Preheating air effect (Equations)

Objective: `Q_("total")=Q_("work")+Q_("loss")` `sumQ=M_("air")*H_("air")+M_("air")*H_("air")+M_("products")*H_("products")-Q_("work"+"loss")=0` `M_("air")*H_("air")+M_("fuel")*H_("fuel")+(M_("air")+M_("fuel"))*H_("products")=Q_("work"+"loss")` `M_("air")/M_("fuel")*H_("air")+M_("fuel")/M_("fuel")*H_("fuel")+(M_("air")/M_("fuel")+M_("fuel")/M_("fuel"))*H_("products")=Q_("work"+"loss")/M_("fuel")`…