Undergrad Relation between change of pressure and temperature in adiabatic process

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In an adiabatic process, the relationship between pressure and temperature is expressed as P.T^(γ/(1-γ)) = Constant, leading to the equation P = Constant.T^(γ/(γ - 1)). The discussion explores the derivation of pressure change (ΔP) in relation to temperature change (ΔT), emphasizing that ΔP is proportional to ΔT raised to a specific power derived from the heat capacity ratio (γ). The equations presented indicate that changes in pressure are directly linked to changes in temperature, reinforcing the fundamental principles of thermodynamics. Overall, the thread seeks validation and further insights on these mathematical relationships.
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I am recently trying to formulate the relation between change in pressure and temperature for adiabatic process. Just submitting the math below for understanding of others. If there is any fault, then kindly rectify me.
In case of adiabatic process, we all know that the relation between temperature and pressure and that's given below:​
P. T(γ/(1-γ)) = Const.
therefore, P = Const. T(γ/(γ - 1))
or, ΔP = Const. (γ/(γ - 1)).ΔT(1/(γ - 1))
It's just an attempt to find out the relation. Don't know how much correct I am. Waiting for comments from others.​
 
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No, it is:
$$P_0T_0^k = C$$
and:
$$PT^k = C$$
Therefore
$$P_0T_0^k = PT^k$$
Where ##k = \frac{\lambda}{1-\lambda}##. Thus:
$$\Delta P = P- P_0$$
$$\Delta P= P_0\left(\left(\frac{T_0}{T}\right)^k-1\right)$$
$$\Delta P = P_0\left(\left(\frac{T}{T_0}\right)^{-k}-1\right)$$
$$\frac{\Delta P}{P_0} = \left(\frac{T_0 + \Delta T}{T_0}\right)^{-k}-1$$
Or:
$$1+ \frac{\Delta P}{P_0} = \left(1+\frac{\Delta T}{T_0}\right)^{\frac{\lambda}{\lambda - 1}}$$
 
There are probably loads of proofs of this online, but I do not want to cheat. Here is my attempt: Convexity says that $$f(\lambda a + (1-\lambda)b) \leq \lambda f(a) + (1-\lambda) f(b)$$ $$f(b + \lambda(a-b)) \leq f(b) + \lambda (f(a) - f(b))$$ We know from the intermediate value theorem that there exists a ##c \in (b,a)## such that $$\frac{f(a) - f(b)}{a-b} = f'(c).$$ Hence $$f(b + \lambda(a-b)) \leq f(b) + \lambda (a - b) f'(c))$$ $$\frac{f(b + \lambda(a-b)) - f(b)}{\lambda(a-b)}...

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