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Re: Drinking bird

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  • mad_professor_x2000
    To Messrs Galliard, Hutchins & Cantrell, Navigating the Tesla Turbine Site as a new member led me to the exchange of messages on the drinking bird subject.
    Message 1 of 17 , Aug 1, 2002
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      To Messrs Galliard, Hutchins & Cantrell,

      Navigating the Tesla Turbine Site as a new member led me to the
      exchange of messages on the drinking bird subject.

      Well, SOMEBODY was right in stating that evaporation provides the
      temperature gradient. The water that the bird "drinks" is NOT at
      ambient temperature, due simply to this evaporation. The bird does
      not defy any physical laws.

      However, I am somewhat disappointed to find members denigrating each
      other and also a little mystified - my interest is in the Tesla
      Turbine: its design and scope of function. I wish to explore the
      possibility of building one and experimenting with it. I also have an
      avid interest in the Tesla Coil, Magnifying Transmitter, Tesla
      Receiver, the Fluidic Valve and other related paraphernalia.

      So, what on Earth has the bird to do with Tesla Turbines?

      If it is but an illustrator of thermodynamic principles (the liquid
      piston aspect seems irrelevant to me), then other turbines, such as
      axial, radial and peripheral flow types would surely be more useful.
      After all, thermodynamics is but one set of equations dealing with
      the combustion and energy conservation side if the issue. There is
      also the fluid dynamics issue to deal with and the bird's capacity to
      exemplify this strikes me as rather limited.

      Well, I will admit that I haven't perused all of the correspondence
      of these threads, so I may be missing something, but my interest in
      this site does centre on the Turbine. With that in mind, I would be
      most grateful to any of you gentlemen for some helpful directions to
      information of the kind I am after: ie; working principles &
      design/construction info.

      With thanks & regards,

      Mad Professor.
    • Boyd Cantrell
      Dear Mad professor I thought we were done with this and that is as it should be, but then you said, ... ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ You are absolutely
      Message 2 of 17 , Aug 1, 2002
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        Dear Mad professor

        I thought we were done with this and that is as it
        should be, but then you said,

        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
        > The water that the bird "drinks" is NOT at
        > ambient temperature, due simply to this evaporation.
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        You are absolutely correct, but its misleading. It will
        cause people to think the the bird runs on the difference
        between the temperature of the glass of water and the air.

        To prove that is not true, one can read the data in the files
        from Carnegi Mellon and the URL that I posted or they can
        put the bird and and glass of water out in the air and notice
        that the bird will work right now if you dunk his head and
        let that water on his head start evaporating.

        You don't have to wait untill the water in the glass becomes
        cooler. Then after a while YES, the glass of water will be
        cooler, but that is not a requirement of the operation. The
        coolness that counts is that on the birds head where the
        water is evaporating and cooling the gas inside the tube.

        I just didnt' want people to go away thinking that it works on
        the difference between the temperature of the glass of water
        and the air.
      • McGalliard, Frederick B
        Dear Mad. You should find a comment I offered about the use of the tesla turbine for low temperature difference engines in one of the previous bird posts.
        Message 3 of 17 , Aug 1, 2002
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          Dear Mad. You should find a comment I offered about the use of the tesla
          turbine for low temperature difference engines in one of the previous "bird"
          posts. This is a very interesting application area and may turn out to be
          one of great interest to the solar energy applications we will need for the
          future. Standard piston steam engines, even liquid piston engines like the
          bird, can be made to work quite well with very low temperature differences.
          The piston engine efficiency (using the thermodynamic efficiency limits as
          100%) is usually very poor due to high friction components and heat exchange
          with the walls. In very large systems a multistage turbine, at considerable
          cost, may have a very good efficiency and even come pretty close to the TD
          limits. The Tesla turbine has the very interesting features of being cheap
          to build and in a single stage it offers the features that we pay dearly for
          in the multistage standard turbine. I believe that the turbine can be
          operated in a region where it's efficiency would approach the TD limits. To
          do this it is clear that the input nozzle orifice needs to be relatively
          small, so the gas will swirl about the turbine a large number of times
          before exiting, and the blade velocity and gas velocity will be nearly the
          same. It is also clear that the blades need to have a relatively small
          center exhaust hole, but not too small, and perhaps a flow straightener to
          shift the exhaust swirl into velocity in the exhaust port direction. While
          others swear by the need for the rivets to provide start up torque, I think
          the high efficiency operation may require few such irregularities, even if
          the turbine has to be spun up by an electric motor to begin proper
          operation. The gradual extraction of energy from the gas, with a gradual
          change in temperature as it flows through the turbine, should allow the TT
          to capture most of the energy without the losses that so hamstring the
          piston type engines. If I ever get good enough at construction to make a
          pair of TTs, a compressor and turbine pair, I will examine the "gain" as a
          function of temperature differences for gas operation, similar to the
          Stirling engines operation cycle. Because of the losses this type of turbine
          may require a higher temperature to run. A system with boiling propane,
          butane, or similar low boiling point liquid can probably be run with some
          efficiency loss under a much broader set of conditions, and I have
          considered using water under vacuum conditions. These low temperature
          difference engine design considerations could be just what the doctor
          ordered for home solar power applications.

