Unstructured grid as a net
- The unstructured grid is a set of net nodes (coordinates) and a set of net links connecting them.
- Flow data is defined on net cells (naming might change). Cells have a (circum-)center (water level point). The entire cell is defined through its contour line (
bounds: NetcellContour_x/y). The contour line contains the coordinates of surrounding net nodes for 2D cells and generated coordinates for 1D channels/manholes/etc.
Examples
- UNSTRUC net file with 2D cells on lon/lat-grid.
- UNSTRUC map file with 2D cells on lon/lat-grid.
- UNSTRUC map file with staggered solution variables (concept)
- UNSTRUC map file with z-layers (concept)
- UNSTRUC map file with sigma coords (concept)
- UNSTRUC map file with subdomains for variable nr of layers (flexible layers, concept)
- Other unstructured models that use netCDF:
UNSTRUC net file with 2D cells on lon/lat-grid.
New version (Mar '10) with additional NetLinkType 0 (closed 2D link/thin dams), and netcell (=NetElem) data + boundary data (intended for use in RGFGRID)
netcdf courantc_net {
dimensions:
nNetNode = 178907 ;
nNetLink = 363286 ;
nNetLinkPts = 2 ;
nBndLink = 14337 ;
nNetElem = 184189 ;
nNetElemMaxNode = 7 ;
variables:
double NetNode_x(nNetNode) ;
NetNode_x:units = "degrees_east" ;
NetNode_x:standard_name = "longitude" ;
NetNode_x:long_name = "netnodal lon-coordinate" ;
double NetNode_y(nNetNode) ;
NetNode_y:units = "degrees_north" ;
NetNode_y:standard_name = "latitude" ;
NetNode_y:long_name = "netnodal lat-coordinate" ;
double NetNode_z(nNetNode) ;
int NetLink(nNetLink, nNetLinkPts) ;
NetLink:standard_name = "netlink" ;
NetLink:long_name = "link between two netnodes" ;
int NetLinkType(nNetLink) ;
NetLinkType:long_name = "type of netlink" ;
NetLinkType:valid_range = 0, 2 ;
NetLinkType:flag_values = 0, 1, 2 ;
NetLinkType:flag_meanings = "closed_link_between_2D_nodes link_between_1D_nodes link_between_2D_nodes" ;
int NetElemNode(nNetElem, nNetElemMaxNode) ;
NetElemNode:long_name = "Mapping from net cell to net nodes." ;
int BndLink(nBndLink) ;
BndLink:long_name = "Netlinks that compose the net boundary." ;
int NetElemLink(nNetElemLink, nNetElemLinkPts) ;
NetElemLink:long_name = "link between two netelems" ;
// global attributes:
:institution = "Deltares" ;
:references = "http://www.deltares.nl" ;
:source = "UNSTRUC v1.0.11.10693:1069, model" ;
:history = "Created on 2010-03-05T09:41:31+0100, UNSTRUC" ;
:Conventions = "CF-1.4:Deltares-0.1" ;
data:
NetNode_x = 10.7736671537707, 10.775, 10.7783013103449, 10.775, 10.775,
10.80625, 10.7839111680939, 10.80625, 10.8375, 10.80625, 10.80625,
// ...
NetLink =
23381, 23382,
32338, 32341,
// ...
NetLinkType = 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 2, 2, 2, 2, 2, 2, 2, 2,
// ...
NetElemNode =
1, 2, 5, _, _, _, _,
1, 5, 4, _, _, _, _,
// ...
BndLink = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,
// ...
