U Magnitude - Slice at Y=-520mm
Pressure on the body
Front Fender Louver C + Louver Stay B / fp-023c Control - Coefficients Comparison
Body and Wheels
Coef. | fp-023c Control | Fr Fender Louver C + Louver Stay B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0781 | 0.0496 | -0.0285 | -36.5 | |
Cd | 0.5590 | 0.5622 | +0.0032 | +0.6 | |
Cl | -0.1693 | -0.1990 | -0.0297 | -17.5 | |
Clf | -0.0066 | -0.0499 | -0.0434 | -662.1 | |
Clr | -0.1627 | -0.1490 | +0.0137 | +8.4 | |
CoP | 0.9613 | 0.7491 | -0.2122 | -21.2 | |
L/D | -0.3028 | -0.3539 | -0.0511 | -16.9 |
Body Only
Coef. | fp-023c Control | Fr Fender Louver C + Louver Stay B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0610 | 0.0300 | -0.0310 | -50.8 | |
Cd | 0.4385 | 0.4401 | +0.0016 | +0.4 | |
Cl | -0.2099 | -0.2515 | -0.0416 | -19.8 | |
Clf | -0.0440 | -0.0958 | -0.0518 | -117.7 | |
Clr | -0.1659 | -0.1557 | +0.0102 | +6.1 | |
CoP | 0.7904 | 0.6192 | -0.1712 | -17.1 | |
L/D | -0.4787 | -0.5716 | -0.0929 | -19.4 |
Ride Height Analysis 110mm - 110mm : Done 90mm - 110mm : Done
One more run, which set should I choose? 90mm - 90mm? 90mm - 100mm? 80mm - 100mm? 70mm - 90mm? 70mm - 100mm?
Probably 90-90.
Ride Height : Front 90mm - Rear 110mm / Front 110mm - Rear 110mm Coefficients Comparison(fp-023c Control + Front Fender Louver C + Louver Stay B)
Body and Wheels
Coef. | RH110-110 | RH90-110 | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0496 | 0.0221 | -0.0274 | -55.3 | |
Cd | 0.5622 | 0.5641 | +0.0020 | +0.3 | |
Cl | -0.1990 | -0.2544 | -0.0554 | -27.9 | |
Clf | -0.0499 | -0.1051 | -0.0551 | -110.4 | |
Clr | -0.1490 | -0.1493 | -0.0003 | -0.2 | |
CoP | 0.7491 | 0.5870 | -0.1621 | -16.2 | |
L/D | -0.3539 | -0.4509 | -0.0970 | -27.4 |
Body Only
Coef. | RH110-110 | RH90-110 | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0300 | 0.0036 | -0.0264 | -88.1 | |
Cd | 0.4401 | 0.4380 | -0.0021 | -0.5 | |
Cl | -0.2515 | -0.3013 | -0.0498 | -19.8 | |
Clf | -0.0958 | -0.1471 | -0.0513 | -53.6 | |
Clr | -0.1557 | -0.1542 | +0.0015 | +1.0 | |
CoP | 0.6192 | 0.5118 | -0.1073 | -10.7 | |
L/D | -0.5716 | -0.6880 | -0.1164 | -20.4 |
Ride Height Front 90mm - Rear 110mm - Front Fender Louver C + Louver Stay B (N=800)
forces forces00 output:
sum of forces:
pressure : (194.291186818 -213.825979718 -96.6543773514)
viscous : (17.4300011885 -1.07900206673 1.19017166119)
porous : (0 0 0)
sum of moments:
pressure : (95.3464649842 12.3364344072 86.3704867995)
viscous : (-0.351573823555 9.66856081282 11.492471991)
porous : (0 0 0)
forceCoeffs forceCoeffs02 output:
Cm = 0.00356647633311
Cd = 0.437982707814
Cl = -0.301326842985
Cl(f) = -0.14709694516
Cl(r) = -0.154229897826
forceCoeffs forceCoeffs01 output:
Cm = 0.0221260888149
Cd = 0.564148670425
Cl = -0.254372296039
Cl(f) = -0.105060059204
Cl(r) = -0.149312236834
