To simulate the interaction between the 105mm M111 APFSDS projectile fired from a Merkava I tank and the frontal armor of a T-72A tank, we can use the concept of armor penetration calculations. The penetration of a kinetic energy penetrator like an APFSDS round depends on several factors, including the projectile’s velocity, mass, and shape, as well as the target’s armor composition and angle of impact.

In this scenario, the key components we need are the projectile’s kinetic energy (KE) and the target’s effective armor thickness. The KE of the projectile can be calculated using the formula:

KE = 0.5 * mass * velocity^2

Where:

- Mass of the projectile = ~3.6 kg (including penetrator and cylinders)
- Velocity of the projectile = 1390 m/s

Let’s calculate the KE of the projectile:

KE = 0.5 * 3.6 kg * (1390 m/s)^2 = ~3.04 MJ

Now, let’s calculate the effective armor thickness of the T-72A’s frontal armor. The combination of different layers and angles of armor is somewhat complex, but we can use the concept of effective armor thickness to simplify calculations. The effective armor thickness takes into account the resistance of different armor layers against penetration.

Effective Armor Thickness = (Thickness of RHA layer 1) + (Thickness of glass textolite layers) + (Thickness of RHA layer 2 / cosine(angle))

Where:

- Thickness of RHA layer 1 = 60 mm
- Thickness of glass textolite layers = 2 * 52.5 mm = 105 mm
- Thickness of RHA layer 2 = 50 mm
- Angle of impact = 68 degrees (cosine of 68 degrees is approximately 0.3919)

Effective Armor Thickness = 60 mm + 105 mm + (50 mm / 0.3919) = ~231 mm

Now, we can use the concept of armor penetration to estimate whether the projectile will penetrate the effective armor thickness of the T-72A:

Penetration = (Projectile KE) / (Effective Armor Thickness)

Penetration = 3.04 MJ / 231 mm = ~13.18 MJ/mm

The penetration value of approximately 13.18 MJ/mm is a rough estimate and indicates the kinetic energy available for penetration per unit thickness of armor.

Moreover :

To simulate the interaction between the Merkava I’s 105mm M111 APFSDS projectile and the frontal armor of the T-72A tank, we can use basic armor penetration calculations. The penetration formula is not exact and real-world results may vary due to factors such as projectile quality, armor quality, and other variables. However, this will give you a rough estimate of the outcome.

The penetration capability of an APFSDS round can be estimated using the formula:

Penetration = (Kinetic Energy^2 * Penetrator Constant) / (Target Armor Thickness * Density)

Where:

- Kinetic Energy = 0.5 * Mass * Velocity^2
- Penetrator Constant is a material-specific constant.
- Target Armor Thickness is the total thickness of the armor layers facing the projectile.
- Density is the density of the target armor material.

For Tungsten Alloy, the penetrator constant is around 250,000 (in units of g^0.5 / cm^2).

The density of Tungsten Alloy is about 19.3 g/cm^3.

For Rolled Homogeneous Armor (RHA), the density is about 7.8 g/cm^3.

Let’s plug in the values:

Merkava I Projectile:

- Mass = 3.6 kg
- Velocity = 1390 m/s (at 1.5 km)

T-72A Armor:

- Total Armor Thickness = 60mm + 52.5mm + 52.5mm + 50mm = 215mm
- Density = 7.8 g/cm^3

Calculating kinetic energy:

Kinetic Energy = 0.5 * 3.6 kg * (1390 m/s)^2

Calculating penetration:

Penetration = (Kinetic Energy^2 * Penetrator Constant) / (Target Armor Thickness * Density)

Please note that this calculation doesn’t take into account factors like obliquity (angle of impact) or the potential effects of additional layers such as glass textolite.

Keep in mind that real-world armor penetration is influenced by various factors, including projectile design, target design, armor quality, and obliquity. This estimation provides a simplified approximation and might not accurately represent the complex behavior of armor penetration in combat scenarios. If you’re looking for more accurate results, sophisticated simulation software is often used by defense analysts and engineers to model such interactions.