Since the porosity affects not only the density but also the properties of the composites, porosity reduction is a critical issue in both ceramic matrix and carbon matrix composites. Please list at least two methods to decrease/or control the porosity in ceramic matrix and carbon matrix composites respectively

Estimate the change in specific internal energy au and specific enthalpy h from inlet to outlet for ethylene glycol (a liquid) flowing through each of the following devices: (a) a heat exchanger where the glycol temperature increases from 20 °c to 80 °c; (b) a pump operating at about 25 °c and increasing the glycol pressure from 100 kpa to 8 mpa.