The Dukler thoery assumes that three fixed factors must be known to establish the value of the average heat-transfer coefficient for condensing inside vertical tubes. These are the terminal Reynolds number, the Prandtl number of the ocndensed phase, and a dimensioless group A_d. The Reynolds number and Pradtl numbers are related to the condensing coefficient in Fig 7-17. However, that figure is based on A_d = 0, which assumes no interfacial shear. A table is provided by Chopey (page 7-50) that provides factors that are function of Reynolds number and A_d.
more on verticle and horizontal tubes
Module for calculation of heat transfer coefficient for condensation in tubes for different orientation