upgrade/v2212-User-Upgrade-Guide.md

@@ -16,6 +16,12 @@ simple error (FatalError), which downgrades to a Warning only when
 loading a functionObject and meant that configuration errors would not
 be noticed.
 
+### Spalart-Allmaras DES models
+
+For `SpalartAllmaras`-based `DES` models, the previously-active `ft2` term is
+deactivated by default. Its activation can now be managed using the new optional
+`ft2` entry which is `false` by default.
+
 
 ## Input Dictionaries
 
@@ -81,6 +87,11 @@ formatOptions
 }
 ```
 
+### Deprecated entries in `histogram`
+
+The `setFormat` and `formatOptions` entries have been silently
+deprecated from the `histogram` function object.
+
 
 ## Changes in utilities
 
@@ -91,6 +102,18 @@ New options `-auto-centre` and `-centre` replace `-auto-origin` and
 aliases). Changing to `-centre` avoids possible confusion in meaning
 with coordinate system `origin()`.
 
+### `effectivenessHeatExchangerSource`
+
+The `effectivenessHeatExchangerSource` fvOption has been renamed to
+`heatExchangerSource`. Its previous behaviour can be recovered by
+using the `heatExchangerSource` with the submodel of `effectivenessTable`.
+
+### `histogram`
+
+The `histogram` function object has been refactored. Its previous behaviour
+can be recovered by using the `histogram` with the submodel of `equalBinWidth`.
+Also, output files per time-step are replaced with a single output file.
+
 
 ----