Re: Rotary valved engines
Posted: Sun Sep 15, 2013 10:17 pm
I have been interested in these designs for a lot of years and they have all been experimented with, but each found lacking in some areas, so no one has actually taken up the challenge of developing them fully.
The Wankel rotary engine ( which more or less brought NSU to it's knees) being a prime example was rushed into production before development was properly finished and because the problems of rotor sealing and wear on the trochoidal bore were not overcome, it quickly brought home to NSU that it is extremely unwise to dive head first into something so radical, however good it seems to be.
Mazda have persevered with development of the Wankel and have made great strides ever since but only with partial success. Wisely they did not forsake the good old piston engine technology - that must tell us something!
The Coates system does look good, although the unlubricated seal technology would still need to be proven in everyday use,- I'm sure that it will work well, but for how long?
In order to get the well established engine manufacturers to forsake their extremely reliable, profitable and well proven existing poppet valve engines for this layout would be nothing short of a miracle!
Very often, new ideas are resolved only under the pressure of wartime needs, an example would be the successful sleeve valve engines developed and perfected by Napier and Bristol in England, - by the end of WW2, they were second to none in reliability, quietness and fuel consumption but all this was unfortunately brushed aside when the turbine engines took over.
The Coates engine has been around for a while and obviously is not being snapped up for the reasons I mention above, this does not mean that it it isn't any good, but there may be other developments about to happen (like electric and hybrid vechiles) and even the use of turbine engines driving generators, although kerosene burning vehicles on the roads would create horrendous smelling fumes,(ie.if the smells you sometimes get through the ventilation systems in airliners when taxying is anything to go by)!
This I admit is getting away from the original posting, but I think these things do need some thought.
However, it doesn't need to stop someone from creating a model from some of these ideas simply for the pleasure of doing so!
The Wankel rotary engine ( which more or less brought NSU to it's knees) being a prime example was rushed into production before development was properly finished and because the problems of rotor sealing and wear on the trochoidal bore were not overcome, it quickly brought home to NSU that it is extremely unwise to dive head first into something so radical, however good it seems to be.
Mazda have persevered with development of the Wankel and have made great strides ever since but only with partial success. Wisely they did not forsake the good old piston engine technology - that must tell us something!
The Coates system does look good, although the unlubricated seal technology would still need to be proven in everyday use,- I'm sure that it will work well, but for how long?
In order to get the well established engine manufacturers to forsake their extremely reliable, profitable and well proven existing poppet valve engines for this layout would be nothing short of a miracle!
Very often, new ideas are resolved only under the pressure of wartime needs, an example would be the successful sleeve valve engines developed and perfected by Napier and Bristol in England, - by the end of WW2, they were second to none in reliability, quietness and fuel consumption but all this was unfortunately brushed aside when the turbine engines took over.
The Coates engine has been around for a while and obviously is not being snapped up for the reasons I mention above, this does not mean that it it isn't any good, but there may be other developments about to happen (like electric and hybrid vechiles) and even the use of turbine engines driving generators, although kerosene burning vehicles on the roads would create horrendous smelling fumes,(ie.if the smells you sometimes get through the ventilation systems in airliners when taxying is anything to go by)!
This I admit is getting away from the original posting, but I think these things do need some thought.
However, it doesn't need to stop someone from creating a model from some of these ideas simply for the pleasure of doing so!