Q&A: HydroComp Technical Director Don MacPherson

HydroComp, a small engineering firm based in Newmarket, focuses on hydrodynamic and propulsion system simulation, providing design tools for engineers and naval architects to focus on vessel performance, including emissions.

Don MacPherson, HydroComp’s long-tenured technical director, discusses the impacts of tightening emissions regulations, with insights on maximizing new vessel designs and refits.

Q. Maritime has been in the crosshairs of regulators to reduce emissions. What do you see as the top new regulatory issues that are impacting ship and boat design and owners today?

A. We’ve had an opportunity as a solution provider for many years to participate in a number of regulatory working groups for emissions in a broader sense. Both the greenhouse gas emission side, but also in the emerging aspects of underwater radiated noise. And I’ve seen some things that make me question objectives and motivations, not that the people involved are not well intended, certainly they’re intelligent.

Q. What, exactly do you mean?

A. There seems to be a tendency to focus on a methodology; I would use the term orthodoxy in some cases, but that might not be fair in this particular instance. They’re focusing on how to do compliance, rather than trying to achieve broad compliance with simpler methods; for example, the EEXI (Energy Efficiency Existing Ship Index) calculations that are prevalent right now.

Those are a pretty tightly controlled set of calculations through the various class agencies, prescribing a calculation approach using specific types of CFD (computational fluid dynamics) calculation. The people providing the calculations have to show a competency through experience and validation calculations; that is technically valid, I understand the objectives of that. They want to make sure that everything is appropriate and in a comparative way across the board; but it’s unnecessarily complicated.

The lower limit of the bandwidth of companies that are going to have to consider this (are for vessels) as small as 400 gross tons, and that’s not a very big ship. We have one company we work with, a big international bulk carrier company, with four ships that are exactly the same: same hull; same propulsion plants; same missions. They have one set of calculations to do for that particular ship group. But a small company running one ship has to do exactly the same level of effort, and it’s an onerous task.

Q. What’s Hydrocomp’s involvement in underwater noise?

A. We’ve been working with a couple international groups on formally developing compliance regulations for underwater radiated noise. There are people on the regulatory side, people in the biological sciences side, and then there are engineers and naval architects like myself. For whatever reason, this group is hung up on empirical testing as the way to fulfill compliance, as opposed to what I would term rules-based compliance.

I understand how they get there, because noise has always been tested, but interior noise testing for human response is very different than broad propagating radiated noise of a variety of different biological receptors. All the different marine mammals and sea life that are going to be affected by a ship’s radiated noise. It’s not the same thing.

Q. How is HydroComp part of that emission-reduction discussion?

A. Principally through our NavCad software tool, (with users) from small surface vessels, UV companies to the largest merchant shipbuilders, designers, operators. With NavCad you have a variety of different abilities to answer those “what if” questions as a part of this hydrodynamic and propulsion system simulation.

We view everything here at HydroComp as a system problem first, and the system is a vessel propulsor drive system where you have interrelated aspects of performance between the vessel and the propulsor. This could be a propeller or water jet surface drive or cycloidal drive. Then you have relationships up the drive line from the propulsor to the prime mover, which could be a diesel engine, a gasoline engine, electric motor of a variety of different types.

Q. I understand the philosophy of making those critical design decisions early in the process, because as the design and construction progress, it gets exponentially more expensive to change. How common is it for ship owners and builders to embrace that notion?

A. I’m not a big believer in altruism. People do things altruistically to feel good, and a lot of people feel good by investing in the future. My parents were both public school teachers, and they are wired that way. Certain companies are going to be wired that way; doing things because they view it as the right thing to do as opposed to it’s the most profitable thing to do.

Now, to be fair, sometimes the right thing to do also is the profitable thing to do. But when you talk about really looking downstream, that’s very difficult.

The interview is excerpted from the August 2023 edition of Maritime Reporter & Engineering News, and has been edited for length and clarity. Read the full interview at marinelink.com.