Ride Height : Front 90mm - Rear 110mm / Front 110mm - Rear 110mm U Magnitude, Pressure Comparison ( fp-023c Control + Front Fender Louver C + Louver Stay B )
U Magnitude : Slice at Y=-800mm
U Magnitude : Slice at Y=0mm
Pressure : Bottom View
Ride Height : Front 90mm - Rear 90mm / Front 90mm - Rear 110mm Coefficients Comparison(fp-023c Control + Front Fender Louver C + Louver Stay B)
Body and Wheels
Coef. | RH90-110 | RH90-90 | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0221 | 0.0503 | +0.0282 | +127.3 | |
Cd | 0.5641 | 0.5562 | -0.0080 | -1.4 | |
Cl | -0.2544 | -0.2487 | +0.0057 | +2.2 | |
Clf | -0.1051 | -0.0741 | +0.0310 | +29.5 | |
Clr | -0.1493 | -0.1746 | -0.0253 | -17.0 | |
CoP | 0.5870 | 0.7022 | +0.1153 | +11.5 | |
L/D | -0.4509 | -0.4472 | +0.0037 | +0.8 |
Body Only
Coef. | RH90-110 | RH90-90 | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0036 | 0.0309 | +0.0274 | +767.2 | |
Cd | 0.4380 | 0.4362 | -0.0018 | -0.4 | |
Cl | -0.3013 | -0.2923 | +0.0091 | +3.0 | |
Clf | -0.1471 | -0.1152 | +0.0319 | +21.7 | |
Clr | -0.1542 | -0.1771 | -0.0228 | -14.8 | |
CoP | 0.5118 | 0.6058 | +0.0940 | +9.4 | |
L/D | -0.6880 | -0.6701 | +0.0179 | +2.6 |
Ride Height Front 90mm - Rear 90mm - Front Fender Louver C + Louver Stay B (N=800)
forces forces00 output:
sum of forces:
pressure : (191.36126958 -212.379017721 -94.5543844719)
viscous : (17.362086193 -1.03766758448 1.22020061593)
porous : (0 0 0)
sum of moments:
pressure : (92.4888905742 40.5730247486 88.3599140732)
viscous : (-0.397104898237 9.44665486222 11.446518923)
porous : (0 0 0)
forceCoeffs forceCoeffs02 output:
Cm = 0.0309300065483
Cd = 0.436155655602
Cl = -0.292254122391
Cl(f) = -0.115197054647
Cl(r) = -0.177057067744
forceCoeffs forceCoeffs01 output:
Cm = 0.0502949381491
Cd = 0.55616069773
Cl = -0.248696676149
Cl(f) = -0.0740533999252
Cl(r) = -0.174643276223
Ride Height : Front 90mm - Rear 90mm / Front 110mm - Rear 110mm Coefficients Comparison(fp-023c Control + Front Fender Louver C + Louver Stay B)
Body and Wheels
Coef. | RH110-110 | RH90-90 | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0496 | 0.0503 | +0.0007 | +1.5 | |
Cd | 0.5622 | 0.5562 | -0.0060 | -1.1 | |
Cl | -0.1990 | -0.2487 | -0.0497 | -25.0 | |
Clf | -0.0499 | -0.0741 | -0.0241 | -48.3 | |
Clr | -0.1490 | -0.1746 | -0.0256 | -17.2 | |
CoP | 0.7491 | 0.7022 | -0.0468 | -4.7 | |
L/D | -0.3539 | -0.4472 | -0.0933 | -26.4 |
Body Only
Coef. | RH110-110 | RH90-90 | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0300 | 0.0309 | +0.0010 | +3.2 | |
Cd | 0.4401 | 0.4362 | -0.0039 | -0.9 | |
Cl | -0.2515 | -0.2923 | -0.0407 | -16.2 | |
Clf | -0.0958 | -0.1152 | -0.0194 | -20.3 | |
Clr | -0.1557 | -0.1771 | -0.0213 | -13.7 | |
CoP | 0.6192 | 0.6058 | -0.0133 | -1.3 | |
L/D | -0.5716 | -0.6701 | -0.0985 | -17.2 |
atan(20/2650) = 0.432 [deg] Wheel Base : 2650 mm
