feat(coax,WIP): add options for contraction

src/classes/@ElemPerf/ElemPerf.m

@@ -290,7 +290,7 @@ classdef ElemPerf < handle
         calcforces(self) % Calculate forces, torque and power
         [cl, cd] = getclcd(self, aoaVect, reyVect, i) % Get values of cl and cd
         plotveltriangles(self, nTriangles, varargin)
-        updateupstreamvel(self, PrevOpRot)
+        updateupstreamvel(self, PrevOpRot, Mod)
     end
 
 end

src/configs/caradonna1981.m

@@ -53,6 +53,11 @@ Mod.solvers = {'all'};   % BEMT Solver ('leishman', 'indfact', 'indvel', 'stahlh
 % Extensions/corrections
 Mod.Ext.losses = 'all';  % Include losses using Prandtl formula ('none', 'hub', 'tip', 'both')
 
+% [COAXIAL ONLY] Contraction model
+Mod.coax.model = 'mst'; % Type of contraction ('none', 'sst', 'smst', 'mst')
+Mod.coax.contraType = 'farfield'; % (opt) Type of contraction ('farfield', 'value')
+Mod.coax.contraVal = 1 / 2; % (opt) Contraction ratio between upper disk and lower rotor, [-]
+
 % Numerical parameters
 Mod.Num.convCrit = 1e-4;  % Convergence criterion value,
 Mod.Num.maxIter  = 500;   % Maximum number of iterations for convergence calculations

src/configs/knight1937.m

@@ -48,6 +48,11 @@ Mod.solvers = {'indvel'};   % BEMT Solver ('leishman', 'indfact', 'indvel', 'sta
 % Extensions/corrections
 Mod.Ext.losses = 'all';  % Include losses using Prandtl formula ('none', 'hub', 'tip', 'both')
 
+% [COAXIAL ONLY] Contraction model
+Mod.coax.model = 'mst'; % Type of contraction ('none', 'sst', 'smst', 'mst')
+Mod.coax.contraType = 'farfield'; % (opt) Type of contraction ('farfield', 'value')
+Mod.coax.contraVal = 1 / 2; % (opt) Contraction ratio between upper disk and lower rotor, [-]
+
 % Numerical parameters
 Mod.Num.convCrit = 1e-4;  % Convergence criterion value,
 Mod.Num.maxIter  = 500;   % Maximum number of iterations for convergence calculations

src/configs/template.m

@@ -85,6 +85,11 @@ Mod.solvers = 'all';  % BEMT Solver ('leishman', 'indfact', 'indvel', 'stahlhut'
 % Extensions/corrections
 Mod.Ext.losses = 'none';    % Include losses using Prandtl formula ('none', 'hub', 'tip', 'both')
 
+% [COAXIAL ONLY] Contraction model
+Mod.coax.model = 'mst'; % Type of contraction ('none', 'sst', 'smst', 'mst')
+Mod.coax.contraType = 'farfield'; % Type of contraction ('farfield', 'value')
+Mod.coax.contraVal = 1 / 2; % (opt) Contraction ratio between upper disk and lower rotor, [-]
+
 % Numerical parameters
 Mod.Num.convCrit = 1e-4;  % Convergence criterion value,
 Mod.Num.maxIter  = 500;   % Maximum number of iterations for convergence calculations

src/configs/templatecoax.m

@@ -41,6 +41,7 @@ for i = 2:N_ROTORS
     % ================================ Blade and rotor geometry ====================================
     Blade(i) = Blade(1); % Make second rotor identical to first one
     Blade(i).spinDir = -1 * Blade(i - 1).spinDir; % Invert spin direction for each rotor
+    Blade(i).nElem = round(Blade(i - 1).nElem * 1);
 
     % Shift second rotor w.r.t the application type
     if strcmp(Sim.Misc.appli, 'heli')

src/solvers/bemt.m

@@ -39,7 +39,7 @@ function bemt(OpRot, Mod)
     bemtsinglerot(OpRot(1), Mod);
 
     for i = 2:length(OpRot)
-        OpRot(i).ElPerf.updateupstreamvel(OpRot(i - 1)); % Update upstream velocity
+        OpRot(i).ElPerf.updateupstreamvel(OpRot(i - 1), Mod); % Update upstream velocity
         bemtsinglerot(OpRot(i), Mod); % Calculate BEMT as usual, with new upstream vel distribution
     end
 

src/utils/preproc/validateconfig.m

@@ -74,6 +74,8 @@ function [Sim, Mod, Flow, Op, Airfoil, Blade] = validateconfig(configFile)
     DEF.NONDIM = {'US', 'EU'};
     DEF.VERBOSITY = {'min', 'all'};
     DEF.SOLVERS = {'leishman', 'indfact', 'indvel', 'stahlhut', 'all'};
+    DEF.CONTRACTION_TYPE = {'farfield', 'value'};
+    DEF.CONTRACTION_MODEL = {'none', 'sst', 'smst', 'mst'};
     DEF.FLUID = {'air', 'seawater', 'freshwater'};
     DEF.LOSSES = {'none', 'hub', 'tip', 'both', 'all'};
     DEF.POLARS = {'polynomial', 'file'};
@@ -88,12 +90,12 @@ function [Sim, Mod, Flow, Op, Airfoil, Blade] = validateconfig(configFile)
     % Input checks
 
     Sim = checksim(Sim, configFile, DEF); % Simulation parameters
-    Mod = checkmod(Mod, configFile, DEF); % Models, solvers, etc.
     Flow.fluid = validatestring(Flow.fluid, DEF.FLUID, configFile, 'Flow.fluid'); % Fluid
     Airfoil = checkairfoil(Airfoil, configFile, DEF); % Airfoils data
 
     Blade = checkblade(Blade, configFile, length(Airfoil), DEF); % Blade
     Op = checkop(Op, configFile, DEF, numel(Blade), Flow.fluid); % Operating points
+    Mod = checkmod(Mod, configFile, numel(Blade), DEF); % Models, solvers, etc.
 
     % ===========================================
     % Extra warnings
@@ -169,7 +171,7 @@ end
 % ==================================================================================================
 % ==================================== Models and solvers ==========================================
 % ==================================================================================================
-function Mod = checkmod(Mod, configFile, DEF)
+function Mod = checkmod(Mod, configFile, nRotors, DEF)
 
     % Solvers
     Mod.solvers = cellstr(Mod.solvers);
@@ -195,6 +197,21 @@ function Mod = checkmod(Mod, configFile, DEF)
                        {'scalar', 'positive'}, ...
                        configFile, 'Mod.Num.maxIter');
 
+    if nRotors > 1
+        Mod.coax.model = validatestring(Mod.coax.model, DEF.CONTRACTION_MODEL, ...
+                                        configFile, 'Mod.coax.model');
+        if ~strcmpi(Mod.coax.model, 'none')
+            Mod.coax.contraType = validatestring(Mod.coax.contraType, DEF.CONTRACTION_TYPE, ...
+                                                 configFile, 'Mod.coax.contraType');
+        end
+        if strcmp(Mod.coax.contraType, 'value')
+            validateattributes(Mod.coax.contraVal, ...
+                               {'double'}, ...
+                               {'scalar', 'positive'}, ...
+                               configFile, 'Mod.Num.convCrit');
+        end
+    end
+
 end
 
 % ==================================================================================================