aeration demand estimate helper

QSD-Group · Feb 6, 2025 · f0c9ed9 · f0c9ed9
1 parent 4c53fd6
commit f0c9ed9
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diff --git a/qsdsan/sanunits/_membrane_bioreactor.py b/qsdsan/sanunits/_membrane_bioreactor.py
@@ -1580,6 +1580,7 @@ def dy_dt(t, QC_ins, QC, dQC_ins):
                 if hasexo: QC = np.append(QC, f_exovars(t))
                 _dstate[:-1] += r(QC)
                 if gstrip: _dstate[gas_idx] -= kLa_stripping * (QC[gas_idx] - S_gas_air)
+                self._cache_OTR = - _dstate[i]
                 _dstate[i] = 0
                 _update_dstate()
         else:        

diff --git a/qsdsan/sanunits/_suspended_growth_bioreactor.py b/qsdsan/sanunits/_suspended_growth_bioreactor.py
@@ -117,6 +117,7 @@ def __init__(self, ID='', ins=None, outs=(), split=None, thermo=None,
         self._concs = None
         self._mixed = WasteStream()
         self.split = split
+        self._cache_OTR = None
 
         # # Design parameters 
         # self._W_tank = W_tank
@@ -370,6 +371,7 @@ def dy_dt(t, QC_ins, QC, dQC_ins):
                 if hasexo: QC = np.append(QC, f_exovars(t))
                 _dstate[:-1] += r(QC)
                 if gstrip: _dstate[gas_idx] -= kLa_stripping * (QC[gas_idx] - S_gas_air)
+                self._cache_OTR = - _dstate[i]
                 _dstate[i] = 0
                 _update_dstate()
         elif isa(aer, Process):
@@ -961,6 +963,7 @@ def __init__(self, ID='', ins=None, outs=(), thermo=None, init_with='WasteStream
         self.gas_stripping = gas_stripping
         self._concs = None
         self._Qs = self.V_tanks * 0
+        self._cache_OTR = None
 
     @property
     def V_tanks(self):
@@ -1227,6 +1230,7 @@ def Rs(Cs):
                 return rxn
 
         if any(DO):
+            _cache_OTR = self._cache_OTR = np.zeros_like(DO)
             aerated_zones = (DO > 0)
             aerated_DO = DO[aerated_zones]
             # @njit
@@ -1246,6 +1250,7 @@ def dy_dt(t, QC_ins, QC, dQC_ins):
                 rxn = Rs(Cs)
                 dy = np.zeros_like(y)
                 dy[:,:-1] = _1_ov_V @ (M_ins - M_outs) + rxn
+                _cache_OTR[aerated_zones] = - dy[aerated_zones, DO_idx]
                 dy[aerated_zones, DO_idx] = 0.
                 if gstrip:
                     S_liq = Cs[:, gas_idx]