Diesel, the Modern Power

[Music] today we take fire as a matter of course it lights our cigarettes cooks our food warms our homes serves industry and performs a thousand other vital tests and starting a fire nowadays is a simple matter to us it's no problem at all to the men of ancient times however the art of making fire was as important and as difficult as life itself one method was to strike together two stones one a flint the other containing iron in some form another method produced fire by rubbing two pieces of wood one against the other while the people of southeastern Asia many years ago learned to make fire by compressed air using an extraordinary contrivance known as the fire piston or fire syringe this consisted of a hollow tube closed at one end and a round stick which could be inserted into the top of the tube tinder was placed usually at the bottom of the round stick then when this stick or plunger was driven down quickly the tinder took fire and burned repeating this action slow down let's see what happens inside this fire making apparatus as the round sticker plunger moves down the tube the air in the tube is trapped confined to a smaller and smaller space and finally the tinder at the end of the plunger ignites result fire through compression but why to find the answer to this question let's construct a modern fire syringe turn the apparatus upside down and put a couple of thermometers in convenient places these thermometers will record the room temperature and the other will register the temperature of the air inside the cylinder next we add an instrument for measuring the air pressure inside the cylinder and now we transform the primitive fire-making device into a modern scientific apparatus the pressure gauge reads 0 and both thermometers are at room for a chore 74° now we start compressing the air as the piston goes up the pressure rises the temperature outside of the cylinder remains the same but inside the cylinder the more the air is compressed the higher the top enough to boil water higher and higher go temperature and pressure now it's hot enough to melt tin until finally the air in the cylinder is compressed into about 1/16 of the space it occupied before we started compressing it at this point the pressure and the temperature of the air inside the cylinder are extremely high and if a mist of oil could be sprayed into it here's what would happen now let us repeat this action in slow motion oil is sprayed into the cylinder it catches fire and burns temperature and pressure increase driving the piston downward and so we've seen demonstrated a basic scientific principle the fact that when air is compressed it gets hot now let's pause to examine another basic scientific principle one which is best understood through an experiment a piece of rubber sheeting is stretched over the mouth of a glass container the glass is heated and the rubber sheeting puffs out like a balloon this is because air expands when it is heated so now let's apply this second principle first the air in the cylinder becomes hot from compression then it's heated to a much higher temperature by the burning oil increasing the pressure so it pushes the piston down now let's convert this apparatus into a mechanism which will apply these two scientific principles in such a way as to provide useful energy first let's take away the pressure gauge and the thermometers and strengthen the walls of the cylinder to withstand continued high temperatures and pressures now we'll need a couple of pipes or manifolds one to bring fresh air into the cylinder and the other to carry the burden gasses out of it also a couple of valves to Cork the air in the cylinder while it's being compressed and while the oil burns next we install a better atomizer which we will call the injector unit then in order to transform the up-and-down motion of our piston into more convenient turning motion we replace the piston rod with a crankshaft and connecting rod but one thing more is needed something which will keep speed uniform between powered impulses so we add a heavy flywheel and to protect and support our apparatus we add a housing and a base now let's see how this mechanism works first the intake valve opens and as the piston moves downward fresh air is drawn into the cylinder now the intake valve closes tightly caulking the air in the cylinder and we drive the piston upward on its compression stroke the injector unit sprays fuel oil into the top of the cylinder the oil burns pushing the piston down now the exhaust valve opens the piston moves up and the gases are resulting from the burned oil are forced out this is called a four stroke or four cycle diesel engine because it has four strokes to each cycle exhaust intake compression power exhaust intake compression power exhaust one of the most interesting and important parts of our engine is the atomizer or injector unit let's see why the diesel engine operates on a compression ratio of 16 to 1 as we've seen this means that the air inside of the suit is compressed into 1/16 of the space it normally required building up a pressure of 500 to 600 pounds per square inch against this tremendous pressure the injector unit must drive fuel into the cylinder with such force that it spreads almost instantaneously to all parts of the combustion chamber here's how the injector unit works first of all it's made up of a pump an injection valve and the injector nozzle the injector pump presses down on