Shelby GT-500. Super Charger Low Temperature Cooling Loop

Transcription

1 Shelby GT-500 Super Charger Low Temperature Cooling Loop

2 Roush Power Train Systems Engineering has been tasked to devise a production solution world wide for extended driving at a constant Boost level. Ambient temperature range: Test #1 Test #2 Test #3 98 f 110 f 120 f (series of ten sessions would be conducted at each test temperature) Duty cycle, Road load 0 % grade and max speed 155+mph. Sign off requirements Engine oil temp. not to exceed 305 f Intermittent 280 f Extended Transmission temp. not to exceed 300 f Intermittent 280 f Extended Air Charge Temperature ( ACT 2 ) 180 f Extended

3 Problem - High ACT 2 at boost levels > 3psi. : Shelby GT 500 to achieve / maintain (ACT 2) temperatures of 180 deg. f Or less during extended boost levels of 8 PSI for 10 minutes. Two row 19mm tube design was chosen over the single 24 mm tube design. Coolant Pump would be carry over 4 GPM. Carry over pump control logic for pump on to pump off set points. Mounting locations would be carry over from previous years PROBLEM / REASON FOR TESTING: Investigate a foaming problem with the 50/50 Glycol during the first minutes of testing. ( see graph during the first 170 seconds )

4 Testing Requirements Road Load 0% grade: Precondition for 20 minutes at 85 mph to stabilize coolant and running gear temperatures. Drop speed to 65 mph and apply dynamometer load to exercise Supercharger to 8 PSIG. Boost and maintain for 10 minutes Air Charge Temperature (ACT 2) not to exceed 180 deg f. NOTE: Super Charger - Low Temperature Cooling Loop is also commonly named pre-intercooler.

5 Evaluation steps: Contact coolant suppliers and inquire about a coolant or additive package that would curtail the foaming issue and have better heat transfer capability. A low ambient was deemed not a requirement as this would be a moderate to high temperature package only. SynMax Lubricants (Water Kooler), Competitive Coolant Additive Products & Prestone (50/50 Glycol premix) all supplied chemical fluids for evaluation.

6 Evaluation Steps: Three series of ten tests with each product at the atmospheric inlet temperatures of: Test #1: 98 deg. f Test #2: 110 deg. f Test #3 120 deg. f A larger non production degas bottle was chosen for testing after the first ten were completed as all the products tested exhibited a foaming issue. After Final Test #3 120 deg f ( ten session completed) the Coolant fluid that showed little to no foam was the Water Kooler from Synmax Lubricants. Synmax Water Kooler also showed a better heat transfer rate than the 50/50 glycol mixture. Expectation was that Synmax Water Kooler would be closer than 20+ deg. f cooler which was measured and achieved.

7 The following graph (s) shows (Delta-T) performance Delta T performance is the average difference between the inlet and outlet temperatures Higher (Delta-T ) factor = Greater Cooling Effect and Efficiency Synmax Water Kooler Concentrate with purified / distilled water ( 100 PREMIX ) INLET deg f / OUTLET deg. f Average delta T (inlet- outlet ) deg. f NOTE: Synmax Water Kooler Product - performed best as compared to all others tested. Prestone -Glycol 50/50 Mixture INLET deg f / OUTLET deg. f Average delta T (inlet- outlet ) deg. f 50/50 Vs water Kooler Delta T water kooler Delta T Delta T time in seconds

8 50/50 Vs water Kooler Delta T water kooler Delta T Delta T time in seconds

9 Synmax Water Kooler / Distilled Water (100% Premix) Air speed at core face 4 m/s ( Pre-Intercooler - Front of Radiator ) Average air temp deg. f Average coolant inlet temp deg. f Average coolant outlet temp deg. f Average Delta-T (inlet- outlet ) deg. f

10 water kooler Delta T deg f 20 water kooler Delta T time seconds

11 50/50 Glycol & Pure Water Air speed at core face 4 m/s ( Pre-Intercooler - Front of Radiator ) Average air temp deg. f Average coolant inlet temp deg. f Average coolant outlet temp deg. f Average Delta-T (inlet- outlet ) deg. f

12 50/50 Glycol and water Delta T Delta T time in seconds

13 Synmax Water Kooler Performance Summary Super Charger Intercooler (engine) Pre-Intercooler in front of Radiator (Lower Temperature Cooling Loop) Data & Overall Performance Close to Radiator Coolant System Synmax Water Kooler showed Heat Transfer improvement (15%-20%) As Compared to 50/50 Glycol and Other competitive coolant products. Resulting in 20 deg. f Lower Temps.

14 Shelby GT-500 Super Charger Low Temperature Cooling Loop Presentation- END.