panormus
Guest
se sw fa questo: http://www.youtube.com/watch?feature=player_detailpage&v=eruyiht2x1iof better he will be cautious: you know how?
greetings
greetings
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
Ing Italy
Guest
mmm...so use solidworks to simulate the aerodynamics of an airplane makes me discreetly shiver...I am not an aerospace but cabbage does not seem to me there is nothing physical in that simulation there are not even end vortices!
panormus
Guest
I agree with you. uses solid wind tunnels to have an overall estimate... I thought it was weird. .
However both with catia what kind of reliable estimates can I do in the aeronautical field?
However both with catia what kind of reliable estimates can I do in the aeronautical field?
marcof
Guest
We transcend the obscene quality of the 3d model (starting from the engine, propeller and roof). if the designer of the extra300 sees him causes:smile:mmm...so use solidworks to simulate the aerodynamics of an airplane makes me discreetly shiver...I am not an aerospace but cabbage does not seem to me there is nothing physical in that simulation there are not even end vortices!
It seems to me that the guy "do it yourself" simply "scanned the button" by launching a simulation without even knowing what he was doing. a little game made so much to watch colored figurines. Besides, he says he did it with flowexpress, the simplified module that pulls you behind in the basic version of swx, figurative. . .
Ing Italy
Guest
I know very little catia, reading the site seems to have a close partnership with fluent...it is that catia is the geometric modeler and fluent the solutor.I agree with you. uses solid wind tunnels to have an overall estimate... I thought it was weird. .
However both with catia what kind of reliable estimates can I do in the aeronautical field?
for what I have done I believe that the standard analysis procedure is this: develop a physical sense of the problem that you are analyzing trying to intuit the results/directions characteristic, geometric modeling, you go in design modeler and you clean the geometry (the usual simplifications and cleanings that you always do) with extraction of the fluid volume, in the meshing you go to create the grid calculation of meal (and here you have to reason a nice
I had not used catia as a modeler but I think it is entirely equivalent; to the maximum if catia has inserted some module derived from fluent because they did a collaboration will mean that you will throw everything from the catia module maybe without backing up on the workbench but as I told you I do not know in the specific caia.
However to make simulations with a certain criterion use software dedicated to fluid dynamics because often the modules of the cad are user friendly and, therefore, completely packed... already fluent for a fluid dynamic as well is excessively user friendly, so that usually you go to make real programming.
Bye!
panormus
Guest
but a study like this applies it to the entire aircraft or "problem" in wings, tail planes, melted and then try to intuit its behavior in flight and any parasitic resistances in an approximate way? consider that we speak of aeromodels to reynolds contained, scales between 1/4 and 1/6, with weights in odv of 4-6 kg.
Ing Italy
Guest
depends on what level of analysis you want/you have to get...I am not an aerospace specialized in external aerodynamics of aircraft (I am a mechanic) however:but a study like this applies it to the entire aircraft or "problem" in wings, tail planes, melted and then try to intuit its behavior in flight and any parasitic resistances in an approximate way? consider that we speak of aeromodels to reynolds contained, scales between 1/4 and 1/6, with weights in odv of 4-6 kg.
there are analytical and numerical techniques and I would also say tables that report the characteristics of alar profiles for example naca, one of the techniques that can be used to estimate lifts and dragons is a numrico iterative calculation between motion potential external to the limit layer, obtaining pressure distribution in the potential motion, inserting such distribution in the eqz. of the limit layer, obtaining first estimate dragon, new calculation field of pressure etc.
Why don't you try asking for an opinion in some aerospace forum? they can certainly direct you with more competence, hello! .
Ing Italy
Guest
In my opinion, to do something realistic in this field, it is necessary to be discreetly experienced both of numerical simulation techniques and in particular fluid dynamics (then finite volumes) and of theoretical aerodynamics otherwise it is likely to get so many colored maps, equally colored flow lines but that are not true. . .said this if it is your field try to ask aerospace as recommended above.
panormus
Guest
In principle I follow you, in the sense that I have studied by self-taught the behavior of the alar profiles and its polars, but beyond this I do not go, I am not an aerospace, but I would like to understand more. It is not my intention to go too far into the calculations.. having to deal with aeromodels I can use the personal wind tunnel. . our aeromodellistica track.. to do evidence. :biggrin:
I would simply like to have a more accurate idea in the design phase but without great pretenses.
just to say: ok the surface is well made, aerodynamically can go, I can realize it (in wood or composites).
I ask here because there are very competent people, but I see that work and various commitments often do not allow experts in the field to write me.
Thank you.
I would simply like to have a more accurate idea in the design phase but without great pretenses.
just to say: ok the surface is well made, aerodynamically can go, I can realize it (in wood or composites).
I ask here because there are very competent people, but I see that work and various commitments often do not allow experts in the field to write me.
Thank you.