the oil until it reaches a pressure or from 15 to 20 thousand pounds per square inch allowing a small quantity of oil to pass through the injector nozzle into the cylinder the fuel must burn quickly so it's pushed into the cylinder through tiny holes in the injector nozzle which are no bigger than the diameter of a small needle these break it up into a fine fog or spray and so efficient is this remarkable mechanism that it forces oil through the highly compressed air in the cylinder at a rate of over 600 miles per hour that's almost twice as fast as the fastest racing cars and even faster than the fastest airplanes the injector unit also controls a speed of the diesel engine the more fuel oil sprayed into the cylinder the greater its speed and the amount of fuel entering the cylinder is varied by a sliding bar which is connected to the throttle of the engine this bar engages a gear which is attached to the plunger of the injector pump so that when the bar is moved back and forth the pump plunger turns and so the turning action of the plunger increases or decreases the effective stroke of the pump thus varying the amount of fuel entering the cylinder in other words the injector unit is called upon to do a big job in a very small amount of space and time it's able to do that job only because of the amazing precision with which it's fitted together and every unit must pass this exacting test or the machine which checks accuracy to millionths of an inch to illustrate the precision required in the manufacture of the injector unit let us place a human hair under a microscope now suppose that hair were split into about 125 equal parts one 125th of that hair is equal to the clearance between the plunger and the barrel of the injector unit pump this remarkable device was the result of the activities of many scientists and engineers working to solve the problem are properly injecting the fuel into the cylinders it's made up of many finally machine parts turn from the best steel available by a highly skilled workman the injector unit must not fail it's indeed the heart of the diesel engine and it was pump oil into the cylinder many thousands of times during each hour of operation and to successfully perform this job it must be as nearly perfect as it can be made the first Diesel's had only one cylinder but it was found that one cylinder diesel engines could not provide sufficient power for most operations so more cylinders were added there were two cylinder engines three cylinder four cylinder six cylinder engines engines with eight and even 12 cylinders for many purposes the four-stroke or four cycle diesel engine was the most efficient and the most economical engine in existence but the great weight and size of the engine was not needed for the intake and exhaust strokes yet the engine spent half its time merely pumping air in and out of the cylinders how could they eliminate the pump strokes that was the problem the engineers set out to solve and research and experiment resulted in the development of a pump or blower to take the place of those two pump strokes this innovation called for an important change in the engine for now it was necessary to move the intake manifold down so it encircled the base of the cylinder and fresh air was forced in by the blower through a number of openings in the cylinder wall the intake opening in the top of the cylinder was no longer needed so during the fraction of a second that the piston was at the bottom of its stroke the new pump or blower forced clean air in at the bottom of the cylinder and the clean air rushing in forced the burn gases out through the exhaust valve at the top of the cylinder so that every time the piston went up it compressed air and every time it went down it provided power our engine had become a two-stroke or two cycle diesel engine compression power compression power and so the two-stroke diesel engine furnished almost twice as much power as a four-stroke diesel engine the same size because it had twice as many power strokes and now let's have a look at the pump or blower which has made our two cycle diesel possible the two rapidly turning rotors of the blower which are now seen in slow-motion trapped the air between themselves and the wall of the blower forcing the air through into the cylinder it was found that for greatest efficiency the rotors should be curved in this unusual fashion but machining the rotors in this way presented a problem because every inch of the sighs surface of the rotors had to fit exactly to the blower walls these problems were solved however and as a result the two cycle or two-stroke diesel engine became an accomplished fact this new engine was smaller it weighed less per horsepower the four cycle engine was still extremely valuable for certain types of installations but where more power per pound of engine weight was needed the new two cycle diesel promised great things and so testing an experiment continued the engine was further perfected until in 1933 research engineers were ready to show the new diesel to the public at the Century of Progress exposition in Chicago - 600 horsepower - cycle diesels were placed on display they created wide interests and to technical Minds demonstrated that this new to cycle diesel not only operated with unprecedented economy but was reliable as well and then in 1934 came proof of performance [Applause] she's the latest thing in trains diesel powered and streamlined from end to end they're