Ride Height : Front 90mm - Rear 90mm / Front 90mm - Rear 110mm U Magnitude Comparison(fp-023c Control + Front Fender Louver C + Louver Stay B)
Slice at Y=-1mm
Slice at Y=-100mm
Slice at Y=-200mm
Slice at Y=-300mm
Slice at Y=-400mm
Slice at Y=-500mm
Slice at Y=-600mm
Slice at Y=-700mm
Slice at Y=-800mm
Slice at Y=-900mm
Slice at Y=-1000mm
Slice at Y=-1100mm
Slice at Y=-1200mm
fp-023c Control + Front Fender Louver C + Louver Stay B / Ride Height : 90-110mm Contour : k=7 (Turbulent kinetic energy value [m²/s²])
fp-023c Control + Front Fender Louver C + Louver Stay B / Ride Height : 90-110mm Contour : k=10 [m^2/s^2]
【 fp-023c - Summary of the Results (Part 1) 】
I found a low pressure area on the upper surface of the front fender. It seemed to generate a lift force like a aircraft wing coupled with the high pressure in the wheel house. So I thought that a louver may be effective for eliminating the pressure difference between the upper and lower surfaces of the front fender.
I tested 3 types of louver below in the simulations.
The shapes of these louvers are shown below along with the pressure value from the simulations.
A table comparing the coefficients obtained from the simulation are shown below. As it shows, "Fr Fender Louver C" is most effective with the biggest front downforce and the small drag increase.
Coefficients of the forces on the body and wheels
Coef. | fp-023c Control | Fr Fender Louver | Fr Fender Louver B | Fr Fender Louver C | Remarks |
---|---|---|---|---|---|
Cm | 0.0781 | 0.0696 | 0.0611 | 0.0600 | |
Cd | 0.5590 | 0.5619 | 0.5636 | 0.5619 | |
Cl | -0.1693 | -0.1805 | -0.1930 | -0.1964 | |
Clf | -0.0066 | -0.0206 | -0.0354 | -0.0383 | |
Clr | -0.1627 | -0.1599 | -0.1576 | -0.1582 | |
CoP | 0.9613 | 0.8858 | 0.8168 | 0.8052 | |
L/D | -0.3028 | -0.3212 | -0.3424 | -0.3496 |
Coefficients of the forces on the body (without wheels)
Coef. | fp-023c Control | Fr Fender Louver | Fr Fender Louver B | Fr Fender Louver C | Remarks |
---|---|---|---|---|---|
Cm | 0.0610 | 0.0512 | 0.0417 | 0.0406 | |
Cd | 0.4385 | 0.4430 | 0.4445 | 0.4418 | |
Cl | -0.2099 | -0.2242 | -0.2416 | -0.2450 | |
Clf | -0.0440 | -0.0609 | -0.0791 | -0.0819 | |
Clr | -0.1659 | -0.1633 | -0.1625 | -0.1631 | |
CoP | 0.7904 | 0.7285 | 0.6726 | 0.6657 | |
L/D | -0.4787 | -0.5060 | -0.5434 | -0.5546 |
These louvers generate flows from the lower side of front fender to upper as seen in the pictures below.
U Magnitude Comparison at Y=-800mm
Stream Lines - Front Fender Louver
Stream Lines - Front Fender Louver B
Stream Lines - Front Fender Louver C
【 fp-023c - Summary of the Results (Part 2) 】
I found the front fender stay was installed so as to go against the flow and it seemed to generate a lift force. Therefore I designed other stays that do not inhibit the flow.
