Application of Mass Particle Methods in the Shape Design for Scientific Balloons

This paper proposes a dynamic simulation method for solving balloon shapes. The mass-spring-damping model is used to discretize two-dimensional generatrixes and three-dimensional membrane surfaces, respectively. We solve two-dimensional/three-dimensional ascent shapes at different zero-pressure heights and numerically simulate mushroom cloud shapes that occur during the balloon ground launch. The typical rapid transition feature of the mushroom cloud shape at the waist is depicted. In addition, a preliminary numerical simulation study was conducted for the pumpkin superpressure balloon deployment instability problem. The Calladine instability critical curve for constant angle design lobes is compared and validated for different gore numbers and lobe angles. Further, simulations were carried out on fully inflated shapes of two derived superpressure balloon designs developed by the Japan Aerospace Exploration Agency/Institute of Space and Astronautical Science, namely, the Tawara intermediate cylindrical segment balloon and the diamond-shaped tendon balloon. We verify the ISAS conclusion that the diamond-shaped tendon balloon has a cylindrical shape when fully inflated. Finally, a preliminary simulation study was carried out on the deployment shape of four ballonet architectures in the superpressure balloon. The proposed method for solving various types of balloon shapes based on the mass particle method is simple and efficient, and it has been well applied in our actual balloon engineering.