          BTB. We could construct a much larger version of drinking bird, not
          evaporation driven, probably not using gravity and gross motion of the motor
          to change states, and obtain a modestly powerful cyclic fluid flow. Now if
          we run the fluid through a TT, we would obtain direct access to this energy.
          A fluid TT of quite small size could perform very well here. I think we
          would still need some kind of valving if the flow regularly reverses. This
          would be a bit akin to the solar Stirling motor that uses a liquid piston.

          -----Original Message-----
          From: mad_professor_x2000 [mailto:mad_professor@...]
          To Messrs Galliard, Hutchins & Cantrell,

          Navigating the Tesla Turbine Site as a new member led me to the
          exchange of messages on the drinking bird subject.

          Well, SOMEBODY was right in stating that evaporation provides the
          temperature gradient. The water that the bird "drinks" is NOT at
          ambient temperature, due simply to this evaporation. The bird does
          not defy any physical laws.

          However, I am somewhat disappointed to find members denigrating each
          other and also a little mystified - my interest is in the Tesla
          Turbine: its design and scope of function. I wish to explore the
          possibility of building one and experimenting with it.
        • Mad Professor
          Hi, Boyd, You re right there, of course. What matters is the direct cooling effect on the bird s head. If the bird is oscillating, as it normally would, it
          Message 4 of 17 , Aug 3, 2002
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            Hi, Boyd,
                          You're right there, of course.
             
            What matters is the direct cooling effect on the bird's head. If the bird is oscillating, as it normally would, it will occur as a result of evaporation directly from the bird's beak, in which case, the water does not need to be below ambient, but if not, then the mechanism should rely upon the water being cooler than ambient. It's probably worth noting that the liquid contained within the bird is alcohol-based, from memory. The internal evaporation-condensation cycle is more active (in sunshine, for instance) than ordinary water would permit, so the bird is naturally more sensitive to changes in temperature and not much shift in centre of mass is actually required to make the bird oscillate.
             
            Anyway, in short, I concur and with that, let the bird rest.
             
            Regards, Prof. 
            -----Original Message-----
            From: Boyd Cantrell <bmc@...>
            To: TeslaTurbine@yahoogroups.com <TeslaTurbine@yahoogroups.com>
            Date: Friday, 2 August 2002 12:52
            Subject: Re: [TeslaTurbine] Re: Drinking bird

            Dear Mad professor

            I thought we were done with this and that is as it
            should be, but then you said,

            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
            > The water that the bird
            "drinks" is NOT at
            > ambient temperature, due simply to this
            evaporation.
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
            You are absolutely correct, but its misleading.  It will
            cause people to think the the bird runs on the difference
            between the temperature of the glass of water and the air. 

            To prove that is not true, one can read the data in the files
            from Carnegi Mellon and the URL that I posted or they can
            put the bird and and glass of water out in the air and notice
            that the bird will work right now if you dunk his head and
            let that water on his head start evaporating. 

            You don't have to wait untill the water in the glass becomes
            cooler.  Then after a while YES, the glass of water will be
            cooler, but that is not a requirement of the operation.  The
            coolness that counts is that on the birds head where the
            water is evaporating and cooling the gas inside the tube. 

            I just didnt' want people to go away thinking that it works on
            the difference between the temperature of the glass of water
            and the air.





            Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
          • Mad Professor
            Hello, Frederick, Thanks for the illuminating reply. I certainly had missed a good deal of the material exchanged by members on the bird subject and you ve now
            Message 5 of 17 , Aug 3, 2002
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              Hello, Frederick,
                                      Thanks for the illuminating reply. I certainly had missed a good deal of the material exchanged by members on the bird subject and you've now given me an excellent perspective on it.
               
