diff --git a/advanced-reactor.html b/advanced-reactor.html
index 512f3dd..6594947 100644
--- a/advanced-reactor.html
+++ b/advanced-reactor.html
@@ -8,6 +8,7 @@
             volume: { value: 0., required: true },
             length: { value: 0.},
             resolution_L: { value: 0.},
+            boundary_condition: {value: "Generalised"},
             n_inlets: { value: 1, required: true},
             kla: { value: null },
             S_O_init: { value: 0., required: true },
@@ -75,6 +76,18 @@
                     $(".PFR").show();
                 }
             });
+            $("#node-input-boundary_condition").typedInput({
+                types: [
+                    {
+                        value: "Generalised",
+                        options: [
+                            { value: "Generalised", label: "Generalised"},
+                            { value: "Diriclet", label: "Diriclet"},
+                            { value: "Danckwerts", label: "Danckwerts"}
+                        ]
+                    }
+                ]
+            })
             // Set initial visibility on dialog open
             const initialType = $("#node-input-reactor_type").typedInput("value");
             if (initialType === "CSTR") {
@@ -117,6 +130,10 @@
     <div class="form-row PFR">
         <label for="node-input-resolution_L"><i class="fa fa-tag"></i> Resolution</label>
         <input type="text" id="node-input-resolution_L" placeholder="#">
+    </div>
+        <div class="form-row PFR">
+        <label for="node-input-boundary_condition"><i class="fa fa-tag"></i>Inlet boundary condition</label>
+        <input type="text" id="node-input-boundary_condition">
     </div>
     <div class="form-row">
         <label for="node-input-n_inlets"><i class="fa fa-tag"></i> Number of inlets</label>
diff --git a/src/nodeClass.js b/src/nodeClass.js
index 7919df2..e3c3fd6 100644
--- a/src/nodeClass.js
+++ b/src/nodeClass.js
@@ -70,6 +70,7 @@ class nodeClass {
             volume: parseFloat(uiConfig.volume),
             length: parseFloat(uiConfig.length),
             resolution_L: parseInt(uiConfig.resolution_L),
+            boundary_condition: uiConfig.boundary_condition,
             n_inlets: parseInt(uiConfig.n_inlets),
             kla: parseFloat(uiConfig.kla),
             initialState: [
diff --git a/src/specificClass.js b/src/specificClass.js
index 384aaf0..e670eb5 100644
--- a/src/specificClass.js
+++ b/src/specificClass.js
@@ -10,7 +10,7 @@ const math = create(all, config);
 
 const S_O_INDEX = 0;
 const NUM_SPECIES = 13;
-const DEBUG = false;
+const DEBUG = true;
 
 class Reactor {
     /**
@@ -30,7 +30,7 @@ class Reactor {
 
         this.currentTime = Date.now(); // milliseconds since epoch [ms]
         this.timeStep = 1 / (24*60*15); // time step [d]
-        this.speedUpFactor = 60; // speed up factor for simulation, 60 means 1 minute per simulated second
+        this.speedUpFactor = 1; // speed up factor for simulation, 60 means 1 minute per simulated second
     }
 
     /**
@@ -149,6 +149,8 @@ class Reactor_PFR extends Reactor {
         this.d_x = this.length / this.n_x;
         this.A = this.volume / this.length; // crosssectional area [m2]
 
+        this.BC = config.boundary_condition;
+
         this.state = Array.from(Array(this.n_x), () => config.initialState.slice())
 
         // console.log("Initial State: ")
@@ -178,6 +180,7 @@ class Reactor_PFR extends Reactor {
     set setInfluent(input) {
         super.setInfluent = input;
         if(DEBUG) {
+            console.log("Inlet state max " + math.max(this.state[0]))
             console.log("Pe total " + this.length*math.sum(this.Fs)/(this.D*this.A));
             console.log("Pe local " + this.d_x*math.sum(this.Fs)/(this.D*this.A));
             console.log("Co ad " + math.sum(this.Fs)*this.timeStep/(this.A*this.d_x));
@@ -205,9 +208,23 @@ class Reactor_PFR extends Reactor {
             const BC_gradient = Array(this.n_x).fill(0);
             BC_gradient[0] = -1;
             BC_gradient[1] = 1;
-            let Pe = this.length * math.sum(this.Fs) / (this.D * this.A);
-            let residence_time = this.volume/math.sum(this.Fs);
-            const BC_dispersion = math.multiply((1 - (1 + 4*residence_time/Pe)^0.5) / (Pe*this.d_x), [BC_gradient], state)[0];
+            let BC_term = 0;
+            switch(this.BC) {
+                case "Diriclet":
+                    BC_term = 0;
+                    break;
+                case "Danckwerts":
+                    BC_term = this.D*this.A / math.sum(this.Fs);
+                    break;
+                case "Generalised":
+                    let Pe = this.length * math.sum(this.Fs) / (this.D * this.A);
+                    let residence_time = this.volume/math.sum(this.Fs);
+                    BC_term = (1 - (1 + 4*residence_time/Pe)^0.5) / Pe
+                    break;
+                default:
+                    console.warn("Unknown boundary condition: " + this.BC);
+            }
+            const BC_dispersion = math.multiply(BC_term/this.d_x, [BC_gradient], state)[0];
             state[0] = math.add(BC_C_in, BC_dispersion).map(val => val < 0 ? 0 : val);
         } else { // Neumann BC (no flux)
             state[0] = state[1];