Shape parameter for particles

Post any questions or comments regarding the Desktop PC version of HYSPLIT. This includes the model execution, GUIs, results, or graphics. Be sure to include the operating system you are using (Windows XP, Windows Vista, Windows 7, Windows 8, etc.
Post Reply
arl.noaa
Posts: 33
Joined: November 9th, 2012, 2:49 pm
Registered HYSPLIT User: No

Shape parameter for particles

Post by arl.noaa »

Hi,

I have a question about Hysplit that I haven't been able to answer myself by going through the manual or looking online. In the Concentration / Setup Run / Deposition definition, what are the values for the "Shape" parameter and what do they mean? I notice that Shape is set to 0.0 if the pollutant is a gas and 1.0 if the pollutant is a particle. I didn't know if there were other values or if all particles should be 1.0 and all gasses 0.0.
glenn.rolph
Posts: 362
Joined: November 7th, 2012, 1:39 pm
Registered HYSPLIT User: Yes
Contact:

Re: Shape parameter for particles

Post by glenn.rolph »

See ARL-224 in the documents directory. The shape factor is only applied to particles.

The settling velocity is then adjusted for a slip correction (Cc) for small particles and a dynamic shape factor (α) to account for non-spherical particles. Hence the final settling velocity is

Vs = Vg Cc α-1, (90)

where α can vary between 1.0 to 2.0
Post Reply