Not having particular experience with that part of Unity just yet, I'll take an educated guess based on my experience with physical simulations in general.

The function documentation states:

function Simulate (deltaTime : float) : void

That is, the function parameter is a time delta, a step in time. It is not a certain moment in time.

Physical simulations work based on discrete steps in time. And the stability of many simulations (or rather the error within a simulation) is directly related to the size of a time step you take.

In your code, you're taking increasingly large steps in time. While single particles might put up with that for a while, given a sufficiently large step they might start to become unstable.

Most likely your problem will be resolved by taking a number of fixed time steps of a relatively small size.

public float initTime;
public ParticleEmitter partEmitter;
// Use this for initialization
public float deltaTime = 0.1f;
void Start () {
    for (float i = 0.0f; i < initTime; i += deltaTime) {
        partEmitter.Simulate(deltaTime);
    }
}

I have taken your 0.1f here (a tenth of a second), but this might have to be even somewhat lower.

The function documentation states:

function Simulate (deltaTime : float) : void

That is, the function parameter is a time delta, a step in time. It is not a certain moment in time.

Physical simulations work based on discrete steps in time. And the stability of many simulations (or rather the error within a simulation) is directly related to the size of a time step you take.

In your code, you're taking increasingly large steps in time. While single particles might put up with that for a while, given a sufficiently large step they might start to become unstable.

Most likely your problem will be resolved by taking a number of fixed time steps of a relatively small size.

public float initTime;
public ParticleEmitter partEmitter;
// Use this for initialization
public float deltaTime = 0.1f;
void Start () {
    for (float i = 0.0f; i < initTime; i += deltaTime) {
        partEmitter.Simulate(deltaTime);
    }
}

I have taken your 0.1f here (a tenth of a second), but this might have to be even somewhat lower.

Not having particular experience with that part of Unity just yet, I'll take an educated guess based on my experience with physical simulations in general.

The function documentation states:

function Simulate (deltaTime : float) : void

That is, the function parameter is a time delta. That is, a step in time. It is not a certain moment in time.

Physical simulations work based on discrete steps in time. And the stability of many simulations (or rather the error within a simulation) is directly related to the size of a time step you take.

In your code, you're taking increasingly large steps in time. While single particles might put up with that for a while, given a sufficiently large step they might start to become unstable.

Most likely your problem will be resolved by taking a number of fixed time steps of a relatively small size.

public float initTime;
public ParticleEmitter partEmitter;
// Use this for initialization
public float deltaTime = 0.1f;
void Start () {
    for (float i = 0.0f; i < initTime; i += deltaTime) {
        partEmitter.Simulate(deltaTime);
    }
}

I have taken your 0.1f here (a tenth of a second), but this might have to be even somewhat lower.

Not having particular experience with that part of Unity just yet, I'll take an educated guess based on my experience with physical simulations in general.

The function documentation states:

function Simulate (deltaTime : float) : void

That is, the function parameter is a time delta, a step in time. It is not a certain moment in time.

Physical simulations work based on discrete steps in time. And the stability of many simulations (or rather the error within a simulation) is directly related to the size of a time step you take.

In your code, you're taking increasingly large steps in time. While single particles might put up with that for a while, given a sufficiently large step they might start to become unstable.

Most likely your problem will be resolved by taking a number of fixed time steps of a relatively small size.

public float initTime;
public ParticleEmitter partEmitter;
// Use this for initialization
public float deltaTime = 0.1f;
void Start () {
    for (float i = 0.0f; i < initTime; i += deltaTime) {
        partEmitter.Simulate(deltaTime);
    }
}

I have taken your 0.1f here (a tenth of a second), but this might have to be even somewhat lower.