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It is necessary to make modifications to the Friedlander equation approach to make a statement about polynomials as the best equation. Based on the results of the 6" order Table 1. Evaluation of Modification Models of Friedlander (Source: Analysis, 2019)

Table 1 It is necessary to make modifications to the Friedlander equation approach to make a statement about polynomials as the best equation. Based on the results of the 6" order Table 1. Evaluation of Modification Models of Friedlander (Source: Analysis, 2019)

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When P, max 18 the peak of the reflected pressure, tg is the positive phase duration, and b is the coefficient that describes the rate of decay of the pressure-time curve, which is known as the waveform or decay parameter. Following the positive phase comes a period of ‘negative’ pressure (below atmospheric), which is a partial vacuum caused by over-expansion of the shocked air. An idealized pressure-time profile for a reflected blast wave is shown in Figure 1, when P, min 18 the peak under pressure, ty is the negative phase duration, and the positive and negative phase impulses, i, and i,;, are given as the temporal integral of the positive and the negative phase pressure.
When P, max 18 the peak of the reflected pressure, tg is the positive phase duration, and b is the coefficient that describes the rate of decay of the pressure-time curve, which is known as the waveform or decay parameter. Following the positive phase comes a period of ‘negative’ pressure (below atmospheric), which is a partial vacuum caused by over-expansion of the shocked air. An idealized pressure-time profile for a reflected blast wave is shown in Figure 1, when P, min 18 the peak under pressure, ty is the negative phase duration, and the positive and negative phase impulses, i, and i,;, are given as the temporal integral of the positive and the negative phase pressure.
One of the ways to model the blast pressure is to break the linear functions, such as t Krauthammer and Altenberg approach. The positive phase is estimated as a linear form th forms a triangle, with the duration of the linear load, Ty, lin, impulse load adjusted to t empirical method of the triangle load, i.e., Ty, lin = 21; / pr, max. The negative phase modeled as a bilinear approach with an increase in time equal to 1/4 of the duration of t negative phase. Corresponding to the positive phase is the negative linear duration of t phase, tg., tin = 2i;/Pr, min. The negative phase starts at ta, instead of ta, tin, Which giving a ze period of pressure between linear positive and negative phases [2]. The equation is displaye as follows:
One of the ways to model the blast pressure is to break the linear functions, such as t Krauthammer and Altenberg approach. The positive phase is estimated as a linear form th forms a triangle, with the duration of the linear load, Ty, lin, impulse load adjusted to t empirical method of the triangle load, i.e., Ty, lin = 21; / pr, max. The negative phase modeled as a bilinear approach with an increase in time equal to 1/4 of the duration of t negative phase. Corresponding to the positive phase is the negative linear duration of t phase, tg., tin = 2i;/Pr, min. The negative phase starts at ta, instead of ta, tin, Which giving a ze period of pressure between linear positive and negative phases [2]. The equation is displaye as follows:
However, the Friedlander phase with small waveform parameters is a positive triangle phase, which is much easier to evaluate and balance. It is a triangle approach that provides maximum positive moments for the shock phase, with a steep slope to the zero points towards the negative phase, which makes it possible to complete the maximum negative travel to get greater strength quickly. It eliminates waveform parameters and has a more interesting solution. The combination of a hybrid that adjusts to the slope and the impulse balance of the negative phase of Granstrém and the positive phase of the Friedlander triangle is stated as follows:
However, the Friedlander phase with small waveform parameters is a positive triangle phase, which is much easier to evaluate and balance. It is a triangle approach that provides maximum positive moments for the shock phase, with a steep slope to the zero points towards the negative phase, which makes it possible to complete the maximum negative travel to get greater strength quickly. It eliminates waveform parameters and has a more interesting solution. The combination of a hybrid that adjusts to the slope and the impulse balance of the negative phase of Granstrém and the positive phase of the Friedlander triangle is stated as follows:
2.2.5. Extended Friedlander with Teich C Equation Modifications Modeling of the Friedlander’s Blast Wave Equation Using the 6th Order of Polynomial Equations The value in the pressure peak in the Extended Friedlander equation can be more precise if it uses empirical values at certain scale distances. Equations in the positive and negative phases are separated as follows:
2.2.5. Extended Friedlander with Teich C Equation Modifications Modeling of the Friedlander’s Blast Wave Equation Using the 6th Order of Polynomial Equations The value in the pressure peak in the Extended Friedlander equation can be more precise if it uses empirical values at certain scale distances. Equations in the positive and negative phases are separated as follows:
Figure 6. Friedlander Comparison with Extended of Teich C- (Source: Analysis, 2019)
Figure 6. Friedlander Comparison with Extended of Teich C- (Source: Analysis, 2019)
Two pressure functions that consist of polynomials are introduced. The two functions are introduced as different group solutions, which are represented by M. Garces explosion, have a clear burst time, and are balanced against impulses. Reed's Equation 1977 states that the Friedlander explosion equation approach of 1946 is approximated by the 4th order polynomial model, which is stated as follows: [5]
Two pressure functions that consist of polynomials are introduced. The two functions are introduced as different group solutions, which are represented by M. Garces explosion, have a clear burst time, and are balanced against impulses. Reed's Equation 1977 states that the Friedlander explosion equation approach of 1946 is approximated by the 4th order polynomial model, which is stated as follows: [5]
Figure 8. The Modification of Friedlander Equation with Order 6" Polynomial (Source: Analysis, 2019)
Figure 8. The Modification of Friedlander Equation with Order 6" Polynomial (Source: Analysis, 2019)
All the existing equations evaluated based on the category of the ideal equation of the Friedlander 1946, with the following figure 9 and table 1.
All the existing equations evaluated based on the category of the ideal equation of the Friedlander 1946, with the following figure 9 and table 1.
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