![]() |
If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
![]()
Check out the VW 1.2 liter diesel. Max torque 1800-2400 rpm.
Does that mean DIRECT drive is possible? Is that where you want to run the thing, at max torque? Does that maybe mean 61 hp can be found around 2400 rpm? Clueless but curious. Info on the engine copied below, and can be found in the link. Fun site. http://www.geocities.com/plane_diesel/index2.html Scroll down. Next on, under the Mini and Toyota Yaris. "VW Lupo 1.2-litre and 1.4 three-cylinder engine the first diesel direct injector to have not only its cylinder head but also its cylinder block in aluminum. At just 220 lbs Because of inherent design issues with a three cylinder design, Volkswagen used a balancer shaft to qwell vibrations and the result is an extremely smooth engine. Injection is via pumpe duse high-pressure unit injector elements arranged in the cylinder head and driven by the camshaft. The higher pressure permits a more efficient burn with improved performance and economy. The 1.2l TDI also utilizes a Garrett turbocharger with variable-vane turbine geometry. The 1.2-liter TDI has an output of 61hp and a maximum torque of 140 Nm (103 lb-ft) is available between 1,800 and 2,400 rpm." Montblack |
#2
|
|||
|
|||
![]() "Montblack" wrote "VW Lupo 1.2-litre and 1.4 three-cylinder engine the first diesel direct injector to have not only its cylinder head but also its cylinder block in aluminum. At just 220 lbs Because of inherent design issues with a three cylinder design, Volkswagen used a balancer shaft to qwell vibrations and the result is an extremely smooth engine. I wonder if the shaft balancer will be as smooth in an airplane, since it is driving the prop, instead of the road. It *seems* like it should be as good, but I still wonder. -- Jim in NC |
#3
|
|||
|
|||
![]()
On Fri, 14 Apr 2006 23:11:14 -0400, "Morgans"
wrote: "Montblack" wrote "VW Lupo 1.2-litre and 1.4 three-cylinder engine the first diesel direct injector to have not only its cylinder head but also its cylinder block in aluminum. At just 220 lbs Because of inherent design issues with a three cylinder design, Volkswagen used a balancer shaft to qwell vibrations and the result is an extremely smooth engine. I wonder if the shaft balancer will be as smooth in an airplane, since it is driving the prop, instead of the road. It *seems* like it should be as good, but I still wonder. should be. my experience with these balancers was in a 250cc Kawasaki single pot. most incredibly vibration free installation I've encountered. the balancers are balancing rotating mass imbalances within the engine. done properly the technique is impressive for what it achieves. Stealth Pilot |
#4
|
|||
|
|||
![]()
Look the VW Lupo 1.2 TDI article closer. On the right side of the picture of
two Lupo cars you will find a graphic presentation of torque & horsepower. The blue lines represent a standard production engine model (61 hp) and the red lines an "optimized" (tuned/chipped or whatever) 90 hp engine. Left side of the diagram you find the kW and horsepower figures, at the bottom the rpm and the right side shows the torque readings. The higher blue curve shows the hp, the lower shows the torque. Now look e.g. 2500 rpm (drehzahl 1000 U/min) at the bottom, follow the line straight up until you reach (cross) the upper blue line, then go horizontally to the left side and look the hp figure. In this example something like 48 hp. The highest torque rpm will give you the best fuel economy. That is where you would like the cruise rpm to be. In case of direct drive arrangement you get about 55 hp max by using e.g. 3000 rpm engine/prop speed. The tuned engine version does deliver about 73 hp at the same rpm. Hopefully this helps you. JP "Montblack" kirjoitti ... Check out the VW 1.2 liter diesel. Max torque 1800-2400 rpm. Does that mean DIRECT drive is possible? Is that where you want to run the thing, at max torque? Does that maybe mean 61 hp can be found around 2400 rpm? Clueless but curious. Info on the engine copied below, and can be found in the link. Fun site. http://www.geocities.com/plane_diesel/index2.html Scroll down. Next on, under the Mini and Toyota Yaris. "VW Lupo 1.2-litre and 1.4 three-cylinder engine the first diesel direct injector to have not only its cylinder head but also its cylinder block in aluminum. At just 220 lbs Because of inherent design issues with a three cylinder design, Volkswagen used a balancer shaft to qwell vibrations and the result is an extremely smooth engine. Injection is via pumpe duse high-pressure unit injector elements arranged in the cylinder head and driven by the camshaft. The higher pressure permits a more efficient burn with improved performance and economy. The 1.2l TDI also utilizes a Garrett turbocharger with variable-vane turbine geometry. The 1.2-liter TDI has an output of 61hp and a maximum torque of 140 Nm (103 lb-ft) is available between 1,800 and 2,400 rpm." Montblack |
#5
|
|||
|
