I am interested to know the significance of the energy conservation laws when modelling fluids (or other materials). Am I correct in saying that if energy is conserved then stability is achieved. In a way, I need to know why it is important to show that energy is conserved when modelling different phenomena (which can be described by using mass and momentum equation, without the need for the energy equation)If you know any reading materials please let me know. 
significance of energy equation and its conservation
fluid dynamics;stability;conservation