An experimental investigation for a looped and parallel-grooved pulsating heat pipe (PHP) was carried out to obtain a steadier start-up process for an electrical apparatus with controlling the input heat flux and condensing temperature. The experimental results show that the working fluid in the pipe abruptly boils in a special condition at the start-up process, and meanwhile the temperature in the evaporating section of PHP falls and the temperature in the condensing section increases. The broad sense thermal resistance of PHP suddenly falls down at the same time. Moreover, the PHP quickly at...