I tested 2 types of stays below in the simulations.
The shapes of these stays are shown below along with the pressure value from the simulations.
Upper View
Lower View
The both new 2 stays increas the front downforce. The "Stay - Louver" is less drag than "Stay - Oval Tubes".
Coefficients of the forces on the body and wheels
Coef. | fp-023c Control | Stay - Oval Tubes | Stay - Louver | Remarks |
---|---|---|---|---|
Cm | 0.0781 | 0.0610 | 0.0580 | |
Cd | 0.5590 | 0.5618 | 0.5594 | |
Cl | -0.1693 | -0.1863 | -0.1856 | |
Clf | -0.0066 | -0.0322 | -0.0348 | |
Clr | -0.1627 | -0.1542 | -0.1509 | |
CoP | 0.9613 | 0.8274 | 0.8127 | |
L/D | -0.3028 | -0.3317 | -0.3318 |
Coefficients of the forces on the body (without wheels)
Coef. | fp-023c Control | Stay - Oval Tubes | Stay - Louver | Remarks |
---|---|---|---|---|
Cm | 0.0610 | 0.0427 | 0.0397 | |
Cd | 0.4385 | 0.4383 | 0.4356 | |
Cl | -0.2099 | -0.2282 | -0.2277 | |
Clf | -0.0440 | -0.0714 | -0.0741 | |
Clr | -0.1659 | -0.1568 | -0.1536 | |
CoP | 0.7904 | 0.6872 | 0.6745 | |
L/D | -0.4787 | -0.5207 | -0.5227 |
The comparison figures of "U magnitude" and "Flow Vector" are shown below. The flow of "Stay - Louver" seems smoothest.
U Magnitude Comparison at Y=-520mm
Flow Vector Comparison at Y=-520mm
【 fp-023c - Summary of the Results (Part 3) 】
From the comparison of the flow vector of the front fender stays, I thought a louver type stay could reduce the drag more. Therefore I designed another louver stay "Louver Stay B".
The shapes of "Louver Stay B" is shown below along with the pressure value from the simulations. ( Probably these shapes seem almost the same. / "Louver Stay" = "Stay - Louver")
The drag and front downforce of "Louver Stay B" are less than those of "Louver Stay". But I think these differences are too small to be judged.
Coefficients of the forces on the body and wheels
Coef. | Louver Stay + Fr Fender Louver C | Louver Stay B + Fr Fender Louver C | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0428 | 0.0496 | +0.0068 | +15.8 | |
Cd | 0.5683 | 0.5622 | -0.0061 | -1.1 | |
Cl | -0.2051 | -0.1990 | +0.0061 | +3.0 | |
Clf | -0.0598 | -0.0499 | +0.0098 | +16.5 | |
Clr | -0.1453 | -0.1490 | -0.0037 | -2.5 | |
CoP | 0.7086 | 0.7491 | +0.0405 | +4.0 | |
L/D | -0.3609 | -0.3539 | +0.0070 | +1.9 |
Coefficients of the forces on the body (without wheels)
Coef. | Fr Fender Louver C + Louver Stay | Fr Fender Louver C + Louver Stay B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0231 | 0.0300 | +0.0068 | +29.5 | |
Cd | 0.4433 | 0.4401 | -0.0033 | -0.7 | |
Cl | -0.2586 | -0.2515 | +0.0071 | +2.7 | |
Clf | -0.1061 | -0.0958 | +0.0104 | +9.8 | |
Clr | -0.1524 | -0.1557 | -0.0033 | -2.2 | |
CoP | 0.5895 | 0.6192 | +0.0297 | +3.0 | |
L/D | -0.5833 | -0.5716 | +0.0117 | +2.0 |
The flow of "Louver Stay B" seems smoother a little than that of "Louver Stay".
Flow Vector at Y=-520mm
U Magnitude at Y=-520mm
At this moment, I think "Louver Stay B" is the best for the following reasons.
