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start:hype_model_description:hype_routing [2018/08/10 15:50]
cpers [Simple outlet lake or dam (olake)]
start:hype_model_description:hype_routing [2018/10/18 16:27] (current)
cpers [Initalisation of lake volume]
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-The HYPE model can contain two types of rivers, local stream and main river, and two types of lakes, local lakes and outlet lakes (Figure 1). Local and main rivers are present in all subbasins and the length of each is calculated as the square root of the subbasin area. For main rivers, the length of the watercourse in each subbasin ​can be given as input (>0). The river can be a SLC class and is then given an area, but rivers can also be one-dimensional (i.e. no part of subbasin area are occupied by the river and no precipitation added to the river). All local runoff is entering the local river. If there are upstream subbasins ​the flow is added to the local runoff and two both flow through ​the main river. Outlet lakes (olake) receive all upstream and local waters. Local lakes (ilake) receive a portion of the local runoff.+The HYPE model can contain two types of rivers, local stream and main river, and two types of lakes, local lakes and outlet lakes (Figure 1). Local and main rivers are present in all subbasins and the length of each is calculated as the square root of the subbasin area. The length of the watercourses ​can be given as input. The river can be a SLC class and is then given an area, but rivers can also be one-dimensional (i.e. no fraction ​of the subbasin area are occupied by the river and no precipitation added to the river). All local runoff is entering the local river. Local lakes (ilake) receive a portion of the local runoff. The flow leaving the local river (including flow from local lake) goes to the main river of the same subbasin. If there are upstream subbasins ​their flow is added to the local flow when both flows flow into the main river. Outlet lakes (olake) receive ​the outflow from the main river, i.e. all upstream and local flows.
  
 |{{:​start:​hype_model_description:​lakeriveroverview.png?​400|}}| |{{:​start:​hype_model_description:​lakeriveroverview.png?​400|}}|
 |Figure 1: Schematic representation of streams and lakes i HYPE, and the link between them.| |Figure 1: Schematic representation of streams and lakes i HYPE, and the link between them.|
  
-The two lake types are separate classes. ​Which land use and soil type that are coupled to each lake type are listed ​in GeoClass.txt. Precipitation,​ atmospheric deposition and evaporation of rivers and lakes are calculated first, while river flow and inflow, transformation processes and the outflow of the lakes is calculated thereafter. Lakes and rivers are calculated in the model’s routing part after all classes are calculated for the subbasin. ​+The two lake types are separate classes. ​The lake classes have characteristics such as land use and soil type, which are defined together with the other classes'​ characteristics (in GeoClass.txt). Precipitation,​ atmospheric deposition and evaporation of rivers and lakes are calculated first, while river flow and inflow, transformation processes and the outflow of the lakes is calculated thereafter. Lakes and rivers are calculated in the model’s routing part after all classes are calculated for the subbasin. ​
  
 An outlet lake can be part of a larger lake. It is then called a lake basin. Lake basins are olakes in nearby subbasins. Outlet lakes that are not lake basins are referred to below as simple outlet lakes. ​ An outlet lake can be part of a larger lake. It is then called a lake basin. Lake basins are olakes in nearby subbasins. Outlet lakes that are not lake basins are referred to below as simple outlet lakes. ​
  
