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COOLING SYSTEMS

If you did your homework, this will make more sense!. If you didn’t, get it turned late tomorrow. COOLING SYSTEMS. AUTO 1. We will take notes in a little bit. HEAT. WHAT MAKES AN ENGINE RUN?. NO! WHAT REALLY MAKES AN ENGINE RUN?. WHERE DOES THE HEAT COME FROM?. THAT’S RIGHT, BURNING FUEL.

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COOLING SYSTEMS

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  1. If you did your homework, this will make more sense! If you didn’t, get it turned late tomorrow. COOLING SYSTEMS AUTO 1 We will take notes in a little bit.

  2. HEAT WHAT MAKES AN ENGINE RUN? NO! WHAT REALLY MAKES AN ENGINE RUN?

  3. WHERE DOES THE HEAT COME FROM? THAT’S RIGHT, BURNING FUEL • HEAT CAUSES EXPANSION WHICH CAUSES? • PRESSURE! • PRESSURE PUSHES PISTON DOWN WHICH MAKES THE WHEELS GO ROUND AND ROUND ENERGY……….

  4. ELECTRICAL CHEMICAL NUCLEAR THERMAL RADIANT MECHANICAL TYPES OF ENERGY

  5. FUEL IS CHEMICAL ENERGY WHEN BURNED COVERTS TO... THERMAL ENERGY (HEAT) WHICH CAUSES EXPANSION (PRESSURE) WHICH COVERTS TO… MECHANICAL ENERGY WHICH WE USE TO MOVE THINGS THIS IS ENERGY CONVERSION

  6. REMEMBER, YOU CAN’T CREATE OR DESTROY ENERGY YOU CAN ONLY CHANGE ITS FORM THIS IS ENERGY CONVERSION IN OTHER WORDS, THERE IS ONLY SO MUCH ENERGY HERE ON EARTH AND WE CAN’T ADD TO IT OR RUN OUT OF IT. NEVER USE IT UP! WOW ENERGY CONVERSION?

  7. FUEL IS CHEMICAL ENERGY WHEN BURNED COVERTS TO... THERMAL ENERGY (HEAT) WHICH CAUSES EXPANSION (PRESSURE) WHICH COVERTS TO… MECHANICAL ENERGY WHICH WE USE TO MOVE THINGS WE HAD BETTER WRITE THIS DOWN IN OUR FUEL NOTES.

  8. YOU CAN’T CREATE OR DESTROY ENERGY, YOU CAN ONLY CHANGE ITS FORM! ITS FORM IS CHANGED BY A CHEMICAL REACTION. THE MOST COMMON TYPE OF CHEMICAL REACTION IS COMBUSTION LETS MOVE ON

  9. HEAT IS THE RAPID MOVEMENT OF ATOMS OR MOLECULES IN A SUBSTANCE ABSOLUTE 0 IS-460F (-273C) HEAT IS A FORM OF ENERGY HEAT IS MEASURED BY………. TEMPERATURE DEGREES IN FAHRENHEIT OR CELSIUS BTU’s VOLUME OF HEAT HEAT LETS CONCENTRATE ONWE HAD BETTER WRITE THESE DOWN IF WE DON’T ALREADY KNOW THEM

  10. BRITISH THERMAL UNIT ONE (1) BTU WILL RAISE THE TEMPERATURE OF ONE (1) POUND OF WATER ONE (1) DEGREE FAHRENHEIT (F) BTU,s ????

  11. TEMPERATURE IS THE DEGREE OF HEAT OR HOW HOT. FOR EXAMPLE, A MATCH MIGHT BURN AT 400 DEGREES F. BTU IS THE VOLUME OF HEAT OR HOW MUCH, BUT NOT TEMPERATURE. EXAMPLE, THE AMOUNT HEAT IT TAKES TO HEAT THIS ROOM, OR RAISE THE TEMPERATURE OF THIS ROOM WHAT IS THE DIFFERENCE BETWEEN TEMPERATURE AND BTU,s ?