【 fp-023c - Summary of the Results (Part 4) 】
The aero-device "S-Duct" at the nose cone ( simulated in "fp-023b - Front Aero Devices / Simulation - S-Duct : https://www.simscale.com/projects/yosukegb4/fp-023b_control/ ", the coefficients are shown below ) shifts the rear dowonforce to the front and decreases the drag a little.
Coefficients of the forces on the body and wheels
Coef. | fp-023b Control | S-Duct | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.1330 | 0.1228 | -0.0102 | -7.7 | |
Cd | 0.5510 | 0.5488 | -0.0022 | -0.4 | |
Cl | -0.1550 | -0.1579 | -0.0029 | -1.8 | |
Clf | 0.0555 | 0.0438 | -0.0117 | -21.0 | |
Clr | -0.2105 | -0.2017 | +0.0088 | +4.2 | |
CoP | 1.3579 | 1.2776 | -0.0803 | -8.0 | |
L/D | -0.2813 | -0.2876 | -0.0063 | -2.2 |
This "S-Duct" was just one case in the simulation of "fp-023b - Front Aero Devices". Therefore I would like to see the reactivity due to a different design of the S-Duct. I designed "S-Duct B" that inlet is 150mm forward than the original "S-Duct". The difference is shown below.
Difference between "S-Duct B" and "S-Duct (fp-023c Control)"
The device "S-Duct B" shifts the front downforce to the rear compared with "S-Duct (fp-023c Control)". It does not meet the target to distribute the downforce more to the front.
Coefficients of the forces on the body and wheels
Coef. | S-Duct (fp-023c Control) | S-Duct B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0781 | 0.0829 | +0.0048 | +6.2 | |
Cd | 0.5590 | 0.5599 | +0.0009 | +0.2 | |
Cl | -0.1693 | -0.1698 | -0.0006 | -0.3 | |
Clf | -0.0066 | -0.0020 | +0.0045 | +68.9 | |
Clr | -0.1627 | -0.1678 | -0.0051 | -3.1 | |
CoP | 0.9613 | 0.9880 | +0.0267 | +2.7 | |
L/D | -0.3028 | -0.3034 | -0.0006 | -0.2 |
Coefficients of the forces on the body (without wheels)
Coef. | S-Duct (fp-023c Control) | S-Duct B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0610 | 0.0657 | +0.0047 | +7.8 | |
Cd | 0.4385 | 0.4389 | +0.0004 | +0.1 | |
Cl | -0.2099 | -0.2101 | -0.0002 | -0.1 | |
Clf | -0.0440 | -0.0394 | +0.0046 | +10.5 | |
Clr | -0.1659 | -0.1708 | -0.0049 | -2.9 | |
CoP | 0.7904 | 0.8126 | +0.0222 | +2.2 | |
L/D | -0.4787 | -0.4788 | -0.0001 | -0.0 |
Surface Pressure
Pressure at Y=0mm
U Magnitude at Y=0mm
【 fp-023c - Summary of the Results (Part 5) 】
The combination of "Front Fender Louver C" and "Louver Stay B" was simulated.
These increase the downforce without much increasing the drag and distribute the downforce to the front more.