Ing Italy
Guest
Well if you have wind tunnel is great!if you have the appropriate tools (eg pitot) is fantastic.In principle I follow you, in the sense that I have studied by self-taught the behavior of the alar profiles and its polars, but beyond this I do not go, I am not an aerospace, but I would like to understand more. It is not my intention to go too far into the calculations.. having to deal with aeromodels I can use the personal wind tunnel. . our aeromodellistica track.. to do evidence. :biggrin:
I would simply like to have a more accurate idea in the design phase but without great pretenses.
just to say: ok the surface is well made, aerodynamically can go, I can realize it (in wood or composites).
I ask here because there are very competent people, but I see that work and various commitments often do not allow experts in the field to write me.
Thank you.
if as size you can directly test the aeromodels you are a piece forward because you don't even need to go through the laws of scalation (geometric, kinematics and dynamics) from prototype to model.
I look curious too to see if there are aerodynamics (to which maybe I could ask for some opinion too), hello and good day!
igor azara
Guest
in catia v5 turns a fluent module and anyway I think valid for rapid modeling in prototyping.
for the works of up are used software type ansys for the analysis of mechanical fem surface and fluent (which was acquired by ansys) for the aerodynamic fem
about the analysis of the film, the action of the propeller is completely neglected, which generates important turbulences downstream of the fuselage and the ala-fusoliera connection. This does not remove that in the quick processing of different configurations, one cannot determine the most promising ones to study in detail so:
the aerodynamic domain exported around the aircraft from the catia v5
si mesha( you run the mesh) of the domain or divide the domain into many interconnected elements with aerodynamic properties (depending on the thermal need and others) with software type tgrid or gambit unless the latest versions of ansys-fluent do not have a good integrated meshatore
the boundary conditions for the performance of the differential equations of the aerod system are attributed. speed flow, direction, type, density temperatures etc.
it launches fluent the resolver
the system solves equations in afternoons or days of time depends on how many elements you use.
the results resistors, portance, vortex
However the results have a significant error even up to 20% not for computers as powerful but for formulas that are not exact: they are an acceptable but not perfect model.
you build the model in gallery and measure the aerodynamic characteristics of the model
in fact in ferrari despite the computers, the final configurations are tested in gallery.
for airbus type airlines, parts such as turbofan air vents are further developed in the first flights of prototypes
greetings igor
for the works of up are used software type ansys for the analysis of mechanical fem surface and fluent (which was acquired by ansys) for the aerodynamic fem
about the analysis of the film, the action of the propeller is completely neglected, which generates important turbulences downstream of the fuselage and the ala-fusoliera connection. This does not remove that in the quick processing of different configurations, one cannot determine the most promising ones to study in detail so:
the aerodynamic domain exported around the aircraft from the catia v5
si mesha( you run the mesh) of the domain or divide the domain into many interconnected elements with aerodynamic properties (depending on the thermal need and others) with software type tgrid or gambit unless the latest versions of ansys-fluent do not have a good integrated meshatore
the boundary conditions for the performance of the differential equations of the aerod system are attributed. speed flow, direction, type, density temperatures etc.
it launches fluent the resolver
the system solves equations in afternoons or days of time depends on how many elements you use.
the results resistors, portance, vortex
However the results have a significant error even up to 20% not for computers as powerful but for formulas that are not exact: they are an acceptable but not perfect model.
you build the model in gallery and measure the aerodynamic characteristics of the model
in fact in ferrari despite the computers, the final configurations are tested in gallery.
for airbus type airlines, parts such as turbofan air vents are further developed in the first flights of prototypes
greetings igor
Ing Italy
Guest
Hi.in catia v5... prototypes
greetings igor
How about meshing in ansys-fluent? Does it look like a good tool? .
we say that probably others use it better the wind tunnel (alias red bull)you build the model in gallery and measure the aerodynamic characteristics of the model
in fact in ferrari despite the computers, the final configurations are tested in gallery.
igor azara
Guest
Well now we're red bull. the fluent in 2003 I know for certain that it was used in ferrari because they had consultations with the prof. di ing.aerospaziale di pisa for the back slide. Since then, some stables modeled the entire machine
regarding fem analysis are those that allow to model those strange appendices on the triple alettoni, holes, ducts etc.
the aerodynamics of the cars is different from the aerodynamic bodies (aircrafts) is that of the rough bodies: in the tail are detached of the vortices with a certain periodicity.The fem analysis allow to study the flows to decrease these resistances for e.g.: the duchy van has the lateral edges design of the fanalatura and the variables of the rear edge studied to improve the flows and therefore the resistance and finally the consumption.
regarding fem analysis are those that allow to model those strange appendices on the triple alettoni, holes, ducts etc.
the aerodynamics of the cars is different from the aerodynamic bodies (aircrafts) is that of the rough bodies: in the tail are detached of the vortices with a certain periodicity.The fem analysis allow to study the flows to decrease these resistances for e.g.: the duchy van has the lateral edges design of the fanalatura and the variables of the rear edge studied to improve the flows and therefore the resistance and finally the consumption.