-A simple outlet lake has a threshold. The outflow ends if the water level drops below the threshold. Lake mean depth below the threshold is specified in GeoData.txt or LakeData.txt as lake_depth in meters. Lake depth can also be set by parameters, i.e general parameter //gldepo// or olake region parameter //​olldepth//​. The threshold is also the the water level of the lake at the start of a simulation. The current water level is denoted as //wlm// in Fig. 2. For printing, the outlet lake water level (output variable //wcom//) is calculated in meters and you can set a reference level (//w0ref//) in LakeData.txt to get the same height system as any observations of the lake's water level. The lake’s //w0ref// is added to the water level above the threshold. It is possible to adjust the output //wcom// for the actual amplitude of the regulation volume (//wamp//), this may be useful because ​the lake is assumed to have vertical sides in the calculations.+A simple outlet lake has a threshold. The outflow ends if the water level drops below the threshold. Lake mean depth below the threshold is specified in GeoData.txt or LakeData.txt as //lake_depth// in meters. Lake depth can also be set by parameters, i.e general parameter //gldepo// or olake region parameter //​olldepth//​. The threshold is also the the water level of the lake at the start of a simulation. The current water level is denoted as //wlm// in Fig. 2. For printing, the outlet lake water level (output variable //wcom//) is calculated in meters and you can set a reference level (//w0ref//) in LakeData.txt to get the same height system as any observations of the lake's water level. The lake’s //w0ref// is added to the water level above the threshold. HYPE assumes the lake has vertical sides in the calculations,​ thus the observed variation may be larger than the simulated variation. It is therefore ​possible to adjust the output //wcom// for the actual amplitude of the regulation volume (//wamp//). This will make the simulated and recorded water stage comparable below the threshold for a regulated ​lake. 
  
 |{{:​start:​hype_model_description:​outletlakewithvariables2.png?​400|}}| |{{:​start:​hype_model_description:​outletlakewithvariables2.png?​400|}}|
 |Figure 2: An outlet lake with some variables.| |Figure 2: An outlet lake with some variables.|
  
-A local lake also has a threshold depth that is used as start value. The depth is given by general parameter gldepi and is then the same for all the local lakes, or by ilake region parameter illdepth. It is measured in meters. A percentage of flow from the local stream flows into the local lake. The rest of the local flow runs directly to main river watercourse. ​+A local lake also has a threshold depth that is used as start value. The depth is given by general parameter ​//gldepi// and is then the same for all the local lakes, or by ilake region parameter ​//illdepth//. It is measured in meters. A percentage of flow from the local stream flows into the local lake. The rest of the local flow runs directly to main river watercourse. ​
  
 Using parameters, you can divide the lake into two parts, one with faster flows (FLP) and one with slower flows (SLP) (Figure 3). This function is used for the simulation of nutrients to simulate stratification,​ strangulation or other phenomena that may limit the mixing of a lake. With this feature, the flows through the lake follow the schedule below. The split is determined by the parameter //​deeplake//,​ which is the fraction of the lake's initial volume SLP, the remaining (varying) volume in the lake is the FLP. The parameter //​fastlake//​ determines where the outflow will be coming from. Default is that outflow is taken from the slow lake part. Increasing //​fastlake//​ will let the FLP contribute to outflow. //​Fastlake//​ equal to one gives the maximum contribution of FLP, and the outflow will be taken proportionally from the two lake parts according to their volume. Using parameters, you can divide the lake into two parts, one with faster flows (FLP) and one with slower flows (SLP) (Figure 3). This function is used for the simulation of nutrients to simulate stratification,​ strangulation or other phenomena that may limit the mixing of a lake. With this feature, the flows through the lake follow the schedule below. The split is determined by the parameter //​deeplake//,​ which is the fraction of the lake's initial volume SLP, the remaining (varying) volume in the lake is the FLP. The parameter //​fastlake//​ determines where the outflow will be coming from. Default is that outflow is taken from the slow lake part. Increasing //​fastlake//​ will let the FLP contribute to outflow. //​Fastlake//​ equal to one gives the maximum contribution of FLP, and the outflow will be taken proportionally from the two lake parts according to their volume.
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 +==== Links to file reference ====
 +
 +^Parameter/​Data ^File ^
 +|//rivlen, loc_rivlen, slc_nn//​|[[start:​hype_file_reference:​geodata.txt|GeoData.txt]]|
 +|special class code 1,2,11 and 12|[[start:​hype_file_reference:​geoclass.txt|GeoClass.txt]]|
 +|//​lake_depth//​|[[start:​hype_file_reference:​geodata.txt|GeoData.txt]] or [[start:​hype_file_reference:​lakedata.txt|LakeData.txt]] or [[start:​hype_file_reference:​damdata.txt|DamData.txt]]|
 +|//gldepo, olldepth, gldepi, illdepth//​|[[start:​hype_file_reference:​par.txt|par.txt]]|
 +|//w0ref, wamp//​|[[start:​hype_file_reference:​lakedata.txt|LakeData.txt]] or [[start:​hype_file_reference:​damdata.txt|DamData.txt]]|
 +|//​deeplake,​ fastlake//​|[[start:​hype_file_reference:​par.txt|par.txt]]|
 ==== Links to relevant modules in the code ==== ==== Links to relevant modules in the code ====
  