Coefficients of the forces on the body and wheels
Coef. | fp-023c Control | Fr Fender Louver C + Louver Stay B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0781 | 0.0496 | -0.0285 | -36.5 | |
Cd | 0.5590 | 0.5622 | +0.0032 | +0.6 | |
Cl | -0.1693 | -0.1990 | -0.0297 | -17.5 | |
Clf | -0.0066 | -0.0499 | -0.0434 | -662.1 | |
Clr | -0.1627 | -0.1490 | +0.0137 | +8.4 | |
CoP | 0.9613 | 0.7491 | -0.2122 | -21.2 | |
L/D | -0.3028 | -0.3539 | -0.0511 | -16.9 |
Coefficients of the forces on the body (without wheels)
Coef. | fp-023c Control | Fr Fender Louver C + Louver Stay B | Difference | Difference % | Remarks |
---|---|---|---|---|---|
Cm | 0.0610 | 0.0300 | -0.0310 | -50.8 | |
Cd | 0.4385 | 0.4401 | +0.0016 | +0.4 | |
Cl | -0.2099 | -0.2515 | -0.0416 | -19.8 | |
Clf | -0.0440 | -0.0958 | -0.0518 | -117.7 | |
Clr | -0.1659 | -0.1557 | +0.0102 | +6.1 | |
CoP | 0.7904 | 0.6192 | -0.1712 | -17.1 | |
L/D | -0.4787 | -0.5716 | -0.0929 | -19.4 |
【 fp-023c - Summary of the Results (Part 6) 】
The aero-devices set of the simulations for the ride heights comparison is "fp023c Control + Fr Fender Louver C + Louver Stay B". The value of "Reference area value [m²]" are the same "0.645" for the all ride height simulations.
The positive rake angle and the lower ride height make more downforce as same as other general formula cars. And the horizontal attitudes and the lower ride height reduce the drag.
Coefficients of the forces on the body and wheels
Coef. | RH110-110 | RH90-110 | RH90-90 | Remarks |
---|---|---|---|---|
Cm | 0.0496 | 0.0221 | 0.0503 | |
Cd | 0.5622 | 0.5641 | 0.5562 | |
Cl | -0.1990 | -0.2544 | -0.2487 | |
Clf | -0.0499 | -0.1051 | -0.0741 | |
Clr | -0.1490 | -0.1493 | -0.1746 | |
CoP | 0.7491 | 0.5870 | 0.7022 | |
L/D | -0.3539 | -0.4509 | -0.4472 |
Coefficients of the forces on the body (without wheels)
Coef. | RH110-110 | RH90-110 | RH90-90 | Remarks |
---|---|---|---|---|
Cm | 0.0300 | 0.0036 | 0.0309 | |
Cd | 0.4401 | 0.4380 | 0.4362 | |
Cl | -0.2515 | -0.3013 | -0.2923 | |
Clf | -0.0958 | -0.1471 | -0.1152 | |
Clr | -0.1557 | -0.1542 | -0.1771 | |
CoP | 0.6192 | 0.5118 | 0.6058 | |
L/D | -0.5716 | -0.6880 | -0.6701 |
These seem almost the same below, but the differences seen around the edges of the reference plane, on the bottom surfaces of the front wing, between the front fender louver and the front wheel and so on.
Pressure on the body and wheels - Bottom View
U Magnitude at Y=-1mm
U Magnitude at Y=-100mm
U Magnitude at Y=-200mm
U Magnitude at Y=-300mm
U Magnitude at Y=-400mm
U Magnitude at Y=-500mm
U Magnitude at Y=-600mm
U Magnitude at Y=-700mm
U Magnitude at Y=-800mm
U Magnitude at Y=-900mm
U Magnitude at Y=-1000mm
U Magnitude at Y=-1100mm
U Magnitude at Y=-1200mm
【 fp-023c - Summary of the Results (Part 7) 】
As in the results of "Front Fender Louver C + Louver Stay B" and "Ride Height Comparison", I achieved the goal to distribute the front and rear downforces of the body to be about 60-65%. ( Clf : Clr = 40-35 : 60-65 )
As a next step, I would like to develop the rear aero-devices as shown below and so on.
CFDの結果を信じる限りにおいてはフロントのダウンフォースが足りないらしい. https://github.com/y-yosuke/formula-ppoino/issues/11#issuecomment-233866299
なのでフロントダウンフォースの増加策を考える. https://github.com/y-yosuke/formula-ppoino/issues/11#issuecomment-233886791 の続き.
Monocoque ドライバ足下の面を水平に→ 座席法規 400mm x 400mm の確保が難しいFr Wing - Fender の縦のつながりの部位外側にダクト15〜20mmCFD 解析をして大雑把な傾向を見ながら開発を進める.
とりあえず S-Duct ほい.