|||
![]()
("JP" wrote)
[none snipped] Look the VW Lupo 1.2 TDI article closer. On the right side of the picture of two Lupo cars you will find a graphic presentation of torque & horsepower. The blue lines represent a standard production engine model (61 hp) and the red lines an "optimized" (tuned/chipped or whatever) 90 hp engine. Left side of the diagram you find the kW and horsepower figures, at the bottom the rpm and the right side shows the torque readings. The higher blue curve shows the hp, the lower shows the torque. Now look e.g. 2500 rpm (drehzahl 1000 U/min) at the bottom, follow the line straight up until you reach (cross) the upper blue line, then go horizontally to the left side and look the hp figure. In this example something like 48 hp. The highest torque rpm will give you the best fuel economy. That is where you would like the cruise rpm to be. In case of direct drive arrangement you get about 55 hp max by using e.g. 3000 rpm engine/prop speed. The tuned engine version does deliver about 73 hp at the same rpm. Hopefully this helps you. SUPER. Thanks JP! http://www.geocities.com/plane_diesel/index2.html Little green and red VW Lupos (yellow graph on right side) If you were plopping that diesel into a 750 lb. RV-3B/Sonex/whatever and you wanted to cruise 125 - 140 mph with great fuel gph rates, where would you choose to cross the graph? Both red and blue options. 1800 torque (both) 2500 rpm's (red)? 3000 rpm's (blue)? Is this in the realm of direct drive possibilities (assuming no vibration issues, etc) or does this engine NEED a PSRU to take advantage of what the engine has to offer? (Don't worry about the extra weight - if it needs one, it needs one! The plane will just have to be a single seater) How important is torque vs. rpms vs. horsepower in determining where you want to be on the graph - for engine cruise numbers? With extra low end torque available (diesel), a known size for the engine (110+ kg?), a top end cruise speed limit (140 mph), what kind of prop would you guess at? Big slow turning? Smaller for a higher revving engine? Let's say today's VW or Toyota diesels can handle some higher rpms - 3000? 4000? Thanks for helping me put the pieces together in my mind/imagination. Montblack |
#6
|
|||
|
|||
![]()
Some tough but interesting questions. I am certainly not an expect of this
particular matter, but I try to explain out the basics. There are competent experts out there, who can give you much more precise advices. Let's assume that direct drive concept is to be used. We should know, what kind of propeller to use. An electric variable pitch propeller might work well. I use the following as an example: Airmaster AP332 ( http://www.airmasterpropellers.com/w...idWebPage=3475 ). Note the maximum speed 3300 rpm. This would give an opportunity to raise the take-off engine/prop speed up to that 3300 rpm level. In VW Lupo 1.2 TDI engine case, that would mean a take-off power of about 57-58 hp (standard version) or about 82 hp tuned engine version. Of course the prop issue is more complicated in a real life and slower prop speed would produce much less noise. That 3300 rpm produces the maximum propeller tip speed allowed by the manufacturer. That is fine during a take-off, but instantly when the aircraft starts to move forward, things change a bit. If we think only the engine, it probably would run happily 3300 rpm hour after hour. That hardly is an issue. But when the velocity of the aircraft increases, the propeller tip speed will increase. That because the aircraft is now flying into a "headwind". Aircraft forward speed & propeller rotational tip speed together will produce so called propeller vector tip speed. That means, with a 3300 rpm cruise setting you are in a danger to run the blade tip speed into a supersonic region, losing efficiency and possibly destroying the prop in a very bad way! Not a way to go! That means, during the flight the rpm level has to be brought down. How much? That can be calculated by someone (a relative matter depending on cruise speed and probably also velocity never exceed). You may already know this all, but I still explain it. So during flight the rpm setting has to be lowered. Let's assume a figure like 2500 rpm (about 76% of the max 3300). The VW engine still produces about 48 hp (standard version) or about 61-62 hp (tuned version). In order to get optimum efficiency out of the powerplant, a variable pitch propeller is used in this example. By adding propeller pitch, the rpm level can be maintained in preferred range and an optimum cylinder pressure level is produced. [Note now, that it has to be mentioned, that probably all the modern car diesel engines are controlled by an ECU (electronic control unit) governing all the engine functions. It is a matter of its own to get such an engine controller to function in an aircraft]. But presented simply you could set a certain engine power level (by a throttle or actually amount of injection in this case) and let