Han Shik Chung
The Journal of Mechanical Science and Technology, vol. 22, no. 5, pp.981-990, 2008

Abstract : Air-heating vaporizers are usually used to regasify LNG at satellite areas because of the small demand for natural gas there. The common type of air heating vaporizer which exists in the market is the longitudinally finned type with 8 fins, 50mm fin length and 2mm fin thickness. To contribute in developing an efficient air-heating vaporizer, experiment on finned type air-heating vaporizer using 8 fins, 50mm fin length with 2mm fin thickness (8fin50le) -which exist in the market- and 4 fins, 75mm fin length with 2mm fin thickness (4fin75le), which is proposed, were conducted. Then, both types of vaporizers are compared. The experiments were conducted in one hour by varying the ambient condition and the length of the vaporizer. The ambient air was controlled so that it has the same condition (same temperature, humidity and air velocity) with air condition in every season available and the length was varied 4000mm, 6000mm and 8000mm for each type of vaporizer. Additional experiment with longer duration, i.e., 4 hours and in a single room condition was conducted to validate the previous result. In this experiment, the main aspects in analyzing the characteristics of the air heating vaporizer are the inlet-outlet enthalpy difference and the outlet temperature of the working fluid. LN2 is used to substitute LNG for safety reasons. The results show that the characteristics of the finned type 4fin75le vaporizer are comparable to the finned type 8fin50le vaporizer.

Keyword : LNG (Liquefied Natural Gas); LN2 (Liquid Nitrogen); Vaporizer; Fin; Super low temperature