Vid presskonferensen efter Stefan Löfvens möte med talmannen yttrade Löfven ordet "självfallet" eller "självfallet, ja" ca 37 gånger. Man kan nu som väljare och medborgare i vårt lilla land ställa sig frågan om hur det kan vara så att i den synnerligen oklara, komplicerade och minst av allt självklara situation som vårt lilla land nu hamnat i, vår blivande nye statsminister väljer att komplettera nästan varje yttrande med ett emfatiskt: "Självfallet, Jaa!"
Misstanken inställer sig att det handlar om en form av magiskt tänkande: Genom att beskriva någonting de facto ingalunda självklart och i praktiken olösligt, med "självfallet, ja", så kommer allt att lösa sig till det bästa. Självfallet är det så.
fredag 26 september 2014
måndag 15 september 2014
Matematisk Analys av Valet 2014
Valet 2014 kan sammanfattas sålunda:
- Moderaterna tappar 7% till SD, vilket gör att Alliansen förlorar makten och kollapsar.
- De rödgröna (S+MP+V) med samma katastrofala resultat som 2010 skall nu styra landet med Jimmie som tung vågmästare/spelare.
- Första prioritet enligt vad Löven utlovat kommer då att bli jakten på koldioxid med målet att reducera utsläppen med 90% samtidigt som kärnkraften avvecklas.
torsdag 11 september 2014
UN Declares Successful Control of Ozon Layer: Climate Next!
Washington Post happily reports that the Earth’s ozone layer is recovering:
- The atmospheric layer that protects Earth’s inhabitants from the sun’s harmful ultraviolet rays is slowly rebuilding itself, according to a United Nations report published Wednesday.
- Scientists credit the recovery to the phasing out of chemicals used in refrigerators, air conditioners and aerosol cans in the 1980s, ... through the Montreal Protocol,
- “It’s a victory for diplomacy and for science and for the fact that we were able to work together,” said chemist Mario Molina, who won a Nobel Prize for his research into the ozone layer.
To UN this gives undisputable evidence that UN is capable of controling global climate by suitable protocols. After the observed declared undisputable success with the Montreal Protocol, the UN focus for world leaders now shifts to the Kyoto Protocol: And yes, the observed "hiatus" with no global warming over the last 18 years, gives similar strong evidence that UN is capable of controling not only the ozon layer, but also global temperatures. The fact that the hiatus is achieved with only a minor effect from the Kyoto Protocol, effectively followed only by Sweden, shows its undisputable operational power. The only trouble is an apparent conflict between the Montreal and Kyoto protocols:
- Paradoxically, the heat-trapping greenhouse gases believed to contribute to global warming are actually helping rebuild the ozone layer. Paul A. Newman, who co-chairs the U.N. panel, told the AP higher levels of carbon dioxide and other gases help cool the upper stratosphere, which increases the amount of ozone.
Large scale climate engineering thus has its difficulties, like any strong medication possibly curing one disease while killing the patient by a side-effect. We can only hope that UN is not capable of controling any aspect of global climate, by any UN protocol. There is reason to be hopeful...
måndag 8 september 2014
Stefan Löfven Lovar Minska CO2 Utsläpp med 90%
Stefan Löfven gav i valduellen i går följande besked till det svenska folket beträffande den kommande socialdemokratiska regeringens klimatpolitik:
- Vi sätter ett tufft mål: 2050 skall vi ha minskat utsläppen med 90% och så sätter vi delmål för 2040, 2030...och så gör vi det på transportsektorn, i produktionen och i boendesektorn.
- Sen ser vi till att agera därefter.
- Jag säger inte att det inte går att köra bil i framtiden....men vi måste köra på bränslen som inte släpper ut CO2.
- Kärnkraften skall avvecklas...men inte på ett sådant sätt att vi äventyrar våra jobb och vår industri...vi skall se till att ha säker tillgång till energi till konkurrenskraftiga priser...vi har inga planer på att stänga kärnkraftverk, nej, men det kommer inte att bli några nya investeringar i kärnkraft...och det skall vara CO2-snålt...detta är mina ingångsvärden...
Bäva månde det svenska folket inför denna framtid...Och varför stod Lövfen på en liten orange pall under duellen? Vem hade ställt dit den och vad betydde färgen, för att inte tala om höjden på pallen?