UNSTRUC map file with 2D cells on lon/lat-grid.
netcdf test_map {
dimensions:
nNetNode = 178907 ;
nNetLink = 363472 ;
nNetLinkPts = 2 ;
nNetCell = 184324 ;
nNetCellMaxNode = 7 ;
nNetCellContourPts = 99 ;
nNetCellLink = 349141 ;
nNetCellLinkPts = 2 ;
time = UNLIMITED ; // (1 currently)
variables:
double NetNode_x(nNetNode) ;
NetNode_x:units = "degrees_east" ;
NetNode_x:standard_name = "longitude" ;
NetNode_x:long_name = "netnodal lon-coordinate" ;
double NetNode_y(nNetNode) ;
NetNode_y:units = "degrees_north" ;
NetNode_y:standard_name = "latitude" ;
NetNode_y:long_name = "netnodal lat-coordinate" ;
double NetNode_z(nNetNode) ;
int NetLink(nNetLink, nNetLinkPts) ;
NetLink:standard_name = "netlink" ;
NetLink:long_name = "link between two netnodes" ;
int NetLinkType(nNetLink) ;
NetLinkType:standard_name = "netlink_type" ;
NetLinkType:long_name = "type of netlink" ;
NetLinkType:valid_range = 1, 2 ;
NetLinkType:flag_values = 1, 2 ;
NetLinkType:flag_meanings = "link_between_1D_nodes link_between_2D_nodes" ;
double time(time) ;
time:units = "seconds since 2010-01-01 00:00:00" ;
double NetCell_xc(nNetCell) ;
NetCell_xc:units = "degrees_east" ;
NetCell_xc:standard_name = "longitude" ;
NetCell_xc:long_name = "Net cell circumcenter x" ;
NetCell_xc:bounds = "NetCellContour_x" ;
double NetCell_yc(nNetCell) ;
NetCell_yc:units = "degrees_north" ;
NetCell_yc:standard_name = "latitude" ;
NetCell_yc:long_name = "Net cell circumcenter y" ;
NetCell_yc:bounds = "NetCellContour_y" ;
double NetCellContour_x(nNetCell, nNetCellContourPts) ;
NetCellContour_x:units = "degrees_east" ;
NetCellContour_x:standard_name = "longitude" ;
NetCellContour_x:long_name = "List of x-points forming netcell" ;
double NetCellContour_y(nNetCell, nNetCellContourPts) ;
NetCellContour_y:units = "degrees_north" ;
NetCellContour_y:standard_name = "latitude" ;
NetCellContour_y:long_name = "List of y-points forming netcell" ;
int NetCellNode(nNetCell, nNetCellMaxNode) ;
NetCellNode:standard_name = "netcell_node" ;
NetCellNode:long_name = "Mapping from net cell to net nodes (first column is node count, will change)." ;
NetCellNode:netcell_coords = "NetCell_xc NetCell_yc" ;
int NetCellLink(nNetCellLink, nNetCellLinkPts) ;
double s1(time, nNetCell) ;
s1:cell_methods = "area: mean" ;
s1:coordinates = "NetCell_xc Netcell_yc" ;
s1:grid_mapping = "crs" ;
double ucx(time, nNetCell) ;
ucx:cell_methods = "area: point" ;
ucx:coordinates = "NetCell_xc Netcell_yc" ;
ucx:grid_mapping = "crs" ;
double ucy(time, nNetCell) ;
ucy:cell_methods = "area: point" ;
ucy:coordinates = "NetCell_xc Netcell_yc" ;
ucy:grid_mapping = "crs" ;
int crs ;
crs:grid_mapping_name = "latitude_longitude" ;
crs:longitude_of_prime_meridian = 0.f ;
crs:semi_major_axis = 6378137.f ;
crs:inverse_flattening = 298.2572f ;
// global attributes:
:institution = "Deltares" ;
:references = "http://www.deltares.nl" ;
:source = "UNSTRUC v1.0.11.10021:1007, model csmcourant" ;
:history = "Created on 2010-01-06T15:35:40+0100, UNSTRUC" ;
:Conventions = "CF-1.4/Deltares-0.1" ;
data:
NetNode_x = 10.7736671537707, 10.775, 10.7783013103449, 10.775, 10.775,
10.80625, 10.7839111680939, 10.80625, 10.8375, 10.80625, 10.80625,
// ...
