diff --git a/src/cpu/NonNewtonianFluids/SimulationObservers/WriteThixotropyQuantitiesSimulationObserver.cpp b/src/cpu/NonNewtonianFluids/SimulationObservers/WriteThixotropyQuantitiesSimulationObserver.cpp
index 4cf31ce321ccb6d28a26840b08e97b15d874e78a..9ea628b2eee1bccdaf407748c223aabfb48d62e1 100644
--- a/src/cpu/NonNewtonianFluids/SimulationObservers/WriteThixotropyQuantitiesSimulationObserver.cpp
+++ b/src/cpu/NonNewtonianFluids/SimulationObservers/WriteThixotropyQuantitiesSimulationObserver.cpp
@@ -47,7 +47,7 @@
 
 using namespace std;
 
-WriteThixotropyQuantitiesSimulationObserver::WriteThixotropyQuantitiesSimulationObserver()
+WriteThixotropyQuantitiesSimulationObserver::WriteThixotropyQuantitiesSimulationObserver() = default;
 {
 
 }