an electronic propeller pitch control unit (e.g. Airmaster AC 200: http://www.airmasterpropellers.com/w...idWebPage=3473 ) to take care of the prop rpm (e.g. that 2500). This 2500 rpm level is within the best torque range of VW 1.2 TDI engines. During a 2500 rpm cruise, the jet fuel (or light fuel oil - note there is this issue of freezing point, it's cold up there!) consumption PER HOUR might be something like 17+ pounds (2.5+ gallons) standard version, 22+ pounds (3.3+ gallons). That is just a rough estimation. Direct drive concept in this case would provide a sort of WWI or 1920's look where inline engine block is vertical and the propeller drive (power take-off) is positioned relatively low. The propeller ground clearance must to be checked carefully. So it may be feasible to have a direct drive diesel engine configuration, depending on the required power/weight/cost etc. This information presented is not accurate and please do not use it for any exact planning. Get a second opinion :-) I just present what I consider reasonable. Other people may tackle possible propeller drive vibrations and many other issues etc. JP http://www.geocities.com/plane_diesel/index2.html Little green and red VW Lupos (yellow graph on right side) If you were plopping that diesel into a 750 lb. RV-3B/Sonex/whatever and you wanted to cruise 125 - 140 mph with great fuel gph rates, where would you choose to cross the graph? Both red and blue options. 1800 torque (both) 2500 rpm's (red)? 3000 rpm's (blue)? Is this in the realm of direct drive possibilities (assuming no vibration issues, etc) or does this engine NEED a PSRU to take advantage of what the engine has to offer? (Don't worry about the extra weight - if it needs one, it needs one! The plane will just have to be a single seater) How important is torque vs. rpms vs. horsepower in determining where you want to be on the graph - for engine cruise numbers? With extra low end torque available (diesel), a known size for the engine (110+ kg?), a top end cruise speed limit (140 mph), what kind of prop would you guess at? Big slow turning? Smaller for a higher revving engine? Let's say today's VW or Toyota diesels can handle some higher rpms - 3000? 4000? Thanks for helping me put the pieces together in my mind/imagination. Montblack |
#7
|
|||
|
|||
![]()
Referring to that earlier message (below) I would like to add something.
When you look that VW Lupo 1.2 TDI engine performance diagram http://www.geocities.com/plane_diesel/index2.html Little green and red VW Lupos (yellow graph on right side) You should know (perhaps you do) that the engine performance measurement presented in such a diagram is always done by using wide open throttle (WOT). That means, it is not possible to achieve the same performance level in an aerial vehicle equipped with a fixed pitch propeller, because it is always tuned to some specific speed range. By using variable pitch propeller it is possible to get closer to the original automotive engine performance specs. When you look what I wrote earlier (below) about electronic propeller pitch control unit, there is a big gain available. Basically you could give the engine full throttle and let the electronic governor to regulate preferred rpm level. For example: http://www.airmasterpropellers.com/w...idWebPage=3473 & http://www.airmasterpropellers.com/w...idWebPage=3476 & http://www.airmasterpropellers.com/m...tion_sheet.pdf show you some information. The controller functions: take-off, climb and cruise are factory preset (rpm) settings that can be customized with a PC. Then there is this HOLD function that gives you a possibility to manually set any desired RPM during flight and hold that setting. As said, basically you could just use full engine power setting and let the governor do its work (maintain the set rpms, e.g. 2500) . This provides efficient engine performance. There are some concerns still. There should be some kind of warning indicator or actuator in case of engine over-rev situation = over 3300 rpm in this example (possible if the prop or controller fails). The second matter is, that despite of all this (naturally) you yourself are the regulator of airspeed, by manipulating throttle setting. It is of course possible to violate aircraft structural speed limitations in some situations. JP "JP" kirjoitti ... Some tough but interesting questions. I am certainly not an expect of this particular matter, but I try to explain out the basics. There are competent experts out there, who can give you much more precise advices. Let's assume that direct drive concept is to be used. We should know, what kind of propeller to use. An electric variable pitch propeller might work well. I use the following as an example: Airmaster AP332 ( http://www.airmasterpropellers.com/w...idWebPage=3475 ). Note the maximum speed 3300 rpm. This would give an opportunity to raise the take-off engine/prop speed up to that 3300 rpm level. In VW Lupo 1.2 TDI engine case, that would