NetLink =
80895, 80882,
167568, 167573,
108907, 109422,
// ...
NetLinkType = 1, 1, 1, 1, 1, 1, 1, 1,
// ...
time = 0.0300439515169901 ;
NetCell_xc = 10.7743335768854, 10.7743335913705, 10.7906249344082,
NetCellContour_x =
10.7736671537707, 10.775, 10.775, _, _, _, _, _, // ...
10.775, 10.7783013103449, 10.80625, 10.80625, 10.775, _, _, _, _, _, _, _,
// ...
NetCellNode =
3, 1, 2, 5, _, _, _,
3, 1, 5, 4, _, _, _,
5, 2, 3, 6, 8, 5, _,
// ...
NetCellLink =
1, 2,
1, 3,
// ...
s1 =
4.78405906502741e-001, 5.63697801327623e-001, 2.44636456454523e-001,
7.54911502823542e-001, 2.32821367302938e-001, 1.96039340036838e-001,
5.73297867243609e-001, 2.28008030376163e-001, 3.37509917682617e-001,
// ...
crs = 4326 ;
UNSTRUC map file with staggered solution variables (concept)
TODO: replace normal velocity by u/v at edge?
netcdf test_map {
dimensions:
nNetNode = 706 ;
nNetLink = 1313 ;
nNetLinkPts = 2 ;
nBndLink = 104 ;
nNetElem = 610 ;
nNetElemMaxNode = 7 ;
nFlowElem = 665 ;
nFlowElemMaxNode = 6 ;
nFlowElemContourPts = 99 ;
nNetElemLink1D = 65 ;
nNetElemLink = 1078 ;
nNetElemLinkPts = 2 ;
nFlowLink = 1143 ;
nFlowLinkPts = 2 ;
time = UNLIMITED ; // (1 currently)
variables:
double NetNode_x(nNetNode) ;
NetNode_x:units = "m" ;
NetNode_x:standard_name = "projection_x_coordinate" ;
NetNode_x:long_name = "netnodal x-coordinate" ;
double NetNode_y(nNetNode) ;
NetNode_y:units = "m" ;
NetNode_y:standard_name = "projection_y_coordinate" ;
NetNode_y:long_name = "netnodal y-coordinate" ;
double NetNode_z(nNetNode) ;
int NetLink(nNetLink, nNetLinkPts) ;
NetLink:standard_name = "netlink" ;
NetLink:long_name = "link between two netnodes" ;
int NetLinkType(nNetLink) ;
NetLinkType:long_name = "type of netlink" ;
NetLinkType:valid_range = 0, 2 ;
NetLinkType:flag_values = 0, 1, 2 ;
NetLinkType:flag_meanings = "closed_link_between_2D_nodes link_between_1D_nodes link_between_2D_nodes" ;
int NetElemNode(nNetElem, nNetElemMaxNode) ;
NetElemNode:long_name = "Mapping from net cell to net nodes." ;
int BndLink(nBndLink) ;
BndLink:long_name = "Netlinks that compose the net boundary." ;
double time(time) ;
time:units = "seconds since 1992-08-31 00:00:00" ;
double FlowElem_xcc(nFlowElem) ;
FlowElem_xcc:units = "m" ;
FlowElem_xcc:standard_name = "projection_x_coordinate" ;
FlowElem_xcc:long_name = "Flow element circumcenter x" ;
FlowElem_xcc:bounds = "FlowElemContour_x" ;
double FlowElem_ycc(nFlowElem) ;
FlowElem_ycc:units = "m" ;
FlowElem_ycc:standard_name = "projection_y_coordinate" ;
FlowElem_ycc:long_name = "Flow element circumcenter y" ;