Kejsar Haile Selassie medförde enligt Kapuscinski ett stor mängd kuddar av olika format på sina resor för att kunna lyftas till lämplig höjd vid sina möten med världens ledare. Har Stefan Löfven förberett sitt trontillträde med en uppsättning pallar av olika höjd för olika möten?
tisdag 26 augusti 2014
KVA Omprövar Klimatuttalande: Koldioxidalarmism Saknar Vetenskaplig Grund
Så är den till slut på gång, den av många efterfrågade revisionen av KVAs klimatuttalande från 2009, som utgick från IPCC. Wibjörn Karlen anger utgångspunkten för KVAs nya uttalande värdigt en vetenskaplig akademi, denna gång grundat på vetenskap istället för politik:
- Förekomsten av växthusgaser i atmosfären, främst vattenånga, bidrar till att en rimlig temperatur råder vid jordytan. Andra gaser som koldioxid, metan och klorfluorkarbonater vars förekomst påverkas av människans aktivitet, betraktas också som växthusgaser men omfattningen av deras inverkan på klimatet är osäker.
- Koncentrationen av CO2 i atmosfären kommer att öka. I vad mån denna ökning kommer att påverka klimatet är inte känt. Trots den ökade koncentrationen av CO2 i atmosfären under de senaste arton åren har inte den global temperatur stigit. Effekten av andra växthusgaser är inte väl känd.
- Att dra långtgående slutsatser om trender i klimatet på grundval av data från några 10-tal till ett 100-tal år kan leda till dyra och meningslösa åtgärder.
Lennart Bengtsson som skrev uttalandet från 2009 har under senare år ändrat ståndpunkt till att vara uttalad skeptiker till den koldoxidalarmism som predikas av av det politiska organet IPCC. LB torde instämma i WKs ovanstående beskrivning av den vetenskapliga grunden för IPCCs koldoxidalarmism: Någon sådan vetenskaplig grund finns inte.
När väl KVA senare i höst satt detta på pränt kommer den svenska klimatpolitiken att skrivas om. Notera att LB och WK är Sveriges mest meriterade klimatvetenskapsmän och borde vara de som svenska politiker och svenska folket lyssnar på, istället för tungomålstalande gröna aktivister.
Etiketter:
KVA,
Royal Swedish Academy of Sciences
fredag 22 augusti 2014
Om Vetenskaplig Medalj, Klimat och KTH
Pehr Björnbom ger mig idag en upprättelse på Klimatupplysningen med utgångspunkt från den Prandtl-medalj som blivit mig tilldelad (som jag dock tackat nej till av skäl som framgår av tidigare poster), och ger också perspektiv på mitt öde på KTH.
Tack Pehr för detta erkännande av Dig som självständigt tänkande vetenskapsman. Hoppas vi kan fortsätta vårt utbyte av tankar om (klimat)vetenskapens mysterier, och begripligheter.
Tack Pehr för detta erkännande av Dig som självständigt tänkande vetenskapsman. Hoppas vi kan fortsätta vårt utbyte av tankar om (klimat)vetenskapens mysterier, och begripligheter.
torsdag 24 juli 2014
Response from ECCOMAS General Assembly
Here is the response to my letter to the General Assembly of ECCOMAS recorded in the previous post:
Dear Professor Johnson,
your email of July 21, 2014, was discussed in the ECCOMAS General Assembly meeting on July 22, 2014. The members of the General Assembly unanimously arrived at the following conclusions:
Ekkehard Ramm, Ferdinando Auricchio, Pedro Diez, and Josef Eberhardsteiner
President, Vicepresidents, and Secretary of ECCOMAS
Dear Professor Johnson,
your email of July 21, 2014, was discussed in the ECCOMAS General Assembly meeting on July 22, 2014. The members of the General Assembly unanimously arrived at the following conclusions:
- The selection procedure followed the official dedication of the ECCOMAS Ludwig Prandtl Medal, acknowledging your outstanding and sustained contributions in the area of computational fluid dynamics.