mean a take-off power of about 57-58 hp (standard version) or about 82 hp tuned engine version. Of course the prop issue is more complicated in a real life and slower prop speed would produce much less noise. That 3300 rpm produces the maximum propeller tip speed allowed by the manufacturer. That is fine during a take-off, but instantly when the aircraft starts to move forward, things change a bit. If we think only the engine, it probably would run happily 3300 rpm hour after hour. That hardly is an issue. But when the velocity of the aircraft increases, the propeller tip speed will increase. That because the aircraft is now flying into a "headwind". Aircraft forward speed & propeller rotational tip speed together will produce so called propeller vector tip speed. That means, with a 3300 rpm cruise setting you are in a danger to run the blade tip speed into a supersonic region, losing efficiency and possibly destroying the prop in a very bad way! Not a way to go! That means, during the flight the rpm level has to be brought down. How much? That can be calculated by someone (a relative matter depending on cruise speed and probably also velocity never exceed). You may already know this all, but I still explain it. So during flight the rpm setting has to be lowered. Let's assume a figure like 2500 rpm (about 76% of the max 3300). The VW engine still produces about 48 hp (standard version) or about 61-62 hp (tuned version). In order to get optimum efficiency out of the powerplant, a variable pitch propeller is used in this example. By adding propeller pitch, the rpm level can be maintained in preferred range and an optimum cylinder pressure level is produced. [Note now, that it has to be mentioned, that probably all the modern car diesel engines are controlled by an ECU (electronic control unit) governing all the engine functions. It is a matter of its own to get such an engine controller to function in an aircraft]. But presented simply you could set a certain engine power level (by a throttle or actually amount of injection in this case) and let an electronic propeller pitch control unit (e.g. Airmaster AC 200: http://www.airmasterpropellers.com/w...idWebPage=3473 ) to take care of the prop rpm (e.g. that 2500). This 2500 rpm level is within the best torque range of VW 1.2 TDI engines. During a 2500 rpm cruise, the jet fuel (or light fuel oil - note there is this issue of freezing point, it's cold up there!) consumption PER HOUR might be something like 17+ pounds (2.5+ gallons) standard version, 22+ pounds (3.3+ gallons). That is just a rough estimation. Direct drive concept in this case would provide a sort of WWI or 1920's look where inline engine block is vertical and the propeller drive (power take-off) is positioned relatively low. The propeller ground clearance must to be checked carefully. So it may be feasible to have a direct drive diesel engine configuration, depending on the required power/weight/cost etc. This information presented is not accurate and please do not use it for any exact planning. Get a second opinion :-) I just present what I consider reasonable. Other people may tackle possible propeller drive vibrations and many other issues etc. JP http://www.geocities.com/plane_diesel/index2.html Little green and red VW Lupos (yellow graph on right side) If you were plopping that diesel into a 750 lb. RV-3B/Sonex/whatever and you wanted to cruise 125 - 140 mph with great fuel gph rates, where would you choose to cross the graph? Both red and blue options. 1800 torque (both) 2500 rpm's (red)? 3000 rpm's (blue)? Is this in the realm of direct drive possibilities (assuming no vibration issues, etc) or does this engine NEED a PSRU to take advantage of what the engine has to offer? (Don't worry about the extra weight - if it needs one, it needs one! The plane will just have to be a single seater) How important is torque vs. rpms vs. horsepower in determining where you want to be on the graph - for engine cruise numbers? With extra low end torque available (diesel), a known size for the engine (110+ kg?), a top end cruise speed limit (140 mph), what kind of prop would you guess at? Big slow turning? Smaller for a higher revving engine? Let's say today's VW or Toyota diesels can handle some higher rpms - 3000? 4000? Thanks for helping me put the pieces together in my mind/imagination. Montblack |
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
2-stroke diesel is the (near) future? | Max Kallio | Home Built | 134 | July 18th 05 12:39 AM |
2-stroke diesel is the (near) future? | Max Kallio | Rotorcraft | 123 | July 18th 05 12:39 AM |
Diesel Jodel information..........and .........diesel plane groups | Roland M | Home Built | 1 | January 4th 04 04:04 AM |
Diesel Jodel information..........and .........diesel plane groups | Roland M | Owning | 1 | January 4th 04 04:04 AM |
Diesel engines for Planes Yahoo Group Jodel Diesel is Isuzu Citroen Peugeot | Roland M | Rotorcraft | 2 | September 13th 03 12:44 AM |