Spray angle

[shhe]

I have really misunderstanding to define spray angle for nozzle.How
can I define solid cone and hollow cone angles with 80 degree?

What I have understood for solid angle with 80 degree, I have to
define Lat1 and Lat2 to be 50 and 50 degrees. I do not know if it is
right or not!!!
On the other hand I do not know how can I define it for hollow cone
angle.

[Paul Hart]

This is well described in the Users Manual, page 103.

Your desired nozzle discharge is somewhat unlcear, however I will
assume you want a solid cone of 80 degrees (40 degrees on either side
of nozzle discharge axis). For a solid cone of 80 degrees, Lat1 would
be 0 and Lat2 would be 40. For a hollow cone you need to adjust Lat1
to another angle based on your desired spray pattern. I suggest you
model one nozzle and run several cases, each with different spray
angle so that you can see how it affects the spray pattern.

[shhe]

"For a hollow cone you need to adjust Lat1
to another angle based on your desired spray pattern."

What do you mean by another angle. That is what I need to define
hollow cone spray pattern with discharge angle 80 degree. Now my
problem is how to define lat1 and lat2 for hollow cone.

[drjfloyd]

Using SPRAY_ANGLE, the sprinkler pipe point in the direction of the
south pole. The two angles in SPRAY_ANGLE are measured from the south
pole. If you want a sprinkler with a solid 30 degree cone your inputs
would be 0,15. If you want a 50 degree cone with the inner 20 degrees
hollow your inputs would be 10,25.

[zpe...@gmail.com]

Can you tell me the means of SPRAY_ANGLE(1:2,1)=0,9.25, SPRAY_ANGLE(1:2,2)=0,24 detailedly?Thank you very mucn!



在 2009年8月20日星期四UTC+8下午9时05分15秒，dr_jfloyd写道：

[dr_jfloyd]

Read the current nightly build of the FDS 6 User's Guide (link on the bottom of the fds-smv homepage)

[pei zhu]

&PROP ID='K-11', OFFSET=0.02,
PART_ID='water_drops',OPERATING_PRESSURE=15., FLOW_RATE=1.2,
PARTICLE_VELOCITY=52, PARTICLES_PER_SECOND=50000
,SMOKEVIEW_ID='sprinkler_pendent',SPRAY_ANGLE(1:2,1)=0,9.25,
SPRAY_ANGLE(1:2,2)=0,24/
I did not find in the user guide about the above line ,
and the first spray_angle(1:2,1)=0,9.25 is the longitude ,and the
SPRAY_ANGLE(1:2,2)=0,24 is the latitude, is that right?
but from the smokeview ,I think it is not right?

2013/8/15, dr_jfloyd <drjf...@gmail.com>:

> Read the current nightly build of the FDS 6 User's Guide (link on the bottom
> of the fds-smv homepage)
>

> --
> You received this message because you are subscribed to a topic in the
> Google Groups "FDS and Smokeview Discussions" group.
> To unsubscribe from this topic, visit
> https://groups.google.com/d/topic/fds-smv/13Jz9PiHzz0/unsubscribe.
> To unsubscribe from this group and all its topics, send an email to
> fds-smv+u...@googlegroups.com.
> To post to this group, send email to fds...@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/fds-smv/3f535950-56cc-48fb-a8ef-b8b8c29e5ca3%40googlegroups.com.
> For more options, visit https://groups.google.com/groups/opt_out.
>

[Topi Sikanen]

From the latest FDS_Users guide:

" For exmple, SPRAY\_ANGLE(1,1:2)=0.,60.  and \ct SPRAY\_ANGLE(2,1:2)=0.,30., defines a spray pattern with 60 degree angle in the direction of $x$ axis and a 30 degree angle in the direction of y axis."

