Steam heated calorifier - having elements with change from circular to rectangular to improve heat transfer from condensate

摘要

Calorifier for steam heating hot water for space heating purpose has elements enclosed in a vessel or container. The elements consist of a spiral of circular pipe which change into rectangular suction further down. This is so as to improve the ratio of surface area to cross section in the lower portion because here the steam has fully condensed and is condensate of lower volume and poorer hot-transfer coefficient. The diameter of the rectangular spiral is smaller than that of the circular spiral. The lower portion can also have elliptical cross section.