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 === Precipitation === === Precipitation ===
  
-Daily precipitation is added to the river if it has an area and a new concentration is calculated. Precipitation is divided between river water in damping box and queue according to the respective volumes.+Daily precipitation is added to the river if it has an area (is a class) ​and a new concentration is calculated. Precipitation is divided between river water in damping box and queue according to the respective volumes.
  
 === Evaporation === === Evaporation ===
  
-If the river has an area (is a class), it evaporates and a new concentration is calculated. Normally the river area is constant over time, but with parameters ​can a reduction of riverarea be simulated for low volume/​flow. The reduced river area is also used for heat exchange calculations.+If the river has an area (is a class), it evaporates and a new concentration is calculated. Normally the river area is constant over time, but with parameters a reduction of riverarea ​can be simulated for low volume/​flow. The reduced river area is also used for heat exchange calculations.
  
 <m> frac_area = delim{lbrace}{ ​ <m> frac_area = delim{lbrace}{ ​
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     }}{} </m>     }}{} </m>
        
-The parameters //fraxe// and //fraxm// are general, and //fraxe// is (minimum) mean river depth (m) where fractional river area = 1 and //fraxm// is mean river depth (m) where the slope of the fractional river area has its maximum (must be in the range between 0 and //fraxe//).+The parameters //fraxe// and //fraxm// are general, and //fraxe// is (minimum) mean river depth (m) where fractional river area = 1 and //fraxm// is mean river depth (m) where the slope of the fractional river area has its maximum (must be in the range between 0 and //fraxe//). //x// is the current mean river depth (based on full area extention).
  
 === Pure delay === === Pure delay ===
  
-The delay in the watercourse (//​transtime//​) in days is determined by the length of the watercourse (//​rivlen//​) and the water’s maximum velocity (//​rivvel//​). The maximum velocity is a general parameter with unit //m/s//. The delay in the local river is dependent on subbasin ​size, as stream length calculated from its area. The delay is a pure translation. The delay is divided into whole days (//ttday//) and parts of the day (//​ttpart//​).+The delay in the watercourse (//​transtime//​) in days is determined by the length of the watercourse (//​rivlen//​) and the water’s maximum velocity (//​rivvel//​). The maximum velocity is a general parameter with unit //m/s//. The delay in the river is dependent on subbasin ​land area if the default river length is used. The delay is a pure translation. The delay is divided into whole days (//ttday//) and parts of the day (//​ttpart//​).
  
 <m> transtime = rivlen/​{rivvel*8.64*10^4} </m> <m> transtime = rivlen/​{rivvel*8.64*10^4} </m>
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 <m> ttpart = transtime - REAL(ttday) </m> <m> ttpart = transtime - REAL(ttday) </m>
  
-The inflow of the river is stored in two arrays (//riverq// and //riverc//) until it is time for it to drain out. The outflow is weighted by using the parts of the day that are during the time step.+The inflow of the river is stored in two arrays (//riverq// and //riverc//) until it is time for it to flow out of the river stretch. The outflow is weighted by using the parts of the time step (//​ttpart//​) ​that are to flow out during the time step.
  