- It was confirmed that the award ceremony had to follow the established procedure consisting of a short introduction of the awardees and a brief summary of their major scientific achievements, not providing the possibility for addresses by the awardees. The award ceremony on Monday, July 21, 2014, executed by the organizers of the joint WCCM-ECCM-ECFD conference, exactly followed these rules.
- The ECCOMAS General Assembly regrets your decision not to accept the award of the Ludwig Prandtl Medal. However, it respects your decision.
- The ECCOMAS General Assembly considers the discussion on this matter as finished.
Ekkehard Ramm, Ferdinando Auricchio, Pedro Diez, and Josef Eberhardsteiner
President, Vicepresidents, and Secretary of ECCOMAS
Here is my comment on this conclusion of the General Assembly "unanimously arrived at":
My condition for accepting the Medal was that a very short statement authored by me was voiced at the award ceremony, by me or the chairman or the person presenting my work. What I wanted to express was that I through my work have found that Prandtl's boundary layer theory is not in accordance with observations. In short, that my work was not in agreement with Prandtl's.
This could not be accepted by the Organizers, who demanded me to either give up my condition of voicing my statement or not accept the Medal.
When presenting my decision to not accept the Medal at the award ceremony, the Organizers stated according to reports that the reason I could not accept the Medal was that the findings of my research was in opposition to Prandtl's boundary layer theory.
This was not the true reason, which was that my voice was suppressed. I had said that I can accept the Medal if my view on Prandtl's boundary layer theory is not suppressed.
This was not the true reason, which was that my voice was suppressed. I had said that I can accept the Medal if my view on Prandtl's boundary layer theory is not suppressed.
In any case, the Organizers de facto made the very statement at the award ceremony, which could not be made, namely that my view is in opposition to Prandtl's. Nothing was thus gained by forcing me to not accept the Medal.
And No, the discussion on "this matter" is not all "finished". We are only at the beginning of a long discussion to come in the world of CFD, then outside the body of ECCOMAS, where the focus can continue to be to "exactly follow established procedures" for "acknowledging outstanding and sustained contributions in the area of CFD".
There must be members of ECCOMAS, and others, who do not applaud the handling of the 2014 Prandtl Medal. To suppress expression of scientific theory and observation is to violate the most basic principle of science of free expression. It is nothing for ECCOMAS to be proud of.
If the General Assembly respects my decision to not accept the Medal, I do not respect the decision by the Organizers to force me to do so.
PS By "outstanding contributions to CFD" is apparently meant my work in the 1980s and 1990s, "sustained constributions" must then refer to my work in the 2000s and 2010s, which is exactly the work in opposition to Prandtl which could not be mentioned at the award ceremony: In mathematics, one contradiction can give rise to any number of contradictions.
If the General Assembly respects my decision to not accept the Medal, I do not respect the decision by the Organizers to force me to do so.
PS By "outstanding contributions to CFD" is apparently meant my work in the 1980s and 1990s, "sustained constributions" must then refer to my work in the 2000s and 2010s, which is exactly the work in opposition to Prandtl which could not be mentioned at the award ceremony: In mathematics, one contradiction can give rise to any number of contradictions.
måndag 21 juli 2014
Letter to the General Assembly of ECCOMAS
I want to direct the attention of the General Assembly to the following actions taken by a group of representatives of ECCOMAS in connection to the Prandtl Medal, which was to be awarded to me at the opening ceremony of the IACM-ECCOMAS Conference July 21-25 in Barcelona:
1. I was informed that I had to arrange and pay travel and accomodation myself.
2. I was not invited to the Conference Banquet and informed that the cost was not covered by ECCOMAS.
3. I was not given a fair possibility of expressing my views: No very short statement authored by me was permitted to be voiced at the award ceremony. After a long hazzle I was given a last empty slot in one of 49 parallel sessions in a room of 34 m2 accomodating at most 20 people.
4. The abstract of my talk and link to a related post on my professional blog was not put up on the conference web page, despite repeated requests by me.
5. I was met by an unfriendly uncivilized attitude in a long correspondence recorded on my blog:
3. I was not given a fair possibility of expressing my views: No very short statement authored by me was permitted to be voiced at the award ceremony. After a long hazzle I was given a last empty slot in one of 49 parallel sessions in a room of 34 m2 accomodating at most 20 people.