  12. COMBUSTION TEMPERATURES CAN REACH UP TO __________ DURNING THE COMBUSTION PROCESS. PAGE 92 OF YOUR HOMEWORK. THINK ABOUT THIS QUESTION BEFORE YOU FORM AN ANSWER. WOULD YOU WANT THE VOLUME OF HEAT FROM ONE 6000 DEGREE F POWER STROKE TO HEAT THIS ROOM? NOT IN THE WINTER TIME

  13. DO WE HAVE THE IDEA OF THE DIFFERENCES BETWEEN TEMPERATURE OF HEAT AND VOLUME OF HEAT?

  14. ONE GALLON OF GASOLINE HAS APPROXIMATELY 115,000 BTU,s. THAT MEANS THE AVERAGE GALLON OF GASOLINE HAS THE ENERGY TO RAISE THE TEMPERATURE OF ONE POUND OF WATER 115,000 DEGREES F. (IMPOSSIBLE) OR… RAISE 115,000 LBS OF WATER ONE DEGREE F. OR RASIE 1,150 LBS OF WATER (ABOUT 150 GALS.) 100 DEGREES F. GALLON OF GASOLINE

  15. OTHER FUELS HAVE DIFFERENT BTU,s DIESEL HAS APPROXIMAELY 135,000 BTU,s PER GALLON ALCOHOL HAS APPROXIMATELY 85,000 BTU,s PER GALLON

  16. HOW DOES THE ENGINE USE THIS ENERGY?

  17. ONE GALLON115,000 BTU COST $1.30 - $1.60

  18. LOST TO EXHAUST 35% LOST OUT EXHAUST

  19. LOST TO COOLING LOST TO EXHAUST 35% LOST TO COOLING SYSTEM

  20. FRICTIONAL LOSSES 15% LOST TO FRICTIONAL LOSSES LOST TO COOLING LOST TO EXHAUST

  21. WOW FRICTIONAL LOSES LOST TO COOLING APPROXIMATELY 15% LEFT TO MOVE THE CAR. LOST TO EXHAUST

  22. WHAT A WASTE!!!!!

  23. IF TODAYS VEHICLES CAN AVERAGE 20 MILES PER GALLON NOW USING JUST 15% OF THE ENERGY IN A GALLON OF FUEL... WHAT KIND OF MILAGE COULD THEY GET IF WE COULD IMPROVE IT TO 50% OF THE ENERGY IN A GALLON OF FUEL???

  24. TODAY 20 MPG USING 15% OF ENERGY TOMMOROW?? 70 MPG USING 50% OF ENERGY MILES PER GALLON AVERAGES

  25. SO WHY DO WE HAVE TO REMOVE 35% OF THE HEAT WITH A COOLING SYSTEM? WE JUST PAID BIG MONEY TO BUY FUEL TO CREATE HEAT! LIMITED BY CURRENT MATERIAL TECHNOLOGY LIMITED BY CURRENT LUBRICATION TECHNOLOGY

  26. CYLINDER WALL TEMPERATURE MUST BE KEPT BELOW 500 DEGREES F.WHY? OIL BREAKS DOWN (BURNS) CAN YOU SAY DRY FRICTION?

  27. HEAT TRANSFERMAKE SURE YOU GET THIS IN YOUR NOTES THE MOVEMENT OF HEAT FROM ONE PLACE TO ANOTHER

  28. THREE TYPES OF HEAT TRANSFER CONDUCTION CONVECTION RADIATION

  29. CONDUCTION TRANSFER OF HEAT THRU SOLIDS

  30. CONVECTION TRANSFER OF HEAT THRU LIQUIDS OR VAPORS

  31. RADIATION TRANSFER OF HEAT THRU LIGHT RAYS

  32. EXPERIMENT TIME

  33. DAY TWO

  34. CAN’T DESTROY OR CREATE ENERGY ENERGY CONVERSION SIX TYPES OF ENERGY IN AUTOMOBILES WE USE, ELECTRICAL, THERMAL, CHEMICAL, RADIANT, AND MECHANICAL. DON’T USE NUCLEAR HEAT WHAT IT IS AND HOW IT IS MEASURED DIFFERENCES BETWEEN TEMP AND BTU LETS REVIEW

