The control of an elastic fluid

1.2. Quantities which it may be desirable to control. 3 1.The temperature T. 2. The total density, p, or its reciprocal the specific volume.3. The speed q or the component velocities u, v y w. 4. The mass flow per unit area q. 5.The pressure p. 6.The heat content or enthalpy H. 7. The rate of chemical action, evaporation or condensation.8.The coefficient of heat transfer.3 For the control of temperature reference may be made to E. Griffiths, Thermostats and temperature-regulating instruments, Griffin, London,