FlowElem_ycc:bounds = "FlowElemContour_y" ;
double FlowElemContour_x(nFlowElem, nFlowElemContourPts) ;
FlowElemContour_x:units = "m" ;
FlowElemContour_x:standard_name = "projection_x_coordinate" ;
FlowElemContour_x:long_name = "List of x-points forming flow element" ;
double FlowElemContour_y(nFlowElem, nFlowElemContourPts) ;
FlowElemContour_y:units = "m" ;
FlowElemContour_y:standard_name = "projection_y_coordinate" ;
FlowElemContour_y:long_name = "List of y-points forming flow element" ;
int FlowLink(nFlowLink, nFlowLinkPts) ;
FlowLink:long_name = "link/interface between two flow elements" ;
int FlowLinkType(nFlowLink) ;
FlowLinkType:long_name = "type of flowlink" ;
FlowLinkType:valid_range = 1, 2 ;
FlowLinkType:flag_values = 1, 2 ;
FlowLinkType:flag_meanings = "link_between_1D_flow_elements link_between_2D_flow_elements" ;
double FlowLink_xu(nFlowLink) ;
FlowLink_xu:long_name = "Center coordinate of net link (velocity point)." ;
FlowLink_xu:units = "m" ;
FlowLink_xu:standard_name = "projection_x_coordinate" ;
double FlowLink_yu(nFlowLink) ;
FlowLink_yu:long_name = "Center coordinate of net link (velocity point)." ;
FlowLink_yu:units = "m" ;
FlowLink_yu:standard_name = "projection_y_coordinate" ;
double s1(time, nFlowElem) ;
s1:coordinates = "FlowElem_xcc FlowElem_ycc" ;
double ucx(time, nFlowElem) ;
ucx:coordinates = "FlowElem_xcc FlowElem_ycc" ;
double ucy(time, nFlowElem) ;
ucy:coordinates = "FlowElem_xcc FlowElem_ycc" ;
double unorm(time, nFlowLink) ;
unorm:standard_name = "normal_velocity" ;
unorm:units = "m s-1" ;
unorm:interfaces = "FlowLink" ;
unorm:coordinates = "FlowLink_xu FlowLink_yu" ;
// global attributes:
:institution = "Deltares" ;
:references = "http://www.deltares.nl" ;
:source = "UNSTRUC v1.0.11.10693:1069, model" ;
:history = "Created on 2010-03-08T13:23:31+0100, UNSTRUC" ;
:Conventions = "CF-1.4:Deltares-0.1" ;
data:
NetNode_x = 1078.99694824, 1068.75195312, 1110.4510498, 1123.6159668,
1032.6619873, 1023.13500977, 984.9420166, 974.37200928, 936.1550293,
922.88897705, 886.71002197, 868.85601807, 837.2210083, 812.21697998,
// ...
time = 10.7142857142857 ;
FlowElem_xcc = 1800.29010953126, 1827.13454757167, 1892.73565627098,
// ...
FlowElemContour_x =
1799.14001465, 1843.04504395, 1796.97290039, 1758.60998535, _, _, _, _, _,
_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _,
_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _,
_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _,
_, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _, _,
// ...