              Admittedly, the liquid piston arrangement as found in the bird has possibilities I didn't at first imagine, including differentiation/separation of gas volumes by temperature, and as an engine in its own right.
               
              Thermodynamic efficiency of all engines has to be reckoned on the Kelvin Scale, not Celsius or Fahrenheit. In most small engine cases, this puts the engine between 270 & 300 degrees behind the efficiency eightball just to start,without recourse to friction losses.
               
              An obvious conventional approach is the use of a catalytic converter, which I'm sure is what you have hinted at. Raising fuel temperature in the exhausted gas stream to the point of phase conversion from liquid to gas (butane and propane do this easily and can readily afford efficinecy gains in the thermal range below ambient); but this principle can be applied perhaps as readily to heavier fuels, also. Generally, the higher the operating temperature of the engine, the better the efficiency potential.
               
              Some two decades ago, I worked in a brown coal fired power station with multi-stage turbines (steam) and am familiar with the plethora of conservation/recovery contrivances used. Most, as you say, are only practical in large systems where economies of scale can be garnered. One thing is certain - the hotter the steam, the greater the efficiency. it's analogous to high voltage AC transmission. The higher the voltage (& frequency?) the lower the loss.
               
              I am still trying to garner a better understanding of the TT and the way it works - seems to me that the turbine itself resides entirely within what I regard as the exhaust chamber, though it is probably not so simplistic or clear-cut as that. I am not yet perfectly clear on the method of achieving air induction and compression, though I have no doubt it is achieved somehow.
               
              With that in mind, I am looking for good pictures, diagrams, schematics and notes on the TT.
               
              I am pleased that several Members have been kind enough to reply to the message I posted and at least one mentions some possibly worthwhile links for me to follow up. I must also try to track that posting you mentioned on the low temperature difference engines.
               
              Another thing is now certain, from the standpoint of my perceptions on this forum. My initially disappointing impressions thankfully don't do it (or the Members) enough justice. I think I may be in very good company, here.
               
              Many thanks, Frederick. I hope to correspond with you again, perhaps soon.
               
              Regards,
                          Prof.
               
               
              -----Original Message-----
              From: McGalliard, Frederick B <frederick.b.mcgalliard@...>
              To: 'TeslaTurbine@yahoogroups.com' <TeslaTurbine@yahoogroups.com>
              Date: Friday, 2 August 2002 1:04
              Subject: RE: [TeslaTurbine] Re: Drinking bird

              Dear Mad. You should find a comment I offered about the use of the tesla
              turbine for low temperature difference engines in one of the previous "bird"
              posts. This is a very interesting application area and may turn out to be
              one of great interest to the solar energy applications we will need for the
              future. Standard piston steam engines, even liquid piston engines like the
              bird, can be made to work quite well with very low temperature differences.
              The piston engine efficiency (using the thermodynamic efficiency limits as
              100%) is usually very poor due to high friction components and heat exchange
              with the walls. In very large systems a multistage turbine, at considerable
              cost, may have a very good efficiency and even come pretty close to the TD
              limits. The Tesla turbine has the very interesting features of being cheap
              to build and in a single stage it offers the features that we pay dearly for
              in the multistage standard turbine. I believe that the turbine can be
              operated in a region where it's efficiency would approach the TD limits. To
              do this it is clear that the input nozzle orifice needs to be relatively
              small, so the gas will swirl about the turbine a large number of times
              before exiting, and the blade velocity and gas velocity will be nearly the
              same. It is also clear that the blades need to have a relatively small
              center exhaust hole, but not too small, and perhaps a flow straightener to
              shift the exhaust swirl into velocity in the exhaust port direction. While
              others swear by the need for the rivets to provide start up torque, I think
              the high efficiency operation may require few such irregularities, even if
              the turbine has to be spun up by an electric motor to begin proper
              operation. The gradual extraction of energy from the gas, with a gradual
              change in temperature as it flows through the turbine, should allow the TT
              to capture most of the energy without the losses that so hamstring the
              piston type engines. If I ever get good enough at construction to make a
              pair of TTs, a compressor and turbine pair, I will examine the "gain" as a
              function of temperature differences for gas operation, similar to the
              Stirling engines operation cycle. Because of the losses this type of turbine
              may require a higher temperature to run. A system with boiling propane,
              butane, or similar low boiling point liquid can probably be run with some
              efficiency loss under a much broader set of conditions, and I have
              considered using water under vacuum conditions. These low temperature
              difference engine design considerations could be just what the doctor
              ordered for home solar power applications.