   transq = (1-ttpart)*riverq(ttday) + ttpart*riverq(ttday+1)   transq = (1-ttpart)*riverq(ttday) + ttpart*riverq(ttday+1)
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   ENDIF   ENDIF
  
-After the calculation of outflow the values in the arrays are shifted forward one day+After the calculation of outflow the values in the arrays are shifted forward one time step
  
 === Delay and attenuation === === Delay and attenuation ===
  
-If the delay in the watercourse also includes a damping of the peaks then part of the delay is considered as translation,​ while some of the delay lies in damping. The translation is calculated first and then the flow goes through a linear box that creates ​damping. The parameter damp indicates how much of the delay that will occur in the attenuation box, and translation time is reduced accordingly. Otherwise the translation is calculated in the same manner as above.+If the delay in the watercourse also includes a damping of the peaks then only part of the delay is considered as translation,​ while the rest of the delay lies in damping. The translation is calculated first and then the flow goes through a linear box that creates ​attenuation. The parameter damp indicates how much of the delay that will occur in the attenuation box (or damping box), and translation time is reduced accordingly. Otherwise the translation is calculated in the same manner as above.
  
-<m> totaltime=rivlen/​{rivvel~8.64~10^4} </m>+<m> totaltime=rivlen/​{rivvel*8.64~10^4} </m>
  
 <m> transtime=(1-damp)*totaltime </m> <m> transtime=(1-damp)*totaltime </m>
  
-The result from the translation (//transq// and //​transc//​) ​goes into the damping box. Translation flow is added to the suppression ​box, which is assumed to be completely mixed. The delay time in the attenuation ​box (//kt//) is translated ​to a corresponding recession coefficient (//​riverrc//​). The recession coefficient used to calculate the outflow from the box (//dampq//) is a function of volume in the box (//​riverbox//​).+The result from the translation ​of water (//transq// and //​transc//​) ​flows into the attenuation ​box, which is assumed to be completely mixed. The delay time in the box (//kt//) is recalculated ​to a corresponding recession coefficient (//​riverrc//​). The recession coefficient ​(//​riverrc//​) ​used to calculate the outflow from the box (//dampq//) is a function of volume in the box (//​riverbox//​).
  
 <m> kt = damp * totaltime </m> <m> kt = damp * totaltime </m>
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 ==== Local river ==== ==== Local river ====
  
-The local river has a length equal to the square root of the subbasin area. Subbasin runoff ​forms the inflow to the local river. The flow in the local river is delayed and attenuated as described above. Of the resulting flow from the stream a constant percentage goes to the local lake, and the rest directly to the main river. ​+The local river has a length equal to the square root of the subbasin area, if not specified as inputRunoff from the land area of the subbasin ​forms the inflow to the local river. The flow in the local river is delayed and attenuated as described above. Of the resulting flow from the stream a constant percentage goes to the local lake (//​icatch//​), and the rest directly to the main river. ​
  
 ==== Main river ==== ==== Main river ====
  
-A main river is present in all subbasins. The length is equal to the square root of the subbasin area, if it is not specified ​in GeoData.txt. In areas without incoming water from upstream there is still a main river, but it receives only local river flow after the local lake. In subbasins with upstream incoming water, the flow to the main river will be the sum of outflow from the local lake, the proportion of flow in the local river not flowing into the local lake and the water from upstream.+A main river is present in all subbasins. The length is equal to the square root of the subbasin area, if it is not specified ​as input. In areas without incoming water from upstream there is still a main river, but it receives only local river flow after the local lake. In subbasins with upstream incoming water, the flow to the main river will be the sum of outflow from the local lake, the proportion of flow in the local river not flowing into the local lake and the water from upstream.
  
