Experimental Study on Rocket Nozzle Side Load Reduction

The flow in all rocket engines operated on sea level under ambient conditions will separate inside the supersonic part of the nozzle during transient startup and shutdown. A separated nozzle flow has an asymmetrical distribution in the circumferential direction and therefore induces high side loads. The German Aerospace Center of Lampoldshausen carried out a cold flow subscale test campaign to study devices that can reduce the side loads during transient engine operation. These devices can be installed on either ground test facilities or launch pads. A detailed parametric study was performed, and experimental data demonstrate the potential of the device for side load reduction