honeybee_plus.radiance.sky.gendaylit module

Calculate sky values based on Radiance’s gendaylit.

This code is parts of genddaylit.c whic is copyrighted by:

Copyright (c) 1994,2006 *Fraunhofer Institut for Solar Energy Systems

Heidenhofstr. 2, D-79110 Freiburg, Germany Agence de l’Environnement et de la Maitrise de l’Energie Centre de Valbonne, 500 route des Lucioles, 06565 Sophia Antipolis Cedex, France *BOUYGUES 1 Avenue Eugene Freyssinet, Saint-Quentin-Yvelines, France

You can check the source code at:

https://github.com/NREL/Radiance/blob/53485a7fb48727293d62f98d7bac830aa34ccba4/src/

gen/gendaylit.c

honeybee_plus.radiance.sky.gendaylit.air_mass(sunzenith)

Enter sunzenith angle (degrees) return relative air mass (double).

honeybee_plus.radiance.sky.gendaylit.calc_rel_lum_perez(dzeta, gamma, z, epsilon, delta, coeff_perez)

Sky luminance perez model.

honeybee_plus.radiance.sky.gendaylit.check_input_values(directilluminance, diffuseilluminance, altitude)

Validity of the direct and diffuse components.

honeybee_plus.radiance.sky.gendaylit.check_parametrization(skyclearness, skybrightness)

Check the range of epsilon and delta indexes of the perez parametrization.

honeybee_plus.radiance.sky.gendaylit.coeff_lum_perez(z, epsilon, delta, coeff_perez)

Coefficients for the sky luminance perez model.

honeybee_plus.radiance.sky.gendaylit.direct_n_effi_perez(skyclearness, skybrightness, sunzenith)

Direct normal efficacy model, according to PEREZ.

honeybee_plus.radiance.sky.gendaylit.gendaylit(altitude, month, day, hour, directirradiance, diffuseirradiance, output_type=0)

Get solar irradiance.

Parameters

• altitude – Sun altitude in degrees.

• month – A value for month between 1-12.

• day – A value for day between 1-31.

• hour – A value for hour between 0-23.

• directirradiance – Direct irradiance value.

• diffuseirradiance – Diffuse irradiance value.

• output_type – An integer between 0-2. 0=output in W/m^2/sr visible, 1=output in W/m^2/sr solar, 2=output in candela/m^2 (default: 0).

Returns

solar irradiance.

Return type

solarradiance

honeybee_plus.radiance.sky.gendaylit.get_eccentricity(day_angle)

Enter day number, return E0 = square(R0/R): eccentricity correction factor.

honeybee_plus.radiance.sky.gendaylit.get_numlin(epsilon)

honeybee_plus.radiance.sky.gendaylit.glob_h_diffuse_effi_perez(skyclearness, skybrightness, sunzenith)

Global horizontal diffuse efficacy model, according to PEREZ.

honeybee_plus.radiance.sky.gendaylit.integ_lv(lv, theta)

honeybee_plus.radiance.sky.gendaylit.radians(degres)

honeybee_plus.radiance.sky.gendaylit.sky_brightness(diffuseirradiance, sunzenith, day_angle)

honeybee_plus.radiance.sky.gendaylit.sky_clearness(diffuseirradiance, directirradiance, sunzenith)

Perez sky’s clearness.

honeybee_plus.radiance.sky.gendaylit.theta_phi_to_dzeta_gamma(theta, phi, z)

Calculation of the angles dzeta and gamma.