 The return flow from an aquifer is added to the inflow of the main river. The return flow from an aquifer is added to the inflow of the main river.
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 === Inflow from upstream subbasins === === Inflow from upstream subbasins ===
  
-In GeoData.txt ​it is given to which subbasin(s) the (main) ​outflow from each subbasin flows. The upstream flow enters the main river of the downstream subbasin. Inflow into the main river of a subbasin is calculated by adding outflows from upstream areas. Concentrations are flow-weighted by their relative share. ​+In input files it is given to which subbasin(s) the outflow from each subbasin flows. The upstream flow enters the main river of the downstream subbasin. Inflow into the main river of a subbasin is calculated by adding outflows from upstream areas. Concentrations are flow-weighted by their relative share. ​ 
 + 
 + 
 +==== Links to file reference ==== 
 + 
 +^Section ^Symbol ^Parameter/​Data ^File ^ 
 +|Common rivers processes|//​rivlen//​|//​rivlen,​ loc_rivlen//​|[[start:​hype_file_reference:​geodata.txt|GeoData.txt]]| 
 +|:::​|//​fraxe,​ fraxm, rivvel, damp//​|//​fraxe,​ fraxm, rivvel, damp//​|[[start:​hype_file_reference:​par.txt|par.txt]]| 
 +|:::​|//​dead//​|//​deadm,​ deadl//​|:::​| 
 +|Local river| |//​icatch//​|[[start:​hype_file_reference:​geodata.txt|GeoData.txt]]| 
 +|:::| |//gicatch, illicatch//​|[[start:​hype_file_reference:​par.txt|par.txt]]| 
 +|Main river| |//​maindown//​|[[start:​hype_file_reference:​geodata.txt|GeoData.txt]]| 
 +|:::| |//​branchid//​|[[start:​hype_file_reference:​branchdata.txt|BranchData.txt]]|
  
 ==== Links to relevant modules in the code ==== ==== Links to relevant modules in the code ====
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 The local lake has an initial volume which is determined by its area and threshold depth. The lake depth is determined by model parameters (//gldepi// or //​illdepth//​)). ​ The local lake has an initial volume which is determined by its area and threshold depth. The lake depth is determined by model parameters (//gldepi// or //​illdepth//​)). ​
  
-The inflow to the lake is a percentage of the flow in the local stream. The percentage is determined by the percentage of the subbasin area that drain to the lake. This percentage can be given as a fraction in GeoData.txt (//​icatch//​) for each subbasin with an internal lake, or be given by a regional parameter //​ilicatch//,​ or be given by a general parameter //​gicatch//​. If not set at all the default value is 1, i.e. the local river runs through the loacal ​lake. The flow from the local river is added to the lake. The lake water is assumed completely mixed if //deeplake = 0//. +The inflow to the lake is a percentage of the flow in the local stream. The percentage is determined by the percentage of the subbasin area that drain to the lake. This percentage can be given as a fraction in GeoData.txt (//​icatch//​) for each subbasin with an internal lake, or be given by a regional parameter //​ilicatch//,​ or be given by a general parameter //​gicatch//​. If not set at all the default value is 1, i.e. the local river runs through the local lake. The flow from the local river is added to the lake. The lake water is assumed completely mixed if //deeplake = 0//. 
  
 Water outflow is calculated with the universal rating curve using general or region specific model parameters. Water outflow is calculated with the universal rating curve using general or region specific model parameters.
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 Input variables //rate, exp, qprod, regvol, w0, qamp// and //qpha// can be found in LakeData.txt. The variable //wmin// is calculated by the program from //regvol// and lake area: Input variables //rate, exp, qprod, regvol, w0, qamp// and //qpha// can be found in LakeData.txt. The variable //wmin// is calculated by the program from //regvol// and lake area:
  
-<​m> ​ wmin = w0 – regvol * 1000000 / area </m>+<​m> ​ wmin = w0 regvol * 1000000 / area </m>
  