              BTB. We could construct a much larger version of drinking bird, not
              evaporation driven, probably not using gravity and gross motion of the motor
              to change states, and obtain a modestly powerful cyclic fluid flow. Now if
              we run the fluid through a TT, we would obtain direct access to this energy.
              A fluid TT of quite small size could perform very well here. I think we
              would still need some kind of valving if the flow regularly reverses. This
              would be a bit akin to the solar Stirling motor that uses a liquid piston.

              -----Original Message-----
              From: mad_professor_x2000 [mailto:mad_professor@...]
              To Messrs Galliard, Hutchins & Cantrell,

              Navigating the Tesla Turbine Site as a new member led me to the
              exchange of messages on the drinking bird subject.

              Well, SOMEBODY was right in stating that evaporation provides the
              temperature gradient. The water that the bird "drinks" is NOT at
              ambient temperature, due simply to this evaporation. The bird does
              not defy any physical laws.

              However, I am somewhat disappointed to find members denigrating each
              other and also a little mystified - my interest is in the Tesla
              Turbine: its design and scope of function. I wish to explore the
              possibility of building one and experimenting with it.


              Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
            • fred b mcgalliard
              On the efficiency issue. As I recall, the intrinsic inefficiency of the steam power plants is due to the heat absorbed turning water to steam, and then
              Message 6 of 17 , Aug 5, 2002
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                On the efficiency issue.
                As I recall, the intrinsic inefficiency of the steam power plants is due to the heat absorbed turning water to steam, and then released on condensation. This takes the place of the compressor in a gas engine and it can put a huge load on the heat flow. Among the things you do to reduce this as a loss factor is operate at higher pressure and superheat the steam. At some point the pressure and super heat may make a gas turbine easier to design. All the boiling liquid (propane, alcohol, etc.) steam type engines suffer from the same basic problem, but for small plants this can be a positive advantage. The condensation/boiling compressor stage takes it's energy directly from the heat and not from the mechanical energy produced by the engine, so very low temperature differences can be used to run things like the bird.
                 
                While it is true that a low temp difference engine will only convert a little of the heat it uses into power, there is an awful lot of low grade heat available. With an engine designed to run at a difference of 20C you could have vast amounts of heat available and otherwise unusable. For this type of engine the final question is not the thermodynamic efficiency, but cost per KW.
                ----- Original Message -----
                Sent: Saturday, August 03, 2002 3:02 AM
                Subject: Re: [TeslaTurbine] Re: Drinking bird

                Hello, Frederick,
                                        Thanks for the illuminating reply. I certainly had missed a good deal of the material exchanged by members on the bird subject and you've now given me an excellent perspective on it.
                 
                Admittedly, the liquid piston arrangement as found in the bird has possibilities I didn't at first imagine, including differentiation/separation of gas volumes by temperature, and as an engine in its own right.
                 
                Thermodynamic efficiency of all engines has to be reckoned on the Kelvin Scale, not Celsius or Fahrenheit. In most small engine cases, this puts the engine between 270 & 300 degrees behind the efficiency eightball just to start,without recourse to friction losses.
                 
                An obvious conventional approach is the use of a catalytic converter, which I'm sure is what you have hinted at. Raising fuel temperature in the exhausted gas stream to the point of phase conversion from liquid to gas (butane and propane do this easily and can readily afford efficinecy gains in the thermal range below ambient); but this principle can be applied perhaps as readily to heavier fuels, also. Generally, the higher the operating temperature of the engine, the better the efficiency potential.
                 
                Some two decades ago, I worked in a brown coal fired power station with multi-stage turbines (steam) and am familiar with the plethora of conservation/recovery contrivances used. Most, as you say, are only practical in large systems where economies of scale can be garnered. One thing is certain - the hotter the steam, the greater the efficiency. it's analogous to high voltage AC transmission. The higher the voltage (& frequency?) the lower the loss.
                 
