Stealth CATs

Eric BuddriusAmanda BollandIan LootensGreg HilbertStealth CATs

Specifications

CatalystAristo Contact is Bob McDowellGoal: to meet National Park Standards Focus: Carbon Monoxide and Unburned Hydrocarbons emissions

Emissions Data2010 ResultsCSC LimitNPS BATCO 209.94< 275< 120HC41.6-< 15NOX5.8--HC+NOX47.36< 90-E-Score125.9> 100-Units: g/kW-hrMuffler BasicsTwo Main FunctionsReflectionMost EffectiveDestructive InterferenceHigh Back PressureRestrictionMost CommonCheapestAbsorptionSimple with Low Back PressureLow Damping

Hushpower technology

Entry Cone

B. Laminar Flow Area

C. Thermal Barrier

D. Exit ConeDesign EvaluationFlow BenchRicardo WaveJ 192 Testing ProcedureTimeline

Flow Bench

Test StandSettling ChamberMass Flow MeterVacuum Supply

Flow BenchActive Flow BenchVacuum sourceTest PartMultiple usesCylindersPortingMufflersAir filtersMeasuresPressure differential with respect to mass flowWhat is Ricardo Wave?

Mufflers in Ricardo Wave

Ricardo WNoise

Ricardo Wnoise output

J 192 Sound Test

SOUND TestingExisting MufflerLaminar Flow MufflerHushpower Muffler Affect of PackingSmall vs. Large Cone PerforationSeriesParallel

TimelineNovember 29th Start J192 Sound Testing of Existing MufflersDecember 10th Complete Flow BenchDecember 15th Flow Test Existing MufflersDecember 17th Final Muffler DesignedJanuary 15th Receive Final CATJanuary 21st Final Muffler BuiltJanuary 22nd Begin Testing Final Muffler on SledMarch 4th Leave for Competition

Questions?