Learning Forum

[prashant]

SIMULATION CASE.jpg

[Keyur Kanade]

As ANSYS Staff, we can not download attachments. Please upload images using upload image functionality. n

[prashant]

I am simulating the case mentioned in figure. In this problem liquid nitrogen is coming from a nozzle at an operating pressure of 70 kPa. Actual image during experiment is also attached.nnCan I use surface injection for nozzle as the pressure difference is very less so spray cone formation is negligible? Nozzle geometry is attached for reference.nn

[Amine Ben Hadj Ali]

If there is a cone behavior than better using a solid cone injection so that the streams are dispersed right away. You can still use surface injection but I guess more realistic is a cone liken

[prashant]

I am in full agreement with your advice but I don't have the parameters required for cone injection like cone angle, velocity etc. and cone injection required 3d simulation (I don't know why cone injection is available in axisymmetric model?). So I have chosen surface injection.nI have one more doubt. Since it is written in ansys manual that If you create a surface injection, a particle stream will be released from each facet of the surface. You can use the Bounded and Sample Points options in the Plane Surface panel to create injections from a rectangular grid of particles in 3DnIf I keep all the parameters same (in axisymmetric model) and continue to vary the mesh size of the surface form which particles are getting injected. Then how does ansys satisfy its continuity equation as number of particles getting injected is increasing (with their corresponding diameter) but mass flow rate is fixed.n

[Prashant Srivastava]

why parcel tab in DPM becomes ineffective in cone injection method

My question is
Suppose I am taking solid cone injection with uniform particle diameter of 80 um, now in outer radius tab I entered a value of 100 um and 10 streams are getting introduced at each time step,

It means 10*3.14*(40 um*40 um)  is the area required by the outer radius to accomodate these particles. But fluent accomodes these particles in 100 um outer radius only. Even If I give outer radius as 10 um then also it shows particles in this radius only. How is it possible??

then how fluent shows particle size less than the actual size of droplet in outer radius