液体燃料火箭发动机性能可靠性的统计评定

 一批液体燃料火箭发动机的性能指标X是。N（μ,σ）,σ²=σ_A²+σ_E²,σ_A²是发动机性能的台间方差,σ_E²是台内方差。设计要求是“μ∈μ_L,μ_U]、σ≤B”。本文提供了根据发动机的试验数据,能否以置信度γ,判定批产品性能满足设计要求的方法。

STATISTICAL ESTIMATION OF LIQUID PROPELLANT ROCKET ENGINE PARAMETERS

Let the liquid propellant rocket engine parameter X be the Normal probability distribution of μ and σ2, σ2 = σA2 + σE2, where σE2 is the engine run to run variance and σA2 is the engine to engine variance. The design criteria of the rocket engine are: "μ∈μL,μU]" and "σ≤B", where μL and μU are kNown as the lower and the upper bounds of μ. B2 is the upper bound of σ2. The Inter-agency Chemical Rocket Propulsion Group of U. S. A. had given the formula of μ （the point estimate of μ） and the formula of σ （σ2 is the point estimate of σ2） from experimental values. But μ∈μL, μU] and σ≤B are Not equivalent to μ∈μL,μU] and σ≤B. This paper considers the problem of setting confidence intervals to the μ and σ for assigned confidence coefficient γ. μ lies in the interval , where σ2 lies in the interval ] ,where