Accumulator Capacity – Usable Volume Per Bottle

To find Accumulator Capacity usable volume per bottle we will use Boyle’s Law for ideal gases, which I have listed below:

Boyle’s Law = P1 V1 = P2 V2

With that being said, there are 3 steps that must be utilized in order to complete this calculation. These steps are listed below along with some general guidelines for calculation purposes:

In general, and when addressing Accumulator Capacity usable volume per bottle, we can consider the following data as usable guidelines:

- Volume per bottle = 10 gallons

- Precharge pressure = 1000 psi

- Max pressure = 3000 psi

- Min pressure remaining post activation = 1200 psi

- Pressure gradient of hydraulic fluid = 0.445 psi/ft

NOTE – However, the above are ONLY guidelines and can change!

- Step 1 is to determine the necessary amount of hydraulic fluid necessary to increase pressure from a precharge to a MINIMUM.

Boyle’s Law = P1 V1 = P2 V2

So,

a. 1000 psi x 10 gal = 1200 psi x V2

b. 10,000 / 1200 = V2

c. V2 = 8.33 (nitrogen is compressed from 10.0 gal to 8.33 gal)

d. Then, 10.0 — 8.33 = 1.67 gallons of hydraulic fluid per bottle.

- Step 2 is to determine the necessary amount of hydraulic fluid necessary to increase pressure from a precharge to a

MAXIMUM.

Boyle’s Law = P1 V1 = P2 V2

So,

a. 1000 psi x 10 gals = 3000 psi x V2

b. 10,000 / 3000 = V2

c. V2 = 3.33 (nitrogen is compressed from 10 gal to 3.33 gal)

d. Then, 10.0 — 3.33 = 6.67 gallons of hydraulic fluid per bottle.

-Step 3 is to find the usable volume per bottle, which can be done by using the following formula:

Useable volume per bottle = Total hydraulic fluid per bottle — unused hydraulic fluid per bottle

So,

Useable volume per bottle = 6.67 — 1.67

Useable volume per bottle = 5 gallons