4. The abstract of my talk and link to a related post on my professional blog was not put up on the conference web page, despite repeated requests by me.
5. I was met by an unfriendly uncivilized attitude in a long correspondence recorded on my blog:
with related posts here, here, here and here.
As a consequence of mainly 3. I could not accept to receive the Medal.
As a consequence of mainly 3. I could not accept to receive the Medal.
I ask the General Assembly to study the details of this story, which to me has been a completely unexpected and unprecedented harrassment.
I expect the General Assembly to report back to me and in particular inform me if the reception I have met as Medalist is the normal standard of ECCOMAS.
Sincerely,
Claes Johnson
PS Letter to the Organizers asking for reimbursement of my expenses created by the Prandtl Medal Award:
To the Organizers IACM-ECCOMAS Barcelona 2014
The effect of the letter will be reported in upcoming post. Apparently, ECCOMAS has already refused to pay the hotel bill, since the cost has been drawn on my credit card. The chance that the flight ticket will reimbursed appears to be small, since my request has not even been acknowledged.
I really wonder if this is the standard of ECCOMAS, or if I am getting a special reception, because of my "outstanding and sustained contributions to CFD"? If so, it adds to my experience that the better results you may have, the more "outstanding and sustained contributions" you have created, the more opposition and suppression you will meet.
PS Letter to the Organizers asking for reimbursement of my expenses created by the Prandtl Medal Award:
To the Organizers IACM-ECCOMAS Barcelona 2014
I ask you to reimburse me for the following costs in connection to the Prandtl Medal 2014 awarded to me, which have been drawn on my personal bank account:
Hotel Rey Juan Carlos, two nights: SEK 2897
Flight Vueling EBRC7K: SEK 2211
Total SEK: 5108 (around €600)
Please send the remimbursement to Handelsbanken Strandvägen 5B, Box 14222, 104 40 Stockholm
Clearingnumber: 6124, Swift/BIC: HANDSESS
account xxxxxxxxx
Please inform me ASAP when the payment has been done, or if you for some reason are unable to make the transaction.
Sincerely,
Claes Johnson
I really wonder if this is the standard of ECCOMAS, or if I am getting a special reception, because of my "outstanding and sustained contributions to CFD"? If so, it adds to my experience that the better results you may have, the more "outstanding and sustained contributions" you have created, the more opposition and suppression you will meet.
söndag 20 juli 2014
The End of the Prandtl Medal
Here is the last exchange of emails concerning the Prandtl Medal between me and representatives for ECCOMAS offering the Medal to me and IACM co-organizing the conference at which opening ceremony tomorrow the Medal would have been hanged around my neck.
the sole intention of ECCOMAS to select you as the awardee of the 2014 Ludwig Prandtl Medal was to acknowledge your outstanding and sustained contribution in the field of Computational Fluid Dynamics.
The correspondence (full account in previous post) shows that the contradiction of giving the Prandtl Medal to me was resolved into one of the two given possibilities: My view in direct contradiction to Prandtl's legacy was not allowed to be expressed in open scientific discussion. In this case the Prandtl Medal survived but I could not accept to receive it.
The other possibility was that my view in direct contradiction to Prandtl's legacy would have been allowed to be expressed in open scientific discussion. In this case it would have been possible for me to accept the Medal, but further issues of the Prandtl Medal may have become meaningless.
The Organizers chose the first option. The Medal Committee having voted for the second option was apparently run over by the Organizers. But I am still alive and can better express my happy message to the CFD community without the weight of a Prandtl Medal.
Friday July 18:
Dear Professor Johnson,
we already mentioned earlier that a very short award ceremony will take place following the tradition in our associations. This includes a brief introduction of the awardees and a short summary of their major work. Again we would like to point out that it is not possible to enter into a scientific discussion in this ceremony.
However, despite the short notice the organizers found a way for you to express your view in a subsequent CFD session, waived your registration, and include the abstract in the online version of the program. Moreover, your talk will be announced in the ceremony.
We would regret if this arrangement does not meet your expectations and you decide to decline accepting the medal.