FlowLink =
1, 2,
2, 9,
UNSTRUC map file with z-layers (concept)
netcdf test_map {
dimensions:
nNetNode = 706 ;
nNetLink = 1313 ;
nNetLinkPts = 2 ;
nFlowElem = 665 ;
nFlowElemMaxNode = 6 ;
nFlowElemContourPts = 99 ;
nFlowLink = 1143 ;
nFlowLinkPts = 2 ;
nLayer = 5;
time = UNLIMITED ; // (1 currently)
variables:
double NetNode_x(nNetNode) ;
NetNode_x:units = "m" ;
NetNode_x:standard_name = "projection_x_coordinate" ;
NetNode_x:long_name = "netnodal x-coordinate" ;
double NetNode_y(nNetNode) ;
NetNode_y:units = "m" ;
NetNode_y:standard_name = "projection_y_coordinate" ;
NetNode_y:long_name = "netnodal y-coordinate" ;
double NetNode_z(nNetNode) ;
int NetLink(nNetLink, nNetLinkPts) ;
NetLink:standard_name = "netlink" ;
NetLink:long_name = "link between two netnodes" ;
int NetLinkType(nNetLink) ;
NetLinkType:long_name = "type of netlink" ;
NetLinkType:valid_range = 0, 2 ;
NetLinkType:flag_values = 0, 1, 2 ;
NetLinkType:flag_meanings = "closed_link_between_2D_nodes link_between_1D_nodes link_between_2D_nodes" ;
double time(time) ;
time:units = "seconds since 1992-08-31 00:00:00" ;
double FlowElem_xcc(nFlowElem) ;
FlowElem_xcc:units = "m" ;
FlowElem_xcc:standard_name = "projection_x_coordinate" ;
FlowElem_xcc:long_name = "Flow element circumcenter x" ;
FlowElem_xcc:bounds = "FlowElemContour_x" ;
double FlowElem_ycc(nFlowElem) ;
FlowElem_ycc:units = "m" ;
FlowElem_ycc:standard_name = "projection_y_coordinate" ;
FlowElem_ycc:long_name = "Flow element circumcenter y" ;
FlowElem_ycc:bounds = "FlowElemContour_y" ;
double FlowElemContour_x(nFlowElem, nFlowElemContourPts) ;
FlowElemContour_x:units = "m" ;
FlowElemContour_x:standard_name = "projection_x_coordinate" ;
FlowElemContour_x:long_name = "List of x-points forming flow element" ;
double FlowElemContour_y(nFlowElem, nFlowElemContourPts) ;
FlowElemContour_y:units = "m" ;
FlowElemContour_y:standard_name = "projection_y_coordinate" ;
FlowElemContour_y:long_name = "List of y-points forming flow element" ;
int FlowLink(nFlowLink, nFlowLinkPts) ;
FlowLink:long_name = "link/interface between two flow elements" ;
int FlowLinkType(nFlowLink) ;
FlowLinkType:long_name = "type of flowlink" ;
FlowLinkType:valid_range = 1, 2 ;
FlowLinkType:flag_values = 1, 2 ;
FlowLinkType:flag_meanings = "link_between_1D_flow_elements link_between_2D_flow_elements" ;
double FlowLink_xu(nFlowLink) ;
FlowLink_xu:long_name = "Center coordinate of net link (velocity point)." ;
FlowLink_xu:units = "m" ;
FlowLink_xu:standard_name = "projection_x_coordinate" ;
double FlowLink_yu(nFlowLink) ;
FlowLink_yu:long_name = "Center coordinate of net link (velocity point)." ;
FlowLink_yu:units = "m" ;
FlowLink_yu:standard_name = "projection_y_coordinate" ;
double FlowElem_zc(nFlowElem, nLayer) ;
FlowElem_zc:long_name = "Vertical coordinates of layers underlying each FlowElement." ;
FlowElem_zcc:units = "m" ;
FlowElem_zc:layer_type = "z" ; // see other example for sigma
FlowElem_zc:standard_name = "???" ;
double FlowElem_bl(nFlowElem) ;
FlowElem_bl:units = "m" ;
FlowElem_bl:long_name = "bottom level" ;
FlowElem_bl:standard_name = "sea_floor_depth" ; // wrt geoid, maar doen wij dat wel zo?