So the two refer to the angle in direction of x an y axes (assuming the spray is pointed in negative z direction)

[pei zhu]

thank you very much

2013/8/15, Topi Sikanen <topi.s...@gmail.com>:

> From the latest FDS_Users guide:
>
> " For exmple, SPRAY\_ANGLE(1,1:2)=0.,60. and \ct
> SPRAY\_ANGLE(2,1:2)=0.,30., defines a spray pattern with 60 degree angle in
>
> the direction of $x$ axis and a 30 degree angle in the direction of y
> axis."
>
> So the two refer to the angle in direction of x an y axes (assuming the
> spray is pointed in negative z direction)
>
> On Thursday, August 15, 2013 5:25:50 PM UTC+3, pei zhu wrote:
>>
>> &PROP ID='K-11', OFFSET=0.02,
>> PART_ID='water_drops',OPERATING_PRESSURE=15., FLOW_RATE=1.2,
>> PARTICLE_VELOCITY=52, PARTICLES_PER_SECOND=50000
>> ,SMOKEVIEW_ID='sprinkler_pendent',SPRAY_ANGLE(1:2,1)=0,9.25,
>> SPRAY_ANGLE(1:2,2)=0,24/
>> I did not find in the user guide about the above line ,
>> and the first spray_angle(1:2,1)=0,9.25 is the longitude ,and the
>> SPRAY_ANGLE(1:2,2)=0,24 is the latitude, is that right?
>> but from the smokeview ,I think it is not right?
>>

>> 2013/8/15, dr_jfloyd <drjf...@gmail.com <javascript:>>:

>> > Read the current nightly build of the FDS 6 User's Guide (link on the
>> bottom
>> > of the fds-smv homepage)
>> >
>> > --
>> > You received this message because you are subscribed to a topic in the
>> > Google Groups "FDS and Smokeview Discussions" group.
>> > To unsubscribe from this topic, visit
>> > https://groups.google.com/d/topic/fds-smv/13Jz9PiHzz0/unsubscribe.
>> > To unsubscribe from this group and all its topics, send an email to

>> > fds-smv+u...@googlegroups.com <javascript:>.

>> > To post to this group, send email to

>> > fds...@googlegroups.com<javascript:>.

>>
>> > To view this discussion on the web visit
>> >
>> https://groups.google.com/d/msgid/fds-smv/3f535950-56cc-48fb-a8ef-b8b8c29e5ca3%40googlegroups.com.
>>
>>
>> > For more options, visit https://groups.google.com/groups/opt_out.
>> >
>>
>
> --
> You received this message because you are subscribed to a topic in the
> Google Groups "FDS and Smokeview Discussions" group.
> To unsubscribe from this topic, visit
> https://groups.google.com/d/topic/fds-smv/13Jz9PiHzz0/unsubscribe.
> To unsubscribe from this group and all its topics, send an email to
> fds-smv+u...@googlegroups.com.
> To post to this group, send email to fds...@googlegroups.com.
> To view this discussion on the web visit

> https://groups.google.com/d/msgid/fds-smv/84ec1022-60b5-46e5-aaa2-17c36452aff1%40googlegroups.com.

[pei zhu]

from the Source path: svn/ trunk/ FDS/ trunk/ Validation/ BRE_Spray/
FDS_Input_Files/ BRE_Spray_A_1.fds,the three parameter below,
OPERATING_PRESSURE = 2
K_FACTOR = 0.3889 PARTICLE_VELOCITY = 10
I know thatOPERATING_PRESSURE and K_FACTOR can obtain from the
experiment,but how I can obtain the particle_velocity ,there is a
formula v=c(2△p/ρl)1/2 ,but I can`t obtain the PARTICLE_VELOCITY = 10
? can you give some explanations ?
thank you very much

2013/8/15, pei zhu <zpe...@gmail.com>:

[Marietta_13]

Hi ,

I'm having trouble understanding the definition of the SPRAY_ANGLE in the User Guide. What you've explained above makes sense to me. The user guide states:

SPRAY_ANGLE=30.,80. directs the water droplets to leave the sprinkler through a band between 60 and 10 south latitude, assuming the orientation of the sprinkler is

(0,0,-1), the default.

Should it be that the spray leaves the nozzle through a band between 30° and 80° where measurements of angle are taken from the south latitude?

Thanks in advance

[dr_jfloyd]

SPRAY_ANGLE defines two cones centered on the axis defined by the orientation. The water leaves the sprinkler between the two cones.  the default orientation is -z so the angles are cone angles measured about the z axis.  If you define a North as pointing up and South as pointing down, then 90 south latitude is the south pole.  A cone drawn on the N-S axis that encompasses only the south pole has a cone angle of 0 degrees (the pole is just a point).  A cone drawn on the N-S axis that encompasses 70 south latitude would have a cone angle of 20.