Gas Leak (Effusion): Solving Differential Equation

In summary, the conversation is about solving a differential equation for a gas leaking out of a container through a small pinhole. The solution yields an exponential function with a constant as the exponent, which should be dimensionless for the equation to make sense. The experts suggest a more precise formula to use.
  • #1
moonman
21
0
I'm working on a question where gas is leaking out of a container from a small pinhole. I have a differential equation dN/dt = (Constants)*N. I solved this to get an exponential. The exponent is that group of constants, which are A/2V*(kT/m)^1/2. Shouldn't the exponent have something to do with time? Because if they don't, the dimensions don't work out. Can anyone clear this up for me?
 
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  • #2
dN/dt = C * N
yields
N = N0 * exp (C * t)
,where t is time

BTW, this is not "Advanced Physics" ;-)
 
  • #3
You're right, that's not advanced physics, its simple DE. But that's not what I asked.
For that equation to make sense, the exponent should be dimensionless. C*t is not. That's the part I don't understand
 
  • #4
N is a count ... dN/dt has units counts/sec ... C must have units 1/sec.
 
  • #5
If A is area and V is volume (and yes, they are) then dimension of your constant is
m2/m3 * m/s = 1/s
and no problem.
I advise to use more precise formula
dN/dt = -1/4 n*<v>*A = -1/4 AN/V * sqrt[kT/(2*3.1416*m)]
 

FAQ: Gas Leak (Effusion): Solving Differential Equation

1. What is a gas leak and how does it occur?

A gas leak is the unintentional release of gas from a containment system, such as a pipeline or storage tank. It can occur due to factors such as corrosion, equipment failure, or human error.

2. How does effusion play a role in gas leaks?

Effusion is the process of gas molecules escaping through a small opening. In the case of a gas leak, effusion occurs when the gas escapes through a crack or hole in the containment system, leading to the release of the gas into the surrounding environment.

3. What is a differential equation and how is it used to solve gas leak problems?

A differential equation is a mathematical equation that describes the relationship between a function and its derivatives. In the context of gas leaks, a differential equation can be used to model the rate of effusion and predict the behavior of the gas leak over time.

4. What factors influence the solution of a differential equation for a gas leak?

The solution of a differential equation for a gas leak can be influenced by various factors, such as the type of gas, the size of the opening, the temperature and pressure of the gas, and the surrounding environmental conditions.

5. How can solving a differential equation help prevent or mitigate gas leaks?

By solving a differential equation for a gas leak, scientists and engineers can gain a better understanding of the behavior of the gas leak and make more accurate predictions about its potential impact. This information can then be used to develop strategies for preventing or mitigating future gas leaks.

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