  35. DIFFERENT FUELS HAVE DIFFERENT ENERGY CONTENT (BTU) TODAYS ENGINES ARE NOT VERY EFFICIENT

  36. APPROXIMATELY 15% OF THE ENERGY IN GASOLINE IS USED TO MOVE THE CAR. FRICTIONAL LOSES LOST TO COOLING LOST TO EXHAUST

  37. LET'S MOVE ON

  38. DURING COMBUSTION EXPLOSION WOULD HAVE TRANSFER THRU RADIATION TO HEAD, CYLINDER WALL, AND TOP OF PISTON ALSO TRANSFER THRU CONVECTION TO HEAD, CYLINDER WALL AND TOP OF PISTON and…. WHICH TYPE OF HEAT TRANSFER DO WE USE IN AN ENGINE?

  39. FROM INSIDE OF CYLINDER WALL AND HEAD… HEAT TRANSFER THRU CONDUCTION TO OUTSIDE OF CYLINDER WALL AND HEAD FROM OUTSIDE OF CYLINDER WALL AND HEAD… HEAT TRANSFER THRU CONVECTION TO SURROUNDING AIR ON AIR COOLED TO SURROUNDING LIQUID IN WATER JACKET ON LIQUID COOLED

  40. SO WE USE ALL TYPES OF HEAT TRANSFER TO COOL AN ENGINE

  41. LET'S MOVE ON

  42. TYPES OF COOLING SYSTEMS AIR COOLED LIQUID COOLED

  43. AIR COOLING LETS TAKE THE SIMPLE SYSTEM FIRST

  44. TYPES OF AIR COOLING WE WILL NEED THIS IN OUR NOTES FORCED DRAFT OPEN DRAFT

  45. FORCED DRAFT HAS A FAN TO FORCE AIR ACROSS ENGINE USUALLY USED ON ENGINES THAT ARE STATIONARY OR THAT AREN’T MOVED VERY FAST USES SHROUDS TO DIRECT AIR TO PROPER PLACES ALL YOUR ENGINES ARE FORCED DRAFT YOUR FLYWHEEL ACTS AS THE FAN

  46. LETS ADD THAT TO OUR ENGINE PARTS LIST PURPOSES FOR THE FLYWHEEL A.TO KEEP ENGINE MOVING THRU NON POWER STROKES B. ACTS AS A FAN FOR THE COOLING SYSTEM C. WE WILL GET D. C. AND D. LATER

  47. SHROUDS FOR FORCED DRAFT WHAT WOULD HAPPEN IF WE LEFT ONE OFF?

  48. NOTICE THE FINS. THESE ARE CALLED HEAT DISAPATING FINS. THEY ADD SURFACE AREA SO MORE HEAT CAN BE REMOVED. WHAT WOULD HAPPEN IF WE BROKE ONE OFF?

  49. TYPCIAL AIR COOLED MOTORCYCLE ENGINE LETS LOOK AT AN OPEN DRAFT AIR COOLED ENGINE HAS NO FAN ENGINE MUST MOVE THROUGH AIR FOR AIR MOVEMENT MAY OR MAY NOT HAVE SHROUDS

  50. MUST HAVE HEAT DISAPATING FINS AS WELL REMEMBER ENGINE MUST MOVE THROUGH AIR TO GET PROPER COOLING ON THE OPEN DRAFT DESIGN! WITHOUT AIR MOVEMENT, ENGINE CAN OVERHEAT. ESPECIALLY ON HOT DAYS.

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