 Production flow can have two different values during the year, which depends on the day of the year. This is determined by the input variables //qprod1, qprod2, datum1// and //datum2//. Regulation period 1 between //datum1// and //datum2// has production flow //qprod1//, while the rest of the year has production flow //qprod2//. Not setting the dates gives the same production flow the whole year (//​qprod1//​). Production flow can alternatively be made to vary sinusoidal over the years, with a peak in December, when power output is normally high, and a minimum in June. This is done with the input variable //qamp//. If you want a different seasonal variation set //qpha// (default = 102). Production flow can have two different values during the year, which depends on the day of the year. This is determined by the input variables //qprod1, qprod2, datum1// and //datum2//. Regulation period 1 between //datum1// and //datum2// has production flow //qprod1//, while the rest of the year has production flow //qprod2//. Not setting the dates gives the same production flow the whole year (//​qprod1//​). Production flow can alternatively be made to vary sinusoidal over the years, with a peak in December, when power output is normally high, and a minimum in June. This is done with the input variable //qamp//. If you want a different seasonal variation set //qpha// (default = 102).
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 For lakes with outflow determined by a rating curve, the water level of the lake will be higher than the outflow threshold level. The equilibrium level will depend on the size of the inflow and the outflow rating curve parameters. Depending on the residence time of water in the lake it may take time for this level to be established,​ and until then the outflow of the lake will be simulated lower than it should be. Thus a spin-up time is needed for a model simulation. For lakes with outflow determined by a rating curve, the water level of the lake will be higher than the outflow threshold level. The equilibrium level will depend on the size of the inflow and the outflow rating curve parameters. Depending on the residence time of water in the lake it may take time for this level to be established,​ and until then the outflow of the lake will be simulated lower than it should be. Thus a spin-up time is needed for a model simulation.
 +
 +
 +==== Links to file reference ====
 +
 +^Section ^Symbol ^Parameter/​Data ^File ^
 +|Common lake processes| |//​deeplake//​|[[start:​hype_file_reference:​par.txt|par.txt]]|
 +|Local lake (ilake)| |//gldepi, illdepth//​|[[start:​hype_file_reference:​par.txt|par.txt]]|
 +|:::| |//​icatch//​|[[start:​hype_file_reference:​geodata.txt|GeoData.txt]]|
 +|:::| |//gicatch, illicatch//​|[[start:​hype_file_reference:​par.txt|par.txt]]|
 +|:::| |//gratk, gratp, grata, ilratk, ilratp//​|:::​|
 +|Simple outlet lake or dam (olake)|//​lake<​sub>​depth</​sub>//​|//​lake_depth//​|[[start:​hype_file_reference:​geodata.txt|GeoData.txt]] or [[start:​hype_file_reference:​lakedata.txt|LakeData.txt]] or [[start:​hype_file_reference:​damdata.txt|DamData.txt]]|
 +|:::| |//ratcorr, olratk, olratp//​|[[start:​hype_file_reference:​par.txt|par.txt]]|
 +|:::​|//​wmin//​|calculated from //​regvol//​|[[start:​hype_file_reference:​lakedata.txt|LakeData.txt]] or [[start:​hype_file_reference:​damdata.txt|DamData.txt]]|
 +|:::| |//rate, exp, qamp, qpha//​|[[start:​hype_file_reference:​lakedata.txt|LakeData.txt]] or [[start:​hype_file_reference:​damdata.txt|DamData.txt]]|
 +|:::​|//​qprod//​|//​qprod1,​ qprod2, datum1, datum2//​|[[start:​hype_file_reference:​lakedata.txt|LakeData.txt]] or [[start:​hype_file_reference:​damdata.txt|DamData.txt]]|
 +|Outlet lake with two outlets| |//​ldtype//​=5 or 6|[[start:​hype_file_reference:​lakedata.txt|LakeData.txt]]|
 +|Outlet lake (olake) as a lake basin| |//​ldtype//​=2,​ 3 or 4|[[start:​hype_file_reference:​lakedata.txt|LakeData.txt]]|
 +|:::​|//​lakearea//​|//​area//​|:::​|
  
