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The general shape of fixed nozzles is pretty close to a solved problem. Per Huzel, even a conical nozzle of sufficient length and 15º half-angle gives better than 95% efficiency. Bell nozzles can exceed 99% efficiency in much shorter form.

The actual engineering design of a nozzle for a large liquid-fueled rocket is more complex; cooling the nozzle becomes a large challenge, and in regeneratively cooled engines, it interacts with the propellant pump system.

In solid rockets, regenerative cooling isn't an option, so I believe ablative cooling is more common, helped by the fact that burn times are often shorter -- typically around 2 minutes instead of 4-6 minutes for liquid first stages. Substantial engineering issues involved in interfacing the casing to vectored nozzles, but again, shape-wise, it's generally a near-optimal bell nozzle.

The general shape of fixed nozzles is pretty close to a solved problem. Per Huzel, even a conical nozzle of sufficient length and 15º half-angle gives better than 95% efficiency. Bell nozzles can exceed 99% efficiency in much shorter form.

The actual engineering design of a nozzle for a large liquid-fueled rocket is more complex; cooling the nozzle becomes a large challenge, and in regeneratively cooled engines, it interacts with the propellant pump system.

In solid rockets, regenerative cooling isn't an option, so I believe ablative cooling is more common, helped by the fact that burn times are often shorter -- typically around 2 minutes instead of 4-6 minutes for liquid first stages. Substantial engineering issues involved in interfacing the casing to vectored nozzles, but again, shape-wise, it's generally a near-optimal bell nozzle.

Either the Huzel or Sutton book will take you through the next couple of levels of complexity on the topic.

The general shape of fixed nozzles is pretty close to a solved problem. Per Huzel, even a conical nozzle of sufficient length and 15º half-angle gives better than 95% efficiency. Bell nozzles can exceed 99% efficiency.

The actual engineering design of a nozzle for a large rocket is more complex; cooling the nozzle becomes a large challenge, and in regeneratively cooled engines, it interacts with the propellant pump system.

The general shape of fixed nozzles is pretty close to a solved problem. Per Huzel, even a conical nozzle of sufficient length and 15º half-angle gives better than 95% efficiency. Bell nozzles can exceed 99% efficiency in much shorter form.

The actual engineering design of a nozzle for a large liquid-fueled rocket is more complex; cooling the nozzle becomes a large challenge, and in regeneratively cooled engines, it interacts with the propellant pump system.

In solid rockets, regenerative cooling isn't an option, so I believe ablative cooling is more common, helped by the fact that burn times are often shorter -- typically around 2 minutes instead of 4-6 minutes for liquid first stages. Substantial engineering issues involved in interfacing the casing to vectored nozzles, but again, shape-wise, it's generally a near-optimal bell nozzle.

The general shape of fixed nozzles is pretty close to a solved problem. Per Huzel, even a conical nozzle of sufficient length and 15º half-angle gives better than 95% efficiency. Bell nozzles can exceed 99% efficiency.

The actual engineering design of a nozzle for a large rocket is more complex; cooling the nozzle becomes a large challenge, and in regeneratively cooled engines, it interacts with the propellant pump system.

The general shape of fixed nozzles is pretty close to a solved problem. Per Huzel, even a conical nozzle of sufficient length and 15º half-angle gives better than 95% efficiency. Bell nozzles can exceed 99% efficiency.

The actual engineering design of a nozzle for a large rocket is more complex; cooling the nozzle becomes a large challenge, and in regeneratively cooled engines, it interacts with the propellant pump system.