A numerical code for solving the 1D equations of blood flow in arterial networks
Nektar1D is our in-house code for solving the nonlinear, one-dimensional (1D) equations of blood flow in a given network of compliant vessels subject to boundary and initial conditions. To request all the files needed to compile Nektar1D on your computer, together with examples of 1D model simulations used in our articles, please drop an email to
You can download a reference manual for Nektar1D describing how to compile the code, create and run your own simulations, and interpret the results from here.

For a review on arterial pulse wave haemodynamics and a description of the 1D equations and the numerical scheme used to solve them in Nektar1D, we refer to the following book chapter:

Jordi Alastruey, Kim H. Parker, and Spencer J. Sherwin. Arterial pulse wave haemodynamics. In Anderson S (Ed.), 11th International Conference on Pressure Surges, Virtual PiE Led t/a BHR Group, Chapter 7, 401–442, 2012.

Several tools for analysing the simulated pressure and flow waveforms are described in the following articles:

Marie Willemet and Jordi Alastruey. Arterial pressure and flow wave analysis using time-domain 1D hemodynamics. Ann. Biomed. Eng. 43(1), 190–206, 2014.

PH Charlton, P Celka, B Farukh, P Chowienczyk, and J Alastruey. Assessing mental stress from the photoplethysmogram: a numerical study. Physiological Measurement 39(5), 054001, 2018.

1D modelling provides a good balance between accuracy and computational cost, as we have demonstrated by comparison against (i) experimental data in a 1:1 scale cardiovascular simulator rig of the aorta and its larger branches made of silicone tubes (J Biomech, 2011 & 2007), (ii) in vivo data in humans (J Royal Soc Interface, 2016), and (iii) numerical data obtained by solving the full 3-D equations of blood flow in compliant vessels (Ann Biomed Eng, 2016; Int J Numer Meth Biomed Engng, 2015 & 2014).

We have recently used Nektar1D to create populations of thousands of virtual subjects for in silico evaluation of pulse wave indices and algorithms (J Biomech, 2016; Am J Phys, 2015).