 ==== Links to relevant modules in the code ==== ==== Links to relevant modules in the code ====
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 Outflow from a subbasin may flow in one or two directions. The main flow follows the main channel, which is the downstream subbasin described by the path given in [[start:​hype_file_reference:​geodata.txt|GeoData.txt]]. If there is a bifurcation,​ the branch flow goes to another downstream subbasin. Any of the flows may go outside the model set-ups area, they are then no longer a concern of the model. There are three ways to determine the flow in the different channels. 1) The division of the total outflow is determined in BranchData.txt. 2) The outflow is calculated for two outlets separately and then divided into the channels. For the second alternative see [[start:​hype_model_description:​hype_routing#​outlet_lake_with_two_outlets|Outlet lake with two outlets]] section above. 3) The demanded flow in the branch is prescibed. If the total flow is not enough to fulfil the need, less water goes into the branch. The main channel gets the rest of the total flow. For the first method the flow division into two channels by BranchData.txt is described by four parameters; //​mainpart//,​ //​maxQ<​sub>​main</​sub>//,​ //​minQ<​sub>​main</​sub>//​ and //​maxQ<​sub>​branch</​sub>//,​ which is set in [[start:​hype_file_reference:​branchdata.txt|BranchData.txt]]. Zero values of the parameters mean they are not used. The main flow (//​mainflow//​) is calculated from the totalflow (//q//) as:  Outflow from a subbasin may flow in one or two directions. The main flow follows the main channel, which is the downstream subbasin described by the path given in [[start:​hype_file_reference:​geodata.txt|GeoData.txt]]. If there is a bifurcation,​ the branch flow goes to another downstream subbasin. Any of the flows may go outside the model set-ups area, they are then no longer a concern of the model. There are three ways to determine the flow in the different channels. 1) The division of the total outflow is determined in BranchData.txt. 2) The outflow is calculated for two outlets separately and then divided into the channels. For the second alternative see [[start:​hype_model_description:​hype_routing#​outlet_lake_with_two_outlets|Outlet lake with two outlets]] section above. 3) The demanded flow in the branch is prescibed. If the total flow is not enough to fulfil the need, less water goes into the branch. The main channel gets the rest of the total flow. For the first method the flow division into two channels by BranchData.txt is described by four parameters; //​mainpart//,​ //​maxQ<​sub>​main</​sub>//,​ //​minQ<​sub>​main</​sub>//​ and //​maxQ<​sub>​branch</​sub>//,​ which is set in [[start:​hype_file_reference:​branchdata.txt|BranchData.txt]]. Zero values of the parameters mean they are not used. The main flow (//​mainflow//​) is calculated from the totalflow (//q//) as: 
  
-<m> mainflow = delim{lbrace}{matrix{4}{2}{q {q<​=minQ_main} {mainpart×(q-minQ_main)+minQ_main} {minQ_main<​q<​=q_thresh} {maxQ_main} {q>​q_thresh \,\ q_thresh={{maxQ_main-minQ_main}/​{mainpart}}+minQ_main} ​ {q-maxQ_branch} ​ {q>​q_thresh\ ,\ q_thresh={{maxQ_branch}/​{1-mainpart}}+minQ_main}}}{} </m>+<m> mainflow = delim{lbrace}{matrix{4}{2}{q {q<​=minQ_main} {mainpart*(q-minQ_main)+minQ_main} {minQ_main<​q<​=q_thresh} {maxQ_main} {q>​q_thresh \,\ q_thresh={{maxQ_main-minQ_main}/​{mainpart}}+minQ_main} ​ {q-maxQ_branch} ​ {q>​q_thresh\ ,\ q_thresh={{maxQ_branch}/​{1-mainpart}}+minQ_main}}}{} </m>
  
  
start/hype_model_description/hype_routing.1533909045.txt.gz · Last modified: 2018/08/10 15:50 by cpers