TABLE 1. CALCULATIONS USED TO DETERMINE THE WETTED SURFACE AREA OF ASME 2:1 SE HEADS OF PARTIALLY FILLED HORIZONTAL VESSELS Where p = ln(3)/ln(2). An ellipsoid's partial surface area is not defined but can be calculated by numeric analysis as the sum of finite segments of frustums along any axis. Table 1 shows the equations used for this calculation. A frustum between each elliptical xy-plane of any shaped ellipsoid (for example, an egg) along its z-axis is calculated using the following Equation 3: Wetted surface area (analytic approximation method) of both heads: (1) Calculating wetted surface area (rigorous numeric analysis) (2) (3) (4) Volume at liquid level = h (analytic approximation) of both heads (5) A 2:1 SE head is an oblate spheroid (Figure 1), of which c = a and b = a/2. The calculation of each frustrum from ai+1 to ai then reduces to: Volume at liquid level = h (rigorous numeric analysis) (6) (7) (8) Per the Pythagorean theorem, the semi-major axis (a) of each successive xy plane is Wetted surface area and volume of the cylindrical section of the horizontal vessel (9) (10) Proven Vacuum Technology for Chemical Processes › Custom solutions to meet your requirements › Safe pumping of hazardous flammable material › Know-how from project conception to completion › Worldwide service support 1-800-USA-PUMP I info@buschusa.com www.buschusa.com For details visit adlinks.chemengonline.com/70311-05 CHEMICAL ENGINEERING WWW.CHEMENGONLINE.COM OCTOBER 2018 59http://www.buschusa.com http://adlinks.chemengonline.com/70311-05 http://WWW.CHEMENGONLINE.COM