Ekkehard Ramm, Pedro Diez, Ferdinando Auricchio, Josef Eberharsteiner- President, Vicepresidents and Secretary of ECCOMAS, Eugenio Oñate, Xavier Oliver, Antonio Huerta - Chairmen of WCCM-ECCM-ECFD 2014
Saturday July 19
Dear Professors and Organizers:
I certainly did not expect to be given the Prandtl Medal, but once being chosen as Medalist I expect a fair and correct reception (including e.g. an invitation to the conference dinner, instead of being asked to invite and pay myself). I thus expect that the following statement of mine (in bold) will be read at the award ceremony, by myself or by the person presenting my person and work:
The famous Danish physicist Niels Bohr said: “How wonderful that we have met with a paradox. Now we have some hope of making progress.”
And yes, to give the Prandtl Medal to me is a paradox, or a contradiction, and as such a starting point for making progress. The contradiction is that my work together with Johan Hoffman has shown that Prandtl’s boundary layer theory, Prandtl’s main contribution as the named Father of Modern Fluid Mechanics, is not in accordance with observations and thus incorrect as scientific theory.
Our evidence consists of computational solutions of the incompressible Navier-Stokes equations as the basic model describing slightly viscous turbulent flow, combined with slip boundary condition as a model of observed small skin friction, which does not generate any no-slip boundary layers, but nevertheless agree with observations of separation, drag and lift for a wide range of problems.
We conclude that separation, drag and lift in slightly viscous flow do not originate from thin no-slip boundary layers, in direct contradiction to Father Prandtl.
Our work breaks the spell of Father Prandtl asking for impossible computational resolution of thin boundary layers beyond the capacity of thinkable computers, and thus opens a wide range of new possibilities for many users of CFD. I will present some of these possibilities in the session Advanced Methods in CFD I following this award ceremony.
I see no rational reason that this statement by me as chosen Medalist cannot be made at the award ceremony. I further expect that a link to the abstract text I have sent will be put up on the conference web page announcing my talk, together with a link to the following related post on my professional blog:
Friday July 18:
Dear Professor Johnson,
we already mentioned earlier that a very short award ceremony will take place following the tradition in our associations. This includes a brief introduction of the awardees and a short summary of their major work. Again we would like to point out that it is not possible to enter into a scientific discussion in this ceremony.
However, despite the short notice the organizers found a way for you to express your view in a subsequent CFD session, waived your registration, and include the abstract in the online version of the program. Moreover, your talk will be announced in the ceremony.
We would regret if this arrangement does not meet your expectations and you decide to decline accepting the medal.
Ekkehard Ramm, Pedro Diez, Ferdinando Auricchio, Josef Eberharsteiner- President, Vicepresidents and Secretary of ECCOMAS, Eugenio Oñate, Xavier Oliver, Antonio Huerta - Chairmen of WCCM-ECCM-ECFD 2014
Saturday July 19
Dear Professors and Organizers:
I certainly did not expect to be given the Prandtl Medal, but once being chosen as Medalist I expect a fair and correct reception (including e.g. an invitation to the conference dinner, instead of being asked to invite and pay myself). I thus expect that the following statement of mine (in bold) will be read at the award ceremony, by myself or by the person presenting my person and work:
The famous Danish physicist Niels Bohr said: “How wonderful that we have met with a paradox. Now we have some hope of making progress.”
And yes, to give the Prandtl Medal to me is a paradox, or a contradiction, and as such a starting point for making progress. The contradiction is that my work together with Johan Hoffman has shown that Prandtl’s boundary layer theory, Prandtl’s main contribution as the named Father of Modern Fluid Mechanics, is not in accordance with observations and thus incorrect as scientific theory.
Our evidence consists of computational solutions of the incompressible Navier-Stokes equations as the basic model describing slightly viscous turbulent flow, combined with slip boundary condition as a model of observed small skin friction, which does not generate any no-slip boundary layers, but nevertheless agree with observations of separation, drag and lift for a wide range of problems.
We conclude that separation, drag and lift in slightly viscous flow do not originate from thin no-slip boundary layers, in direct contradiction to Father Prandtl.
Our work breaks the spell of Father Prandtl asking for impossible computational resolution of thin boundary layers beyond the capacity of thinkable computers, and thus opens a wide range of new possibilities for many users of CFD. I will present some of these possibilities in the session Advanced Methods in CFD I following this award ceremony.