                I am still trying to garner a better understanding of the TT and the way it works - seems to me that the turbine itself resides entirely within what I regard as the exhaust chamber, though it is probably not so simplistic or clear-cut as that. I am not yet perfectly clear on the method of achieving air induction and compression, though I have no doubt it is achieved somehow.
                 
                With that in mind, I am looking for good pictures, diagrams, schematics and notes on the TT.
                 
                I am pleased that several Members have been kind enough to reply to the message I posted and at least one mentions some possibly worthwhile links for me to follow up. I must also try to track that posting you mentioned on the low temperature difference engines.
                 
                Another thing is now certain, from the standpoint of my perceptions on this forum. My initially disappointing impressions thankfully don't do it (or the Members) enough justice. I think I may be in very good company, here.
                 
                Many thanks, Frederick. I hope to correspond with you again, perhaps soon.
                 
                Regards,
                            Prof.
                 
                 
                -----Original Message-----
                From: McGalliard, Frederick B <frederick.b.mcgalliard@...>
                To: 'TeslaTurbine@yahoogroups.com' <TeslaTurbine@yahoogroups.com>
                Date: Friday, 2 August 2002 1:04
                Subject: RE: [TeslaTurbine] Re: Drinking bird

                Dear Mad. You should find a comment I offered about the use of the tesla
                turbine for low temperature difference engines in one of the previous "bird"
                posts. This is a very interesting application area and may turn out to be
                one of great interest to the solar energy applications we will need for the
                future. Standard piston steam engines, even liquid piston engines like the
                bird, can be made to work quite well with very low temperature differences.
                The piston engine efficiency (using the thermodynamic efficiency limits as
                100%) is usually very poor due to high friction components and heat exchange
                with the walls. In very large systems a multistage turbine, at considerable
                cost, may have a very good efficiency and even come pretty close to the TD
                limits. The Tesla turbine has the very interesting features of being cheap
                to build and in a single stage it offers the features that we pay dearly for
                in the multistage standard turbine. I believe that the turbine can be
                operated in a region where it's efficiency would approach the TD limits. To
                do this it is clear that the input nozzle orifice needs to be relatively
                small, so the gas will swirl about the turbine a large number of times
                before exiting, and the blade velocity and gas velocity will be nearly the
                same. It is also clear that the blades need to have a relatively small
                center exhaust hole, but not too small, and perhaps a flow straightener to
                shift the exhaust swirl into velocity in the exhaust port direction. While
                others swear by the need for the rivets to provide start up torque, I think
                the high efficiency operation may require few such irregularities, even if
                the turbine has to be spun up by an electric motor to begin proper
                operation. The gradual extraction of energy from the gas, with a gradual
                change in temperature as it flows through the turbine, should allow the TT
                to capture most of the energy without the losses that so hamstring the
                piston type engines. If I ever get good enough at construction to make a
                pair of TTs, a compressor and turbine pair, I will examine the "gain" as a
                function of temperature differences for gas operation, similar to the
                Stirling engines operation cycle. Because of the losses this type of turbine
                may require a higher temperature to run. A system with boiling propane,
                butane, or similar low boiling point liquid can probably be run with some
                efficiency loss under a much broader set of conditions, and I have
                considered using water under vacuum conditions. These low temperature
                difference engine design considerations could be just what the doctor
                ordered for home solar power applications.

                BTB. We could construct a much larger version of drinking bird, not
                evaporation driven, probably not using gravity and gross motion of the motor
                to change states, and obtain a modestly powerful cyclic fluid flow. Now if
                we run the fluid through a TT, we would obtain direct access to this energy.
                A fluid TT of quite small size could perform very well here. I think we
                would still need some kind of valving if the flow regularly reverses. This
                would be a bit akin to the solar Stirling motor that uses a liquid piston.

                -----Original Message-----
                From: mad_professor_x2000 [mailto:mad_professor@...]
                To Messrs Galliard, Hutchins & Cantrell,

                Navigating the Tesla Turbine Site as a new member led me to the
                exchange of messages on the drinking bird subject.

                Well, SOMEBODY was right in stating that evaporation provides the
                temperature gradient. The water that the bird "drinks" is NOT at
                ambient temperature, due simply to this evaporation. The bird does
                not defy any physical laws.

                However, I am somewhat disappointed to find members denigrating each
                other and also a little mystified - my interest is in the Tesla
                Turbine: its design and scope of function. I wish to explore the
                possibility of building one and experimenting with it.


                Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.


                Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
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