getting ready to try her out from Denver to Chicago and now she's off quickly she picks up speed 70 80 90 miles an hour on their way to shatter almost every railroad record in existence for its Denver to Chicago in 13 hours and five minutes introducing a new chapter in the history of transportation but that was only the beginning a few months later the two cycle diesel again made news and more news [Music] she's brand-new just out of the shop and this time it's going to be coast to coast from Los Angeles to New York and she'll try for a new transcontinental record into the night piloted by men who know the road and behind them there's a new kind of power modern power from a two-cycle diesel engine through the night and finally through the mists and fogs of early morning and then into the dawn over rivers and streams following that long shiny ribbon of tractors and now our cameraman takes to the air as the streamliner speeds across the plains of the Midwest this new train is like complete with all its cars it weighs less than a single steam locomotive but it hugs the tracks and it zips along smoothly and steadily the line is cleared miles ahead for this new king of the rail the speedometer reads 90 miles an hour and our cameraman climbs down between the tracks to prove this streamliner is streamlined from every angle and then New York coast to coast in 56 hours and 55 minutes a new trends pattern ëtil record with a new kind of power two cycle diesel power this new kind of power took hold of the public's fancy more and more people wanted to ride in these new diesel stream liners and so two years later public demand brought action railroad locomotives for streamlined train and here's where they're made at LaGrange Illinois General Motors built this plant where they make locomotives of the latest type and design here they're putting the finishing touches on the power plant for a modern streamlined train for these are a new kind of locomotive they're light and fast and powerful and they're sleek and streamlined pleasing to the eye they offer a minimum of resistance to the air giant crane set down the stainless steel body of this big engine on its trucks and soon she'll be ready to go ready to carry thousands of passengers quickly comfortably safely meanwhile in the General Motors styling section experts in streamlining and modern design cooperated long experience in building automobiles to please the public I aided these stylists in helping to create trains as beautiful as they were different stainless steel exterior is designed for speed and I appeal modern interiors designed for comfort and restfulness lounge cars with deep easy chairs indirect lighting and beautiful lines throughout like some exquisitely appointed modern salon but the demand for the new to cycle diesel was not limited to streamline trains in April 1937 not the announcement by General Motors of the formation of a diesel engine division and the construction of a big new plan to produce diesels for small power installations for trucks or buses and the light and meanwhile the Winton engine corporation in Cleveland a subsidiary of General Motors continued to lead the field in the production of all types of diesels here as in other General Motors diesel plants the need for more Diesel's has brought with it a need for more and more men to build them and so the diesel of today has brought employment to supply the ever-increasing demand for this modern power but the diesel engine is only just beginning to come into its own and it's full speed ahead for progress as thousands of Winton Diesel's provide power for Coast Guard cutters tugboats cruisers yachts power on the sea as well as on land modern power so much for the diesels of today and now for the future here's more news [Music] I would like to point out that the new diesel engines which we are making today are entirely different from those of the past it is therefore extremely difficult to use the experience with these older engines to predict the future the fact I think it's rather foolish to try to say anything about the future anyhow prediction is all right for Romance Writers that's terribly bad for practically engineers great many of us can remember when the telephone was quiet a new invention it was a marvel one was only five years old but it was absolutely impossible for anybody at that time to predict the marvelous worldwide service which we have today and anybody who took a ride in one of our early single-cylinder automobiles could not possibly have predicted our modern high speed and luxurious vehicle there's one question which we are asked almost every day what am I going to get a diesel engine in my automobile well we can't tell you that because there are quite a number of problems yet which have to be solved these are things which take time and there are more questions of time development than of technicality however I can say this one thing positively that you are getting everything that we have today that is worthwhile using and that we are not holding out anything on you whatever thank you mr. Kettering and so this modern two cycle diesel engine is still in its swaddling clothes but in diesel laboratories engineers and scientists labor on to find increasingly better fuels to reduce the weight of the engine and increase its power to improve the injector unit to bring you more power at less cost to bring you faster cheaper transportation through diesel the modern power [Music]