diff --git a/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/flow_and_temperature_control/PowerCurveConstantFlow/c_PowerCurveConstantFlow.md b/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/flow_and_temperature_control/PowerCurveConstantFlow/c_PowerCurveConstantFlow.md
new file mode 100644
index 0000000000000000000000000000000000000000..0461b54b8cc09fddb0ec5a42829bb54adf0127d0
--- /dev/null
+++ b/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/flow_and_temperature_control/PowerCurveConstantFlow/c_PowerCurveConstantFlow.md
@@ -0,0 +1 @@
+It represents the heat load on the BHE is various with time, but the flow rate of circulating fluid is constant.
diff --git a/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/flow_and_temperature_control/PowerCurveConstantFlow/t_flow_rate.md b/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/flow_and_temperature_control/PowerCurveConstantFlow/t_flow_rate.md
new file mode 100644
index 0000000000000000000000000000000000000000..c82def9f5d6fa47ea06dfd6a35643906b0f2659b
--- /dev/null
+++ b/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/flow_and_temperature_control/PowerCurveConstantFlow/t_flow_rate.md
@@ -0,0 +1 @@
+It is the flow rate of circulating fluid.
diff --git a/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/flow_and_temperature_control/PowerCurveConstantFlow/t_power_curve.md b/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/flow_and_temperature_control/PowerCurveConstantFlow/t_power_curve.md
new file mode 100644
index 0000000000000000000000000000000000000000..9775bf49f45c28671ee5b8aef39cf4f94a8d4588
--- /dev/null
+++ b/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/flow_and_temperature_control/PowerCurveConstantFlow/t_power_curve.md
@@ -0,0 +1 @@
+The curve stands for the variation of heat load on the BHE.
diff --git a/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/pipes/t_inner.md b/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/pipes/t_inner.md
new file mode 100644
index 0000000000000000000000000000000000000000..2126bdbc2ed24a59b5c61c1cb554d627976305ea
--- /dev/null
+++ b/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/pipes/t_inner.md
@@ -0,0 +1 @@
+It is the inner pipe in coaxial pipe system, such as CXA and CXC.
diff --git a/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/pipes/t_outer.md b/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/pipes/t_outer.md
new file mode 100644
index 0000000000000000000000000000000000000000..ae9aefe1f0b79d8118890a5e3548aa428b15ced9
--- /dev/null
+++ b/Documentation/ProjectFile/prj/processes/process/HEAT_TRANSPORT_BHE/borehole_heat_exchangers/borehole_heat_exchanger/pipes/t_outer.md
@@ -0,0 +1 @@
+It is the outer pipe in the coaxial pipe system.