The NISSE payload description
The REXUS 6 rocket campaign is approaching. Currently, the first Hot Countdown is scheduled to be on the 10th March, 2009. Vidar Hølland from the NISSE team has been the main responsible of the mechanical design and construction of the experiment payload together with rocket engineers in the University of Bergen, Norway. The payload is almost ready and some details are described below.
The NISSE experiment is placed in two 356 mm diameter REXUS modules. The water is stored inside a 12 L actuator tank placed in the bottom module. The tank is a clenching vessel split with a bleather filled with nitrogen gas in the bottom half that exerts a pressure on the water in the top half. The maximum operational pressure of the tank is ten bars on the ground. The total pressure is set to eight bars after considering effects of acceleration, rotation, vibration and the removal of the outside air pressure when the release altitude is reached. The total water payload at this pressure will be about 11 liters of non-sparkling mineral water.
The top module contains the release system. The outlet of the tank is split into two. In one end there is a valve for filling the tank with water when the whole system is assembled within the REXUS 6 rocket. This system is mounted 40 mm above the two modules where there will be a hatch through the rocket skin. In the other end, the pipe leads to the main valve. The main valve is operated by two small, electrically triggered, explosives (SQUIBs). From the main valve the water is led into the dividing system with nine pipes directed radially out through the rocket skin. The movement and 3 Hz spin of the rocket will assist the tank pressure in spreading the water at the release region.
A temperature sensor and a pressure sensor are mounted on the release system in order to monitor how temperature and pressure of the water changes during the launch. Total weight of the whole experiment when filled is 30 kg.