I see no rational reason that this statement by me as chosen Medalist cannot be made at the award ceremony. I further expect that a link to the abstract text I have sent will be put up on the conference web page announcing my talk, together with a link to the following related post on my professional blog:
I further remind you, for the third time, that I want my first name to be presented as Claes and not the double name Claes-Göran, which still occurs on the talk web page.
Looking forward to seeing you tomorrow.
Best regards,
Claes Johnson
Saturday July 19 11.06 PM
Looking forward to seeing you tomorrow.
Best regards,
Claes Johnson
Saturday July 19 11.06 PM
Dear Professor Johnson,
the sole intention of ECCOMAS to select you as the awardee of the 2014 Ludwig Prandtl Medal was to acknowledge your outstanding and sustained contribution in the field of Computational Fluid Dynamics.
Your argument "... that Prandtl has had a devastating negative influence on 20th century fluid mechanics" has nothing to do with this intention. The award ceremony would certainly not be the proper forum for publicly voicing your criticism of Prandtl's boundary layer theory, because it would leave no room for instant counter arguments from the auditorium and, thus, would violate a fundamental principle of a fair scientific dispute.
Therefore, we kindly ask you to withdraw your condition to use the award ceremony for such a criticism. Should you feel unable to do so, we request that you consider not to accept the medal.
If you do not respond to this mail we understand that you will not attend the award ceremony on Monday Morning and that you have decided not accepting the medal.
With best regards,
Ekkehard Ramm, Pedro Diez, Ferdinando Auricchio, Josef Eberharsteiner- President, Vicepresidents and Secretary of ECCOMAS
Eugenio Oñate, Xavier Oliver, Antonio Huerta - Chairmen of WCCM-ECCM-ECFD 2014
Sunday July 21
To ECCOMAS and Organizers of IACM-ECCOMAS Barcelona 2014
After an extended correspondence with representatives of IACM-ECCOMAS, I have come to the conclusion that I cannot accept to receive the Prandtl Medal given to me. The reason is that I have been denied a fair possibility to present my view as the result of my research the last 20 years, that Prandtl's boundary layer theory is not in correspondence with observations and thus incorrect as scientific theory.
My positive message to the CFD community that computational simulation of slightly viscous flow is today possible without resolution of thin no-slip boundary layers, which is in direct contradiction to Prandtl's legacy as the Father of Modern Fluid Mechanics, has not been allowed to be voiced at the conference, except under unreasonable limitation approaching full suppression. This is a tragedy for CFD, ECCOMAS and IACM and I can only hope that reason finally will win.
If there is tomorrow a glimpse of reason, my above motivation for declining the Medal should be read at the award ceremony.
Sincerely,
Claes Johnson
Sunday July 21
To ECCOMAS and Organizers of IACM-ECCOMAS Barcelona 2014
After an extended correspondence with representatives of IACM-ECCOMAS, I have come to the conclusion that I cannot accept to receive the Prandtl Medal given to me. The reason is that I have been denied a fair possibility to present my view as the result of my research the last 20 years, that Prandtl's boundary layer theory is not in correspondence with observations and thus incorrect as scientific theory.
My positive message to the CFD community that computational simulation of slightly viscous flow is today possible without resolution of thin no-slip boundary layers, which is in direct contradiction to Prandtl's legacy as the Father of Modern Fluid Mechanics, has not been allowed to be voiced at the conference, except under unreasonable limitation approaching full suppression. This is a tragedy for CFD, ECCOMAS and IACM and I can only hope that reason finally will win.
If there is tomorrow a glimpse of reason, my above motivation for declining the Medal should be read at the award ceremony.
