Access the particle system limit velocity over lifetime module.
using UnityEngine; using System.Collections;
public class ExampleClass : MonoBehaviour { void Start() { ParticleSystem ps = GetComponent<ParticleSystem>(); var lv = ps.limitVelocityOverLifetime; lv.enabled = true; lv.dampen = 0.5f;
AnimationCurve curve = new AnimationCurve(); curve.AddKey( 0.0f, 1.0f ); curve.AddKey( 1.0f, 0.0f ); lv.limit = new ParticleSystem.MinMaxCurve(10.0f, curve); } }