The image represents the infinite acting period.

To compute the infinite acting period, six essential parameters are needed and these parameters are **permeability (k), porosity (φ), well drainage area (A), viscosity (μ), Dimensionless Time to End of Infinite Acting Period ((t _{DA})_{eia}) and total compressibility (C_{T}).**

The formula for calculating the infinite acting period:

t_{eia} = [^{φ μ CT A} / _{0.000263K}] (t_{DA})_{eia}

Where;

t_{eia} = Infinite Acting Period

K = Permeability

φ = Porosity

A = Well Drainage Area

μ = Viscosity

(t_{DA})_{eia} = Dimensionless Time to End of Infinite Acting Period

C_{T} = Total Compressibility

Let’s solve an example;

Given that the permeability is 21, porosity is 15, well drainage area is 32, viscosity is 26, dimensionless time to end of infinite acting period is 44 and total compressibility is 34.

Find the infinite acting period?

This implies that;

K = Permeability = 21

φ = Porosity = 15

A = Well Drainage Area = 32

μ = Viscosity = 26

(t_{DA})_{eia} = Dimensionless Time to End of Infinite Acting Period = 44

C_{T} = Total Compressibility = 34

t_{eia} = [^{φ μ CT A} / _{0.000263K}] (t_{DA})_{eia}

t_{eia} = [^{15 x 26 x 34 x 32} / _{0.000263 x 21}] 44

t_{eia} = [^{424320 }/ _{0.005523}] 44

t_{eia} = [76827810.972] 44

t_{eia} = 3380423682.78

Therefore, the **infinite acting period **is **3380423682.78 s.**

Nickzom Calculator – **The Calculator Encyclopedia** is capable of calculating the infinite acting period.

To get the answer and workings of the infinite acting period using the **Nickzom Calculator – The Calculator Encyclopedia. **First, you need to obtain the app.

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Once, you have obtained the calculator encyclopedia app, proceed to the **Calculator Map, **then click on **Petroleum **under **Engineering**

Now, Click on **Well Testing**** **under **Petroleum**

Now, Click on **Infinite Acting Period**** **under **Well Testing**

The screenshot below displays the page or activity to enter your value, to get the answer for the infinite acting period according to the respective parameter which are the **permeability (k), porosity (φ), well drainage area (A), viscosity (μ), Dimensionless Time to End of Infinite Acting Period ((t _{DA})_{eia}) and total compressibility (C_{T}).**

Now, enter the value appropriately and accordingly for the parameter as required by the **permeability (k)** is **21**,** porosity (φ)** is **15**,** well drainage area (A)** is **32**,** viscosity (μ)** is **26**,** Dimensionless Time to End of Infinite Acting Period ((t _{DA})_{eia})** is

**44**

**and total compressibility (C**is

_{T})**34**.

Finally, Click on Calculate

As you can see from the screenshot above, **Nickzom Calculator**– The Calculator Encyclopedia solves for the infinite acting period and presents the formula, workings and steps too.