Sincerely,
Claes Johnson
torsdag 10 juli 2014
Breaking the Spell of Prandtl: From Impossible to Possible CFD
When I accepted to receive the Prandtl Medal I stated as a precondition that my views on Prandtl's legacy as the Father of Modern Fluid Mechanics should be made clear when the award is presented at the opening ceremony and then be combined by an open scientific discussion. I will in the mini-session Advanced Methods in CFD I following the opening ceremony present evidence of the unfortunate dominating influence of Prandtl as the Father of Modern Aerodynamics, which has effectively blocked progress for 100 years, under the title:
- Breaking the Spell of Prandtl: From Impossible to Possible CFD (slides)
with the following abstract:
Our work breaks the spell of Prandtl asking for computational resolution of thin boundary layers which is impossible on any forseeable computer, which has paralyzed CFD since start, by showing that direct computational simulation of turbulent slightly viscous flow is today possible on a supercomputer and tomorrow on a laptop, simply by solving the Navier-Stokes equations with slip boundary conditions using a stabilized finite element method, without any user specified turbulence modeling. This makes CFD of slightly viscous flow possible today for a wide range of users and thus opens many new roads.
As an example of what can be achieved, we have developed a new theory of flight exhibiting the actual fluid mechanics of flying, which has hitherto been hidden. Another is a characterization of slightly viscous incompressible bluff body flow as potential flow modified by 3d rotational slip separation.
More complete presentations are listed under Presentations by CJ on this blog.
To get perspective on the Prandtl Medal (including Medals given to Prandtl), I advise to read and contemplate:
I was surprised of recieving the message that I had been awarded the ECCOMAS 2014 Prandtl Medal, because my work in CFD since 20 years together with Johan Hoffman and his group at KTH gives evidence that Prandtl's main contribution as Father of Modern Fluid Mechanics, his boundary layer theory initiated in his famous 1904 article On Motion of Fluids Flow with Very Little Viscosity claiming that separation, lift and drag in slightly viscous incompressible bluff body flow (Reynolds number larger than $10^6$) all originate from thin no-slip boundary layers, is not in accordance with observations and thus is incorrect as scientific theory (listen to Prandtl expressing his discovery here with perspectives here and here and here, and comment by Euler here).
The evidence consists of computational solutions of the incompressible Navier-Stokes equations with slip boundary condition, which does not generate any no-slip boundary layers and is motivated by the observation that skin friction is small in slightly viscous flow, do agree with observations with the accuracy increasing with increasing Reynolds number. The evidence shows that separation, lift and drag in slightly viscous flow do not originate from no-slip boundary layers.
I have thus been awarded the Prandtl Medal while my main contribution contradicts Father Prandtl himself, a somewhat unusual happening.
As an example of what can be achieved, we have developed a new theory of flight exhibiting the actual fluid mechanics of flying, which has hitherto been hidden. Another is a characterization of slightly viscous incompressible bluff body flow as potential flow modified by 3d rotational slip separation.
More complete presentations are listed under Presentations by CJ on this blog.
To get perspective on the Prandtl Medal (including Medals given to Prandtl), I advise to read and contemplate:
- Making of the Prandtl Myth by John D Anderson
- The Dusk of Fluid Mechanics
- Dr Faustus of Modern Physics
The net result is that I can only accept to receive the Prandtl Medal under the condition that my view that Prandtl was wrong, in several respects, is made clear together with the award.
Here is the statement I have asked to be read by me or the person presenting my work at the award ceremony:
Here is the statement I have asked to be read by me or the person presenting my work at the award ceremony:
The famous Danish physicist Niels Bohr said: “How wonderful that we have met with a paradox. Now we have some hope of making progress.” And yes, to give the Prandtl Medal to me is a paradox, or a contradiction, and as such a starting point for progress.
The contradiction is that my work together with Johan Hoffman has shown that Prandtl’s boundary layer theory, Prandtl’s main contribution as the named Father of Modern Fluid Mechanics, is not in accordance with observations and thus incorrect as scientific theory. Our evidence consists of computational solutions of the incompressible Navier-Stokes equations as the basic model for slightly viscous turbulent flow, combined with slip boundary condition as a model of observed small skin friction, which does not generate any no-slip boundary layers but nevertheless
agree with observation of separation, drag and lift for a wide range of problems.
We conclude that separation, drag and lift in slightly viscous flow do not originate from thin no-slip boundary layers, in direct contradiction to Father Prandtl.
Our work breaks the spell of Prandtl asking for impossible computational resolution of thin boundary layers beyond the capacity of thinkable computers, and thus opens a wide range of new possibilities for many users of CFD. I will present some of these possibilities in the session Advanced Methods in CFD I following this award ceremony.
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