double s1(time, nFlowElem) ;
s1:coordinates = "FlowElem_xcc FlowElem_ycc" ;
double ucx(time, nFlowElem, nLayer) ;
ucx:coordinates = "FlowElem_xcc FlowElem_ycc" ;
double ucy(time, nFlowElem, nLayer) ;
ucy:coordinates = "FlowElem_xcc FlowElem_ycc FlowElem_zcc" ; // AvD: Mogen de z-coordinaten hier ook nog bij? (nFlowElem mapt naar x+y, nLayer naar z)
UNSTRUC map file with sigma coords (concept)
netcdf test_map {
dimensions:
nNetNode = 706 ;
nNetLink = 1313 ;
nNetLinkPts = 2 ;
nFlowElem = 665 ;
nFlowElemMaxNode = 6 ;
nFlowElemContourPts = 99 ;
nFlowLink = 1143 ;
nFlowLinkPts = 2 ;
nLayer = 5;
time = UNLIMITED ; // (1 currently)
variables:
double FlowElem_bl(nFlowElem) ;
FlowElem_bl:units = "m" ;
FlowElem_bl:long_name = "bottom level" ;
FlowElem_bl:standard_name = "sea_floor_depth" ; // wrt geoid, maar doen wij dat wel zo?
double FlowElem_zc(nFlowElem, nLayer) ;
FlowElem_zc:long_name = "Vertical coordinates of layers underlying each FlowElement." ;
FlowElem_zc:units = "" ;
FlowElem_zc:standard_name = "ocean_sigma_coordinate" ;
FlowElem_zc:formula_terms = "sigma: FlowElem_zc eta: s1 depth: FlowElem_bl" ; // mooie oplossing: bottomlevel (en sigma/zc) mag tijdsonafhankelijk zijn
double s1(time, nFlowElem) ;
s1:coordinates = "FlowElem_xcc FlowElem_ycc" ;
double ucx(time, nFlowElem, nLayer) ;
ucx:coordinates = "FlowElem_xcc FlowElem_ycc" ;
// ...
UNSTRUC map file with subdomains for variable nr of layers (flexible layers, concept)
netcdf test_map {
dimensions:
nNetNode1 = 106 ;
nNetLink1 = 313 ;
nNetLinkPts1 = 2 ;
nFlowElem1 = 165 ;
nFlowElemMaxNode1 = 6 ;
nFlowElemContourPts1 = 99 ;
nFlowLink1 = 343 ;
nFlowLinkPts1 = 2 ;
nLayer1 = 5;
nNetNode2 = 486 ;
nNetLink2 = 673 ;
nNetLinkPts2 = 2 ;
nFlowElem2 = 578 ;
nFlowElemMaxNode2 = 6 ;
nFlowElemContourPts2 = 99 ;
nFlowLink2 = 840 ;
nFlowLinkPts2 = 2 ;
nLayer2 = 10 ;
// ... idem for 3 and 4
nSubdomain = 4 ;
nSubdomainLink = 3 ; // for example: 4 subdoms in one row
nSubdomainLinkPts = 2 ;
time = UNLIMITED ; // (1 currently)
variables:
double NetNode_x_1(nNetNode1) ;
NetNode_x_1:units = "m" ;
NetNode_x_1:standard_name = "projection_x_coordinate" ;
NetNode_x_1:long_name = "netnodal x-coordinate" ;
// ...
double NetNode_x_2(nNetNode1) ;
NetNode_x_2:units = "m" ;
NetNode_x_2:standard_name = "projection_x_coordinate" ;
NetNode_x_2:long_name = "netnodal x-coordinate" ;
double s1_1(time, nFlowElem_1) ;
s1_1:coordinates = "FlowElem_xcc_1 FlowElem_ycc_1" ;
double s1_2(time, nFlowElem_2) ;
s1_2:coordinates = "FlowElem_xcc_2 FlowElem_ycc_2" ;
// ...
integer SubdomainLink (nSubdomainLink, nSubdomainLinkPts) ;
SubdomainLink:long_name = "Meta link between subdomain numbers."
// .. randlinks tussen subdomains kunnen nuttig zijn, maar zijn ws niet nodig voor visualisatie?
integer Subdomain ;
Subdomain:interfaces = "SubdomainLink"
data:
SubdomainLink =
1, 2,
2, 3,
3, 4 ;
Subdomain = 4; // weinig bijzonders.
